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<H2>January 2001, Issue 61 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
Published by <I>Linux Journal</I></H2>
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<H1><font color="#BB0000">Table of Contents:</font></H1>
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<LI> <a HREF="lg_mail61.html">The MailBag</A>
<LI> <a HREF="lg_bytes61.html">News Bytes</A>
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<LI> <a HREF="lg_bytes61.html#distro">Distro News</A>
<LI> <a HREF="lg_bytes61.html#general">News in General</A>
<LI> <a HREF="lg_bytes61.html#software">Software Announcements</A>
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<LI> <a HREF="lg_answer61.html">The Answer Gang</A> , <EM>by The <EM>Linux Gazette</EM> Answer Gang</EM>
<LI> <a HREF="lg_tips61.html">More 2-Cent Tips</A>
<LI> <a HREF="andreiana.html">Linux On Your Desktop: Setting Up GNOME</A> , <EM>by Marius Andreiana</EM>
<LI> <a HREF="collinge.html">HelpDex</A> , <EM>by Shane Collinge</EM>
<LI> <a HREF="dellomodarme.html">Using ssh</A> , <EM>by Matteo Dell'Omodarme</EM>
<LI> <a HREF="evans.html">The emelfm File Manager</A> , <EM>by Paul Evans</EM>
<LI> <a HREF="kasten.html">Tuxedo Tails</A> , <EM>by Eric Kasten</EM>
<LI> <a HREF="nielsen.html">Using the Wireless Modem Ricochet</A> , <EM>by Mark Nielsen</EM>
<LI> <a HREF="nielsen2.html">When Apache Redirect Doesn't Work the First Time</A> , <EM>by Mark Nielsen</EM>
<LI> <a HREF="okopnik.html">Learning Perl, part 1</A> , <EM>by Ben Okopnik</EM>
<LI> <a HREF="padala.html">Booting Linux from the NT Boot Menu</A> , <EM>by Pradeep Padala</EM>
<LI> <a HREF="steffler.html">Making Smalltalk: Bags o' Fun</A> , <EM>by Jason Steffler</EM>
<LI> <a HREF="ward.html">Setting Up a Linux Laptop With No CD-ROM Drive</A> , <EM>by Alan Ward</EM>
<LI> <a HREF="lg_backpage61.html">The Back Page</A>
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<LI> <a HREF="lg_backpage61.html#authors">About This Month's Authors</A>
<LI> <a HREF="lg_backpage61.html#notlinux">Not Linux</A>
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<H3 ALIGN="center"><EM>Linux Gazette</EM> Staff and The Answer Gang</H3>
<BLOCKQUOTE>
<STRONG>Editor:</STRONG> Michael Orr<BR>
<STRONG>Technical Editor:</STRONG> Heather Stern<BR>
<STRONG>Senior Contributing Editor:</STRONG> Jim Dennis<BR>
<STRONG>Contributing Editors:</STRONG>
Michael "Alex" Williams, Don Marti, Ben Okopnik
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<I>Linux Gazette</I><img alt="[tm]" src="../gx/tm.gif">,
<A HREF="http://www.linuxgazette.com/">http://www.linuxgazette.com/</A><BR>
This page maintained by the Editor of <I>Linux Gazette</I>,
<A HREF="mailto: gazette@ssc.com"> gazette@ssc.com</A>
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<H5>Copyright &copy; 1996-2001 Specialized Systems Consultants, Inc.</H5>
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<H2><a NAME="mail"><IMG SRC="../gx/mailbox.gif" ALIGN=MIDDLE ALT=" ">
The Mailbag!</a> </H2>
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<H3>Contents:</H3>
<ul>
<li><a HREF="#help">Help Wanted -- Article Ideas</a>
<li><a HREF="#gen">General Mail</a>
<li><a HREF="#gaz">Gazette Matters</a>
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Write the <i>Linux Gazette</i> at
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questions to the Answer Gang at
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<center><H3><font color="maroon">Help Wanted -- Article Ideas</font></H3></center>
<P>These questions have been selected among the hundreds the <I>Gazette</I>
recieves each month. Article submissions on these topics will be eagerly
accepted at <a href="mailto:gazette@ssc.com">gazette@ssc.com</a>, and posted
in the next issue.
<P>
Answers to these questions should be sent directly to the e-mail address of
the inquirer with or without a copy to gazette@ssc.com. Answers that are
copied to <I>LG</I> will be printed in the next issue -- in the Tips column
if simple, the Answer Gang if more complex and detailed.
<P> <STRONG>Before asking a question, please check the
<A HREF=../faq/index.html><I>Linux Gazette</I> FAQ</A> to see if it has been
answered there. The AnswerGuy
"<a href="../tag/kb.html">past answers index</a>" may also be helpful
(if a bit dusty).
</STRONG>
<P> <HR> <P>
<!--====================================================================-->
<UL>
<!-- index_text begins -->
<li><A HREF="#wanted/1"
><strong>Internet Cafe Management Software</strong></a>
<li><A HREF="#wanted/4"
><strong>geforce card</strong></a>
<li><A HREF="#wanted/5"
><strong>Hiding samba shares across multiple networks</strong></a>
<!-- index_text ends -->
</UL>
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="wanted/1"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">Internet Cafe Management Software</FONT></H3>
Wed, 27 Dec 2000 08:39:31 -0600 (CST)
<BR>From: Alan Pater &lt;<A HREF="mailto:linux-questions-only@ssc.com?cc:alan@celasmaya.edu.gt"
>alan@celasmaya.edu.gt</A>&gt;
<P>
Hi Folks.
</P>
<P>
I've taken a quick look around the web for Linux based Internet
Cafe Software, with no luck. There's a few windows based packages
around, but that will just not do. What I'm looking for is
something which can record when people login and logoff and
calculate how much they should pay. Have you seen anything like
that? Even a set of instructions on how to do it with a set of
scripts would be cool.
</P>
<P>
Alan Pater
</P>
<P>
www.celasmaya.edu.gt
</P>
<p>Can any of our fair readers find some good internet cafe or "walk in ISP"
software? We can only offer the following leads: </p>
<em>
<p>Try looking around including the keyword Coffeenet. That was a Linux
based cafe in the S.F. area; he closed shop when he had his lease end,
but it was successful before that, the building owner just didn't want
to renew. I'm pretty sure he open sourced the distro he created, but
note, it depends on having a serious NFS server in the back.
</P>
<P>
I know the <A HREF="http://www.valinux.com/">VA Linux</A> "mail garden" machines and his, had a similar feature
of cleaning up after anything local, so the machines never have any
interesting leftovers from previous clients. xdm or gdm have control
files for stuff to do before and after a session, so it should be possible
to add accounting functions to logging in and out, and to add cleanup
to logging out, quite easily. Keeping people from accessing text mode
is a little more work, but I don't think Coffeenet was preventing that.
</P>
<P>
Neither of these actually kick someone out when their time is up, so you
still have some work to do if your shop is too big to merely keep an eye
on people and rely on a popup "you've been on for awhile" note.
<br>-- Heather
</P>
</em>
<P>
I don't know of any scripts, but "last" gives you login/logout times
by user. Should be possible to dump the output into a database
via some pretty simple awk, perl, python, or even sh scripts.
</P>
<P>
Last reads wtmp, so watch out for when your wtmp gets rotated.
Most log rotation scripts will move wtmp to a backup, for example
wtmp.1, and "last" will take a filename as a parameter.
</P>
<P>
Sample output from "last":
</P>
<P><BLOCKQuote><PRE>
[ ... ]
dlong ttyp3 passenger.ssc.co Fri Dec 1 09:21 <TT>-</TT> 09:22 (00:00)
carrie ttyp5 catnip.ssc.com Fri Dec 1 08:48 <TT>-</TT> 17:04 (08:15)
fax_inc ttyS0 +39 45 877 Fri Dec 1 08:43 <TT>-</TT> 08:44 (00:01)
annie ttyp4 passenger.ssc.co Fri Dec 1 08:42 <TT>-</TT> 14:48 (06:06)
dlong ttyp3 passenger.ssc.co Fri Dec 1 08:20 <TT>-</TT> 09:03 (00:42)
[ ... ]
</PRE></BLOCKQuote></P>
<P>
See "man last".
<br>-- Dan Wilder
</P>
<!-- end 3 -->
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<P> <A NAME="wanted/4"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">geforce card</FONT></H3>
Mon, 25 Dec 2000 12:27:50 +1100
<BR>From: "Ron Nicholls" &lt;<A HREF="mailto:linux-questions-only@ssc.com?cc:nykysle@bigpond.com"
>nykysle@bigpond.com</A>&gt;
<P>
I have RH 7.0 which has XFree86 4.0.1 which does not
support Geforce 2 chips yet.
Is there a patch or update or howto to install the necessary
support.
</P>
<P>
Regards
RonN
</P>
<em><p>Any developer types want to help him out here? Xfree86 4.0.2
came out, but it still has no special support for this card, so unless
it works in VESA mode, he's out of luck for now...</p>
<p>And, we'll galdly take articles on adding support for new cards to X
version 4! -- Heather</p>
</em>
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="wanted/5"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">Hiding samba shares across multiple networks</FONT></H3>
Fri, 15 Dec 2000 10:07:36 -0800 (PST)
<BR>From: Faber Fedor &lt;<A HREF="mailto:linux-questions-only@ssc.com?cc:faberfedor@yahoo.com"
>faberfedor@yahoo.com</A>&gt;
<P>
Hi guys (and Heather
<IMG SRC="../gx/dennis/smily.gif" ALT=":-)"
height="24" width="20" align="middle">!
</P>
<P>
I've got an interesting little problem with Samba and hiding shares when
multiple networks are involved. I'm hoping one of you can help out, or maybe
one of the Gentle Readers has already done this.
</P>
<P>
I have one Samba box with two network interfaces (on one NIC using virtual
lans), say 192.168.1.10 and 192.168.2.10. Two companies sit on each network and
can't learn about the other. Let's call them "Acme, Limited" (192.168.1.0/24)
and "Coyotes-R-Us" (192.168.2.0/24). They, of course, use Another Operating
System.
</P>
<P>
What I want to do is to create shares on the Samba box for Acme and Coyote to
store their files. That's easy enough, the problem is in restricting what they
see.
</P>
<P>
If I create Acme and Coyote as users and share the home directories via the
[homes] default share, Acme will not see Coyote's share and vice versa. This
is good. However, if the CEO of "Coyotes-R-Us", Mr. Wiley, logs onto the Acme
network, he will see the Coyote [home] share appear on the Acme network. This
is NOT a Good Thing.
</P>
<P>
(I tested this by placing a Windows box on Acme's network via a port on a Cisco
switch that was set up to handle only Acme's vlan.)
</P>
<P>
If, OTOH, I set them up as separate shares and restrict them via IP addresses a
la "allowed_hosts=", both companies can see the other's share, which is Not A
Good Thing, even though they cannot access the other's share (always a good
thing).
</P>
<P>
I've been hacking at this for several days trying to figure something out, as
well as surfing Google, Deja.com, the samba mailing lists, and any other place
I could think of. You are my Last Great Hope.
<IMG SRC="../gx/dennis/smily.gif" ALT=":-)"
height="24" width="20" align="middle">
</P>
<P>
TIA!
</P>
<P>
=====
Sincerely,
Faber Fedor
</P>
<em><p>It looks like the Answer Gang could stand to be joined by a serious
Samba expert. Anyone care to jump in?</p></em>
<!-- end 5 -->
<P> <hr> <P>
<!-- =================================================================== -->
<a name="gen"></a>
<center><H3><font color="maroon">General Mail</font></H3></center>
<P> <HR> <P>
<!--====================================================================-->
<!-- BEGIN general mail -->
<UL>
<!-- index_text begins -->
<li><A HREF="#mailbag/1"
><strong>Thank you for your telnet logging screen article</strong></a>
<li><A HREF="#mailbag/2"
><strong>LG</strong></a>
<li><A HREF="#mailbag/3"
><strong>install</strong></a>
<li><A HREF="#mailbag/4"
><strong>Security articles</strong></a>
<!-- index_text ends -->
</UL>
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="mailbag/1"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">Thank you for your telnet logging screen article</FONT></H3>
Thu, 21 Dec 2000 17:53:00 -0500
<BR>From: chris dillon &lt;<A HREF="mailto:gazette@ssc.com?cc:thebin@mailandnews.com"
>thebin@mailandnews.com</A>&gt;
<P>
I scoured the net and your article gave me the answer so that might log my
telnet session.
</P>
<P>
Thank you.
</P>
<HR width="10%" align="left"><P><em>
I've been doing a lot of abstract painting lately, extremely abstract. No brush, no
paint, no canvas, I just think about it.
-- Steven Wright
</em></P>
<!-- end 1 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="mailbag/2"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">LG</FONT></H3>
Fri, 1 Dec 2000 18:02:15 +1100
<BR>From: "BanDiDo" &lt;<A HREF="mailto:gazette@ssc.com?cc:bandido@drinkordie.com"
>bandido@drinkordie.com</A>&gt;
<P><STRONG>
LG is awesome, if you charged for it I would subscribe. When I
get some free time one of these I hope to pen a few articles and
such.
</STRONG></P>
<P>
Thanks. Linux Gazette was established as a free zine and we firmly
intend to keep it that way. There are already paid magazines out
there (we publish one of them
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">, but LG fills a unique niche. No
other e-zine I know of (Linux or otherwise) is read, not just
through a single point of access, but in large part via mirrors or
off-line (via FTP files, CD-ROMS, etc).
</P>
<P>
Also, because LG's articles are written by our readers, you
(readers) are truly writing your own magazine. I only put things
together and insert a few comments here and there, and occasionally
write an article. If it weren't for our volunteer authors, there
would be no Linux
Gazette. When I first took over editing in June 1999, I used
to wonder every month whether there would be enough articles. But
every month my mailbox magically fills with enough articles not
just for a minimal zine (5-10 technical articles), but for a robust
zine with 15+ articles covering a variety of content (for newbies
and oldbies, technical articles and cartoons). A year ago, we
never predicted there would be cartoons in the Gazette, but the
authors just wrote in and offered them, and it's been a great
addition. It is truly a privilege to work with such a responsive
group of readers, and years from now when I'm retired (hi,
Margie!), I'm sure I will remember fondly what an opportunity it
was.
</P>
<P>
Our biggest thanks go to The Answer Gang, especially Heather and
Jim, who each spend 20+ hours a month <em>unpaid</em> compiling The Answer
Gang, 2-Cent Tips and The Mailbag. This has really made things a
lot easier for me.
</P>
<p><em>Awwww, shux. I do get the occasional consulting lead from this,
though. -- <a href="mailto:star@starshine.org">Heather</a></em></p>
<P>
we look forward to printing some articles with your name on them.
See the Author Info section at
<A HREF="http://www.linuxgazette.com/faq/index.html#author"
>http://www.linuxgazette.com/faq/index.html#author</A>
</P>
<P>
And you other readers who haven't contributed anything yet, get off
your asses and send something in! Write a letter for the Mailbag,
answer a tech-support question, join The Answer Gang, do a
translation for our foreign-language sites, or write an article.
What do <EM>you</EM> wish the Gazette had more of? <em>That's</em> what it needs
from you.
</P>
<P>
--
Mike Orr
</P>
<P><strong>
Would be lovely if you guys established an EFNET irc channel
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
<br> -- BanDiDo
</strong></P>
<!-- end 2 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="mailbag/3"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">install</FONT></H3>
Sun, 10 Dec 2000 11:10:00 -0500
<BR>From: Ben Okopnik &lt;<A HREF="mailto:linux-questions-only@ssc.com"
>The Answer Gang</A>&gt;
<P>
On Sun, Dec 10, 2000 at 07:36:50AM <TT>-0000</TT>, &lt;Name Snipped&gt; wrote:
</P>
<P><BLOCKQuote>
&lt;A querent asked that we not publish his email&gt;
</BLOCKQuote></P>
<P>
If all you meant was not to publish your e-mail <EM>address</EM>, then please
write back with your question and be sure to clarify that. If not, then
consider this:
</P>
<P>
I can't speak for the whole Answer Gang, nor do I set Linux Gazette policy
- but I, for one, have absolutely zero interest in being a free
one-on-one tutor for the general public, although I'm always willing to
help my friends. I enjoy the fact that the effort I expend in answering
these questions goes toward helping everyone in the Linux community: even
those that don't read the LG benefit from the general dispersion of good,
useful Linux knowledge. This is precisely <EM>why</EM> I expend the effort, or is
at least one of my major motivations for doing so.
</P>
<P>
For anyone wanting one-on-one tech support and tutoring, it's "cash on the
barrel" in a "what you get is what you pay for" economy. Cash preferred,
bank checks are OK, major credit cards cheerfully accepted.
</P>
<P>
Ben Okopnik
</P>
<!-- end 3 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="mailbag/4"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">Security articles</FONT></H3>
Thu, 28 Dec 2000 09:54:31 -0800
<BR>linux-questions-only@ssc.com, Kapil Sharma <kapil@linux4biz.net>,<a href="mailto:linux-questions-only@ssc.com?cc:gazette@ssc.com">gazette@ssc.com</a>
<P>
[A guest commentary from our News Bytes editor. I asked him to
summarize the controversy on <A HREF="http://www.slashdot.org/">Slashdot</A> regarding SSH/SSL vulnerabilities,
and to assess whether we need an article on it. -Mike]
</P>
<P>
Date: Thu, 28 Dec 2000 16:55:56 +0000
Subject: Re: Late News Bytes additions
<br>From: Michael Conry <A HREF="mailto:michael.conry@softhome.net"
>michael.conry@softhome.net</A>
</P>
<P>
Hi Mike,
please find attached the
&lt;A HREF="lg_bytes61.html"&gt;news bytes 61 file&lt;/A&gt;.
I did go through the SSH issues, and summarised them briefly. I kind of
skirted around the SSL because it seemed less clear cut, and very much an
issue of implementation and protecting users from themselves. Most
discussion in the links focussed on SSH in any case.
</P>
<P>
I would recommend, not an article on Holes in SSH, but rather an article on
security in general. Lots of contradictory messages on Slashdot indicate
that people still don't really understand what is going on or how exactly to
administer a public key system.
</P>
<P>
The issues are not new, but are inherent in public key systems.
pgp,gnupg is the same (how can i be sure the key i think is yours is really
yours?). The biggest issue is probably users (lusers) ignoring warning
messages.
</P>
<P>
The new dsniff software is probably worth commenting on also. I included a
link in my short discussion, but have not studied it. What could be very
interesting would be for an article to highlight how to use tools like this
to strengthen your system/network by scrutinising it and probing it. Focus
tends to be on how these tools allow malicious people to break other
people's systems.
</P>
<P>
bye for now
<br>michael
</P>
<BLOCKQUOTE><EM>
[There were several other messages this month, but it's 10:45pm on New
Year's Eve, and I want to publish </EM>LG<EM> and get to the club by
12. The letters will be printed next month. -Mike.]
</EM></BLOCKQUOTE>
<!-- end 4 -->
<H4 ALIGN="center">"Linux Gazette...<I>making Linux just a little more fun!</I>"</H4>
<HR>
<center>
<table cellpadding=7><tr><td>
<IMG SRC="../gx/bytes.gif" border=1 ALT="News Bytes">
</td><td>
<H3>Contents:</H3>
<ul>
<li><a HREF="#distro">Distro News</A>
<li><a HREF="#general">News in General</a>
<li><a HREF="#software">Software Announcements</a>
</ul>
</td></tr></table>
<STRONG>Selected and formatted by <A HREF="mailto:michael.conry@softhome.net">Michael Conry</A></STRONG>
</center>
<P> Submitters, send your News Bytes items in
<FONT SIZE="+2"><STRONG>PLAIN TEXT</STRONG></FONT>
format. Other formats may be rejected without reading. You have been
warned! A one- or two-paragraph summary plus URL gets you a better
announcement than an entire press release.
<P> <hr> <P>
<!-- =================================================================== -->
<center>
<IMG ALT="Linux Journal 81 cover" SRC="misc/cover81.jpg" WIDTH=200 HEIGHT=268>
</center>
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<font color="green">
January 2001 <I>Linux Journal</I>
</font>
</H3>
<P>
The January issue of <A HREF="http://www.linuxjournal.com/"><I>Linux
Journal</I></A> is on newsstands now.
This issue focuses on Multimedia. Click
<A HREF="http://www.linuxjournal.com/lj-issues/81/index.html">here</A>
to view the table of contents, or
<A HREF="http://www.linuxjournal.com/subscribe/index.html">here</A>
to subscribe.
<FONT COLOR="green">All articles through December 1999 are available for
public reading at
<A HREF="http://www.linuxjournal.com/lj-issues/mags.html">http://www.linuxjournal.com/lj-issues/mags.html</A></FONT>.
Recent articles are available on-line for subscribers only at
<A HREF="http://interactive.linuxjournal.com">
http://interactive.linuxjournal.com/</A>.
<P> <BIG><STRONG>Vendors:</STRONG> <I>Linux Journal's</I>
2001 Buyer's Guide wants <EM>your</EM> product listings! Listings are
absolutely FREE of charge, however you must register your products by
<STRONG>January 15, 2001</STRONG>. The deadline is firm so make certain
to get your free listings in today. <A
HREF="http://www.linuxjournal.com/bg/">http://www.linuxjournal.com/bg/</A>.
</BIG>
<a name="distro"></a>
<p><hr><p>
<!-- =================================================================== -->
<center><H3><font color="green">Distro News</font></H3></center>
<P> <hr> <P>
<!-- =================================================================== -->
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Caldera
</FONT>
</H3>
<P> OREM, UT-December 19, 2000-
<a href="http://www.calderasystems.com/">
Caldera Systems, Inc., </a>
announced that they have contracted with Richard Sharpe of the Samba team to
create a client library that will make Linux and Microsoft integration
easier for developers. The Caldera-funded project includes the development
of library source code, associated reorganization and reuse of Samba code
and documentation of the library API.
The library and documentation will be available
under the General Public License (GPL). Caldera's engineering group will
work with the Samba team to complete the project by February 2001.
<p>
"Richard Sharpe is perfectly suited for this project," said John Terpstra,
vice president of technology and Open Source strategist for Caldera Systems,
"We believe this library built with Samba code will become the
standard for developers writing software that integrates with Microsoft
networks."
<p>
Developers interested in more technical detail on the project can
visit the
<a href="http://samba.org/samba">
Samba Web page.</a>
<P> <hr> <P>
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Mandrake
</FONT>
</H3>
<P> CAMBRIDGE, MASSACHUSETTS, USA (December 4, 2000) -
<a href="http://www.ics.com/">Integrated Computer Solutions, Inc. (ICS)</a>,
the leading supplier of commercial OSF/Motif
products and support, and MandrakeSoft, publisher of the Linux-Mandrake
operating system, announced the immediate availability of Open Motif
optimized for the Linux-Mandrake operating system.
More details are available in the
<a href=" http://www.ics.com/about/whatshot/press_releases/ome_mandrake.html">
press release
</a>
<p>
Open Motif optimized for the Linux-Mandrake 7.2 operating system is
available for free downloads at the MotifZone, ICS's Motif portal site
(<a href="http://www.motifzone.net">www.motifzone.net</a>). Open Motif is
also bundled with the Linux-Mandrake 7.2 PowerPack Deluxe.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Red Hat
</FONT>
</H3>
<P> RESEARCH TRIANGLE PARK, N.C.--December 11, 2000--
<a href="http://www.redhat.com">Red Hat, Inc.</a>
today announced that Cradle Technologies, Inc., is leveraging a broad set of
Red Hat's embedded technologies and services as part of its strategy to
supply a revolutionary silicon platform for stream processing applications.
<P> The Cradle contract
includes consulting services and porting of Red Hat's GNUPro embedded
development tools, eCos and embedded Linux operating systems, to Cradle's
Universal Microsystem platform (UMS). Cradle's UMS platform will make it
possible for new embedded systems to be developed simply by redesigning
software, rather than by constantly rebuilding the entire chip hardware.
<p>
<hr noshade width="20%">
<P> RESEARCH TRIANGLE PARK, N.C.--December 13, 2000--
In further embedded Linux developments, Red Hat announces a deal with
<a href="http://www.rymic.com">Rymic Systems</a>
that will put Red Hat Linux (uClinux) behind as many as 50,000
Army trucks and fighting vehicles. These vehicles will run a
next-generation Rymic appliance that assesses, in real time, the likelihood
of vehicle failure.
<P> The device will monitor dozens of specific variables on an array of
military vehicles, and provide decision-makers with additional information
when considering which forces to deploy, which fighting vehicles to pull
back from the battlefield and which vehicles require immediate maintenance
and repairs.
<p>
For more information on Red Hat Embedded Linux please visit
<a href="http://www.redhat.com/embedded">www.redhat.com/embedded</a>.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">SuSE
</FONT>
</H3>
<P> Oakland, Calif., USA (December 1, 2000) --
<a href="http://www.suse.com">SuSE Linux</a>
announced a new strategic alliance with SGI.
Under the alliance agreement, SGI will make an equity investment
in SuSE Linux and will co-operate on the development, deployment and
support of the Linux operating system and infrastructure code.
<P> Earlier this year, the companies successfully introduced Linux FailSafe, a
scalable and modular high-availability solution based on IRIS FailSafe system
software developed for the SGI IRIX operating system. Linux FailSafe offers
advanced clustering capabilities to Linux. SuSE, SGI and others also
cooperated in the highly regarded IA-64 Trillian Linux effort.
<p>
<hr noshade width="20%">
<P> SuSE have also brought it to our attention that
there is integrated backward-compatible Pentium 4 recognition in the
standard Linux kernel 2.2.16 included in SuSE Linux 7.0.
A boot disk image of the kernel can be downloaded from
<a href="ftp://ftp.suse.com/pub/suse/i386/update/7.0/kernel/pentium4/p4-bootdisk">
their ftp site
</a>
<a name="general"></a>
<p><hr><p>
<!-- =================================================================== -->
<center><H3><font color="green">News in General</font></H3></center>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Upcoming conferences and events
</FONT>
</H3>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">SSH/SSL Vulnerability
</FONT>
</H3>
<p>
There have been a few articles going around regarding possible security
risks associated with the use of SSH and SSL. Kurt Seifried has written
several times on this subject, as far back as
<a href="http://www.securityportal.com/closet/closet19990930.html">
September 1999</a>. More recently he has returned to the topic in
<a href="http://securityportal.com/cover/coverstory20001218.html">
an article</a> on
<a href="http://www.securityportal.com/">www.SecurityPortal.com</a>, and a
<a href="http://www.securityportal.com/seifried/sslssh-followup20001222.html">
follow up article</a> responding to some of the feedback he got from
readers. This topic seems to have stirred up quite a reaction, and has been
further
<a href="http://slashdot.org/article.pl?sid=00/12/18/0759236&mode=nested">
discussed</a> by the contributors to Slashdot.
<p>
Without wanting to repeat too much of the discussion that has gone before,
the issue basically boil down to one of key exchange and trust. The only
real risk to SSH security is in the initial contact with a machine when you
do not know whether it is in fact the host you think it is. This is not an
SSH problem, as such, but rather is a difficulty with any public key
encryption system. The trick is to find a secure way to distribute your
public key that does not inconvenience your users too much.
<p>
Also, the largest risk to security is not, in general, software problems. Many
problems actually originate from users who ignore or do not understand
warning signs that something is wrong. The problems with software
highlighted in these articles are the extent to which they leave themselves
open to poor use.
<p>
It is certainly worth pointing out that none of these links highlight any
NEW flaw in the SSH/SSL system or implementation. The main reason for the
recent focus on these issues is the release of a new piece of software:
<a href="http://www.monkey.org/~dugsong/dsniff/">
dsniff</a>, which makes easy interception of SSH traffic more convenient for
a wider number of people. This is not because it exploits any weakness,
rather it provides some handy tools to automate the interception process.
However, wide availability of these tools does increase the chance of casual
attacks on systems.
<p>
The take-home message is that the best way to keep a system secure is by
educating yourself your boss and your users about security. It is only by
understanding what is going on that you have any chance of keeping your system
healthy (hardly earth-shattering news, but true none-the-less).
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Linux Clusters Powering Genome Research
</FONT>
</H3>
<P> SALT LAKE CITY, UTAH, Dec. 14, 2000 -
<a href="http://www.linuxnetworx.com">Linux NetworX, Inc.</a>,
a provider of large-scale clustered computer solutions
announced that the Lawrence
Berkeley National Laboratory, Berkeley Calif., has selected a Linux NetworX
cluster computer system for its Drosophila Genome Project.
<P> Using the Linux NetworX cluster system with 40 processors, Berkeley Lab
is analyzing and sequencing the Drosophila (fruit fly) genome.
The Drosophila's 15,000 genes are similar to a human's 100,000 genes and
have been used extensively in the past as a model organism for research
studies.
<P> "The Linux NetworX cluster is much more cost efficient than the systems
we've used in the past," said Erwin Frise, systems manager and biomedical
scientist, Lawrence Berkeley National Laboratory. Frise also explains that
because clusters are highly scalable, Berkeley Lab will in the future be
able to add additional compute modules to the system to keep it up to date,
something not feasible with a supercomputer.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">New look for ShowMeLinux
</FONT>
</H3>
<P> Vancouver, British Columbia. December 1st, 2000 -
<a href="http://www.lutelinux.com">LuteLinux.com</a>,
a Canadian-based Linux developer announces
the unveiling of
<a href="http://www.showmelinux.com">ShowMeLinux</a>'s exciting new look.
LuteLinux had previously announced the addition of ShowMeLinux to their
family of services, LuteLinux is hosting all future issues and has taken
over as publisher of ShowMeLinux.
The new look was created by Adam Puchalski, a welcomed new addition to
both LuteLinux and ShowMeLinux, as their Graphic/Web designer, and
co-editor of ShowMeLinux.
<P> ShowMeLinux is published with the goal of helping readers develop an
in-depth understanding of the Linux movement through rich, beginner
friendly content. It explores practices for configuring, deploying and
maintaining the latest Linux technology.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">HP and Sprint PCS Form Wireless Email Alliance</FONT>
</H3>
PALO ALTO, Calif. and KANSAS CITY, Mo., Dec. 19, 2000 --
<a href="http://www.hp.com">
Hewlett-Packard</a>
and
<a href="http://www.sprintpcs.com">
Sprint PCS</a>
announced an agreement to jointly market and sell
the HP Openmail Anywhere solution as part of the Sprint PCS Wireless Web for
Business. The solution enables business customers to wirelessly access their
corporate email on Sprint PCS Internet-ready Phones.
Openmail is HP's strategic business messaging and collaboration solution
for Linux and UNIX(R) systems, based on Internet standards. More
information about Openmail is available at
<a href="http://www.hp.com/go/openmail">http://www.hp.com/go/openmail</a>.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Linux based BizRelations Inc. Announces First Fully Functional Wireless Email in time for Holidays
</FONT>
</H3>
Dec. 14, 2000 8:30am - BizRelations Inc.
(
<a href="http://www.BizRelations.com">WEB</a>
and
<a href="http://www.BizRelations.net">WAP</a>),
has announced Canada's first FULLY functional
and FREE Wireless Email system.
From any digital mobile phone equipped with wireless internet data
services users will be able
to Send and Receive emails, access their wireless
addressbook, check their email folders, and use the unique Quick
Reply Messaging function.
<p>
BizRelations have largely based their IT infrastructure on an Open Source
Linux foundation.
BizRelations has successfully been using the
<a href="http://www.linuxvirtualserver.org">Linux Virtual Server (LVS)</a>
along with
<a href="http://www.redhat.com/products/software/linux/haserver/">
RedHat's Piranha clustering tool</a>
to provide high availability and scalability for web, email and SQL services.
Sybase ASE 11.0.3.3 for Linux was the SQL server chosen by BizRelations,
while the email solution chosen was qmail
Another core function is monitoring the
availability of systems and networks.
To fill this requirement
<a href="http://www.netsaint.org">
NetSaint</a> was used.
"If there are any problems, an email gets sent to
the support cellphone stating the nature of the problem." says Patrick Petersen
(President of BizRelations).
After running with RedHat Linux for over a
year, even if Windows 2000 was a free alternative, BizRelations would
willingly shell out the money for Linux.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Linux Links
</FONT>
</H3>
<p>
<a href="http://www.salon.com/tech/feature/2000/12/01/wireless_ethernet/index.html">
Salon</a> take a look at free wireless TCP/IP networks in the US. The
originators see it as an extension of the Open-Source/Free-Software ethos.
<p>
ZD-Net take an in-depth look at running Linux on
<a href="http://lhd.zdnet.com/superguides/laptops.html">
laptops</a>. (For anyone wanting to turn their shiny new toy into a real
computer!)
<p>
<a href="http://www.newsforge.com/article.pl?sid=00/12/05/1145237">
Newsforge</a> comment on Bruce Perens' move to HP as head of the company's
Linux and open-source strategies. This is being touted as the first
Open-Source foray into the upper echelons of Big Business
<p>
<a href="http://www.eastbayexpress.com/archive/120100/cover_120100.html">
East Bay Express</a> looks at a life in a TelCo call centre. Makes you look
a bit differently at those frustrating periods on hold.
<p>
Some links courtesy of Slashdot:
<ul>
<li> NSA Linux distribution is discussed in a
<a href="http://slashdot.org/articles/00/12/22/0157229.shtml">
Slashdot article</a> and in a different tone on the
<a href="http://www.nsa.gov/selinux/">
official website</a> where, incidentally, you can download it for
yourself. Look it up soon, though, because they still aren't 100% sure
they can continue to distribute it.
<li>
<a href="http://www.lwn.net/2000/features/Timeline/?month=all">
Linux 2000 timeline</a>
<li> Turbolinux have demonstrated the use of a Linux cluster to crack
5-character NT passwords in just one minute. Read more
<a href="http://www.businesswire.com/webbox/bw.111300/203180468.htm">
here</a>.
(Please note, Turbolinux does not endorse breaking passwords,
they just like building good clusters!)
<li>A
<a href="http://www.lwn.net/2000/0113/a/ucita.html">
look</a>
at why UCITA is BAD. The issues are complicated, but this is a very
important issue to the future of software distribution and engineering.
</ul>
<a href="http://www.thedukeofurl.com">The Duke of URL</a> has some new
reviews that may be of interest to you:
<ul>
<li>For those wanting to keep in touch with the BSD side of things, the
Duke of URL has a
<a href="http://www.thedukeofurl.org/reviews/misc/freebsd42">
review</a> of
Free BSD 4.2 (even draws comparisons against Linux).
<li>The Finnish Software Engineering distribtion Best Linux
2000 R3 is out. Read the
<a href="http://www.thedukeofurl.org/reviews/misc/bestlinux2kr3">
review </a>
and find out how good Linux is in the homeland.
</ul>
<p>
The Linuxcare support Database is
<a href="http://www.linuxcare.com/help-yourself/kbsearch/simple-search.epl">
available online</a> if you have some problems you need solutions for.
<p>
<a href="http://www.osopinion.com/perl/story/5954.html">
OS Opinion</a> take a look at the difficulties with complicated software, in
particular the ramifications of OSX's UNIX/BSD heritage.
<p>
Some highlights from Linux Weekly News:
<ul>
<li>
If anyone is still in doubt what Linux IS, and would like a smile, check
out this
<a href="http://www.lwn.net/2000/1221/">
article</a>.
<li>
Those of an artistic temperament should look at
<a href="http://www.lwn.net/Gallery/">
Penguin Art.</a>
<li> Also, courtesy of LWN comes this link to
<a href="http://www.salon.com">Salon's</a> round up of tech
<a href="http://www.salon.com/tech/feature/2000/12/22/five_best/index.html">
stories and non-stories</a> of 2000AD.
</ul>
Finally, for the fashion conscious (or cold ;-),
<a href="http://www.tuxwear.net">Tuxwear</a> has a range of Linux apparel
(perfect treat to cheer one up in the post-Xmas season!).
<a name="software"></a>
<P> <hr> <P>
<!-- =================================================================== -->
<center><H3><font color="green">Software Announcements</font></H3></center>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">KDE 2.0.1
</FONT>
</H3>
<p><a href="http://www.kde.org">KDE</a> have announced release of KDE 2.0.1.
The official announcement is available
<a href="http://www.kde.org/announcements/announce-2.0.1.html">here</a>.
<p>
There is also a KDE Beta available for
<a href="http://www.lwn.net/2000/1221/a/kde-2.1b1.php3">
download</a>.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">XFree86 4.0.2
</FONT>
</H3>
<p>
<a href="http://www.xfree86.org/">XFree86</a> have released XFree86
4.0.2, and the
<a href="http://www.thedukeofurl.org">Duke of URL</a> has posted a
<a href="http://www.thedukeofurl.org/reviews/misc/xfree86402">
review </a>.
Highlights include ATI Radeon support.
<p>
For the official news, refer to the XFree86
<a href="http://www.xfree.org/#news">
news section</a>. Before you actually download or use this you will also
probably want to check out the
<a href="http://www.xfree.org/4.0.2/RELNOTES.html">
Release Notes</a>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Smart Batteries
</FONT>
</H3>
<P>
<a href="http://www.softtools.net">SoftTools Technology, Inc.</a>
has announced their new Linux Smart
Battery System Software Suite (Linux SBS3). The Linux SBS3
is a complete software solution for Portable systems that provides support
for systems that incorporate Smart Battery System components under Linux. A
User Friendly applet with a GUI for multiple smart batteries and/or regular
batteries that read and provide accurate information to the user is also
available.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Free Download of Configuration Management System Elego ComPact
</FONT>
</H3>
<P> The establishment of elego Software Solutions GmbH has been announced in
Berlin. The new company specializes in software configuration
management (SCM), and offers a wide range of support, service, and
general consulting in the area of configuration management (CM).
<P> Elego ComPact is a full-featured configuration management (CM) system
based on the well-known and reliable version control system CVS. Elego ComPact
extends CVS capabilities by adding new functions and concepts,
including build management and component model.
Elego ComPact may be used freely for all non-commercial purposes;
commercial users must obtain a license.
<P> Elego ComPact claims to add missing features and concepts to the basic
CVS system:
<P> You may download a current development snapshot of Elego ComPact
for evaluation purposes or free private use via FTP or HTTP from their
<a href="http://www.elego-software-solutions.com/download.html">
download page</a>.
<P> For more information see
<a href="http://www.elego-software-solutions.com">
www.elego-software-solutions.com</a>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">VMware Enters Server Market
</FONT>
</H3>
<P> PALO ALTO, Calif., December 5, 2000 -
<a href="http://www.vmware.com/">VMware, Inc.</a>.
For the latest VMware press releases, check out:
<a href="http://www.vmware.com/news/">www.vmware.com/news/</a>.
<P> VMware have made a number of announcements around two new server products:
<ul>
<li> - VMware Enables Intel Server Customers to Scale
their Internet Computing Infrastructures Safely,
Reliably and on Demand
<li> - VMware Announces Initial Adopters of its
New Server Products - CenterBeam, Inc.,
eOnline, Inc., Merrill Lynch, and ProTier
<li> - Compaq, Dell, IBM and VA Linux are Founding
Partners in VMware's Preferred Server Hardware
Vendor Program
<li> - VMware Forms Professional Services Organization
and Announces New Offerings to Ensure
Customer Success
</ul>
Rather than give all the details here, I will point you to the
<a href="http://www.vmware.com/news/">news</a>.
section of VMware's website where you can get the full stories.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">WARP Aim to Improve Web Performance
</FONT>
</H3>
<P> NEW YORK, NY * November 1, 2000 *
<a href="http://www.warpsolutions.com">WARP Solutions, Inc.</a>,
providers of Web
infrastructure software for the area of optimum
performance of Internet applications, have launched the WARP Performance
Suite, initially consisting of WARP Intelligent Content Distributor, WARP
Global Load Balancer and WARP Load Balancer.
Additional products - - WARP Dynamic Content Director, WARP Cache Master
and WARP Secure - - are being rolled out on an individual basis during the
fourth quarter and early next year. This suite of modules aim to
enhance web-server performance with emphasis on "performance, reliability,
scalability, security, speed and interoperability".
WARP's initial launch will
run on Solaris, Compaq Tru64 and Linux platforms.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">ACCESS Introduces Linux-based Browser Development Kit
</FONT> </H3>
<P> MILPITAS, Calif./TOKYO, Japan - December 11, 2000 -
<a href="http://www.access-us-inc.com/">ACCESS Co., Ltd.</a>
introduced a NetFront 2.6 Linux Software Development Kit (SDK) for the
worldwide market. This should speed the integration of ACCESS' popular NetFront
browser into Linux-based Internet appliances and other non-PC applications.
<p>
Since its introduction in 1995,
NetFront browsers have been shipped in over 18 million embedded devices from
40 manufacturers. NetFront is an ideal browser for Internet TVs, PDAs
(personal digital assistants), set-top boxes, car navigation systems, smart
phones, web/screen phones, vertical Internet terminals, video game consoles
and Internet kiosks.
<p>
The browser kernel
is less than 270 KB of code and fits in 1.3 megabytes of ROM and 2 megabytes
of RAM. It supports the full HTML 3.2 specification and selected portions of
HTML 4.0. It supports frames, JavaScript, cookies, web printing and
multilingual capabilities.
<p>
This SDK lets developers customize the user
interface to their desired look and feel and add plug-in applications
tailored for specific applications.
NetFront version 2.6 SDK for Linux will be available as a full source
code package. The SDK includes the NetFront version 2.6 browser kernel, a
sample user interface module and PIM suite, the Internet mail module, a
sample library for peer interface layer and graphics layer (GTK/SDL), and
documentation.
An SDK with five-seat development license is
available for $40,000 including three months support.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Linux-Based Intranet Broadcast Solutions
</FONT>
</H3>
San Jose, CA-
<a href="http://www.2netFX.com/">2netFX</a>,
a provider of streaming solutions for
intranet and broadband Internet media delivery, and
<a href="http://www.zapex.net/">Zapex Technologies, Inc.</a>
an industry leader of MPEG-2 compression
products, are in alliance to design and deliver innovative hardware
and software broadcast solutions to be used in the IP distance
learning market.
<p>
The first system offered by the alliance is a Linux-based server
solution, providing users a viable means to stream
broadcast-quality transmissions. It includes 2netFX's StreamRider
client and ThunderCast/IP server software and Zapex's ZL-330
encoder with Dolby digital audio and MPEG-2 video. It is the first
encoder of its type to achieve Dolby certification for Linux
operating systems, and it eliminates inherent lip-sync issues by
providing Transport Stream multiplexing within the Zapex encoder.
<p>
The ZL-330 produces high quality video images at low bit rates.
"The resulting low-bandwidth video stream from the ZL-330 permits
an unlimited number of users to access a multicast video," says
Gary Marsh, Zapex vice president of sales and marketing. "Coupled
with the 2netFX software, PC users can interactively select which
programming they wish to view, then capture and store the video
locally. Effectively, customers can select their own viewing
schedules, depending on application."
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Linux2order.com
</FONT>
</H3>
Eric Vogel has brought his new site
<a href="http://www.linux2order.com">Linux2Order.com</a>
to our attention. He describes it as "dedicated to
offering the largest collection of Linux applications available on the
Internet". A wide range of distribution methods are available. In addition
to the standard free download, the user can have a custom CD burned or
register for a priority download subscription.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Fox On Linux
</FONT>
</H3>
<p>
Fox on Linux is a commercial Linux application, providing
businesses with a sophisticated, graphical software package to deal
with their core financial accounting needs.
Fox on Linux can be integrated with other corporate front-end
applications and comes with online support and training. Flexible in its
operation, multi-user, and with a 12KBS low bandwidth requirement it can be
accessed over the Internet. Installation is claimed to be easy, so a system
can be up and running in a very short time.
For further briefing or a chance to trial Fox on Linux software go to
<a href="http://www.foxonlinux.com/">www.foxonlinux.com</a>.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Other Software
</FONT>
</H3>
<A HREF="http://www.tm.informatik.uni-frankfurt.de/~razi/steak/steak.html">
Steak: the Dictionary</A> is an English-German translation program with GUI
dialogs. (GPL)
<hr noshade width="20%">
Anyone interested in Electronic Design Applications, you might like to check
out <a href="http://www.yaeda.org">yaEDA</a>. It is available with
sourcecode.
<hr noshade width="20%">
<a href="http://www.provenacct.com">
PROVEN SOFTWARE, INC.</a> have announced the release of their new internet
shopping cart for linux, eCHOICE. This new feature will allow easy
integration with PROVEN CHOICE Accounting Systems. Full details are
<a href="http://www.provenacct.com/pr/echoice.html">here</a>, and an
evaluation copy is also offered.
<!-- *** BEGIN copyright *** -->
<P> <hr> <P>
<H5 ALIGN=center>
Copyright &copy; 2000, Michael Conry and
the Editors of <A HREF="mailto:gazette@ssc.com"><I>Linux Gazette</I></A>.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 61 of <i>Linux Gazette</i>, January 2001</H5>
<!-- *** END copyright *** -->
<P> <hr> <P>
<!-- ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: -->
<center>
<H1><A NAME="answer">
<img src="../gx/dennis/qbubble.gif" alt="(?)"
border="0" align="middle">
<font color="#B03060">The Answer Gang</font>
<img src="../gx/dennis/bbubble.gif" alt="(!)"
border="0" align="middle">
</A></H1>
<BR>
<H4>By Jim Dennis, Ben Okopnik, Dan Wilder, Chris Giamakopolous, the Editors of Linux Gazette...
and You!
<br>Send questions (or interesting answers) to
<a href="mailto:linux-questions-only@ssc.com">linux-questions-only@ssc.com</a>
</H4>
</center>
<p><hr><p>
<!-- endcut ======================================================= -->
<H3>Contents:</H3>
<dl>
<dt><a href="#tag/greeting"
><strong>&para;: Greetings From Heather Stern</strong></A></dl>
<DL>
<!-- index_text begins -->
<dt><A HREF="#tag/1"
><img src="../gx/dennis/bbub.gif" height="28" width="50"
alt="(!)" border="0"
><strong>Baffled</strong></a>
<dt><A HREF="#tag/3"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>A rather unique query (I hope)</strong></a>
<dt><A HREF="#tag/4"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
></a>info needed --or--
<dd><A HREF="#tag/4"
><strong>What is Linux?</strong></a>
<br>the screensavers look great!
<dt><A HREF="#tag/5"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>Linux Installation question</strong></a>
<dt><A HREF="#tag/6"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
></a>Abt.. Michael Lauzon's Q in issue 60.. --or--
<dd><A HREF="#tag/6"
><strong>Tell me about the K guys</strong></a>
<br>SCI-Linux project to use multiple package types?
<dt><A HREF="#tag/7"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
></a> minimum configuration Linux ? --or--
<dd><A HREF="#tag/7"
><strong>Data Recovery Vendor Seeks Linux Basics</strong></a>
RAIDs do not guarantee safety for your data
<dt><A HREF="#tag/8"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
></a>a question --or--
<dd><A HREF="#tag/8"
><strong>Linux, UNIX, what's the difference?</strong></a>
<dt><A HREF="#tag/9"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>linux question</strong></a>
<dt><A HREF="#tag/10"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>Red Hat 7.0</strong></a> Crackerz!
<dt><A HREF="#tag/11"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>Transmitting PaperPort files with .max</strong></a>
Definitely some Windows file format
<dt><A HREF="#tag/12"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>Help Me Delete Linux</strong></a>
<dt><A HREF="#tag/19"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>Removing Linux: Sacrilege!</strong></a>
<dt><A HREF="#tag/32"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
></a>uninstall linux --or--
<dd><A HREF="#tag/32"
><strong>Another uninstall: Getting to a Root Prompt to Blow it All Away</strong></a>
<dt><A HREF="#tag/13"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>setting root password</strong></a>
<dt><A HREF="#tag/14"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>I can't seem to write to my vfat (Windoze) file system with any user other than root.</strong></a>
<dt><A HREF="#tag/15"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
></a>For Jim Dennis...Hello from South Texas --or--
<dd><A HREF="#tag/15"
><strong>Firewall for a SOHO</strong></a>
<br>Small World, isn't it?
<dt><A HREF="#tag/16"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>Something comparable to Services in NT</strong></a>
<dt><A HREF="#tag/17"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>Editing fstab file for tape backup</strong></a>
<dt><A HREF="#tag/18"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>Mail gets nowhere?</strong></a>
<dt><A HREF="#tag/20"
><img src="../gx/dennis/bbub.gif" height="28" width="50"
alt="(!)" border="0"
><strong>Loading SuSE Linux 6.4 via NFS</strong></a>
<dt><A HREF="#tag/21"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>RE: classified disk</strong></a>
<dt><A HREF="#tag/22"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>multiple subnets, one DNS</strong></a>
<dt><A HREF="#tag/23"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
></a>Linux vs. DESQview??? --or--
<dd><A HREF="#tag/23"
><strong>responding to DESQview/386 Die Hards into the Next Millennia</strong></a>
<dt><A HREF="#tag/24"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>DOS partition from Linux</strong></a>
<dt><A HREF="#tag/25"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>e-mails not getting through</strong></a>
<dt><A HREF="#tag/26"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
></a>exit X & shutdown --or--
<dd><A HREF="#tag/26"
><strong>Exiting X and Rebooting with One Keystroke</strong></a>
<dt><A HREF="#tag/27"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>Multiplexing ppp connections</strong></a>
<dt><A HREF="#tag/28"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>[Tony@thermo-king.com: new to Linux]</strong></a>
<dt><A HREF="#tag/29"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>Trident Providia 9685</strong></a>
<dt><A HREF="#tag/30"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>The New network On The BLock</strong></a>
<dt><A HREF="#tag/31"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>Mail Daily sylog message to remote e-mail</strong></a>
<dt><A HREF="#tag/33"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
></a>automation for minicom --or--
<dd><A HREF="#tag/33"
><strong>Scripted Serial Sessions</strong></a>
<dt><A HREF="#tag/34"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
></a>About Epson Stilus Color 670 --or--
<dd><A HREF="#tag/34"
><strong>Setting up print filters.</strong></a>
<dt><A HREF="#tag/35"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>Xwindows</strong></a>
<dt><A HREF="#tag/36"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>diald on a smoothwall box</strong></a>
<dt><A HREF="#tag/37"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>...a bulk friendly ISP?</strong></a>
<!-- index_text ends -->
</DL>
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/greeting"><HR WIDTH="75%" ALIGN="center"></A>
<H3 align="left"><img src="../gx/dennis/hbubble.gif"
height="50" width="60" alt="(&para;) " border="0"
>Greetings from Heather Stern</H3>
<!-- begin hgreeting -->
<p>
Hello everyone, and welcome once again to The Answer Gang. As the fog starts
to lift this morning I am enjoying the fluffy greyness and savoring a good
cup of coffee. I leave it entirely to your imagination whether I'm talking
about the weather or my clouded thoughts.
</p><p>
We have some really juicy threads this month and I hope you like them. I'd
like to encourage anybody who feels like asking us questions, to consider
the following guidelines:
</p>
<ul>
<li>
Please use a real subject. We hate having to reply to "your mail" (the
classic default coughed up by our mailers, when replying to a blank subject
line). "Help" or "Linux trouble" is not much help to us. I know it sounds
strange, there's a batch of us here, but it will probably greatly increase
your chance of being one of the lucky souls who gets a direct answer. Try
actually stating your linux flavor, and what kind of trouble.
Examples: "RH 7 sound config?" "SuSE NFS install" etc.
<li>
This is a <em>Linux</em> webzine - ask us questions about free software.
For those of you from AOL, if the members' help forum can't answer you,
don't expect us to be any help at all (unless it's about Linux).
Windows has its own magazines and sites, and frankly most of the Gang hasn't
used Windows except in a cross-platform context in a long time.
<br>
That said, If you work for a Windows 'zine, you should really read one or
two of the items this issue...
<li>
Requests for anonymity are honored here. But if you don't want us to
publish your question and the answers, don't expect us to be interested in
helping you much. Several of us are consultants for a living, so unless it's
helping a few hundred people at once, we're not inclined to do freebies.
<li>
If you're using a foreign language and can manage to use an English subject,
please give a shot at asking your question in English, too. We're quite
forgiving of spotty English, if we can tell what you're asking. Otherwise
there's a couple of months lag while we have a translator look at your stuff,
if we even have someone to translate for your language. Babelfish is only
good for a laugh.
<li>
We reserve the right to be curmudgeonly. So flaming us for a lack of formality
will get you laughed at. We've also got ethics here and if you don't, you'll
get a serious drubbing. However, we don't bother publishing answers that don't
have some meat to them.
</ul>
<p>
Spam seems to be down this month, and I don't think we got any non-computing
questions this time around. Must be a Christmas present
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</p><p>
It's a new year and I look forward to some interesting New Year's resolutions.
In past years I've made selections such as 1600x1200 (the year I got the
beautiful monitor I use daily) and 600 dpi (a printer, of course)...
</p>
<!-- end hgreeting -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/1"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 1 -->
<H3 align="left"><img src="../gx/dennis/bbubble.gif"
height="50" width="60" alt="(!) " border="0"
>Baffled</H3>
<p><strong>From Patrick Green
</strong></p>
<p align="right"><strong>Answered By Jim Dennis
<br></strong></p>
<P><STRONG>
James I am at a loss here so I thought I would give you a try. I exited out
of a root session (not su) and I go back a couple hours later to login. I
enter my user name and lo and behold, no password prompt. So I cold boot it
(hate that) comes back up just fine, go to login ...no password prompt. Any
ideas?
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
First you'll want to get to a shell prompt. I'd treat this as
though your <TT>/etc/passwd</TT> or <TT>/bin/login</TT> files are corrupt. So,
start Linux using the init=/bin/sh kernel parameter (passed
from the LILO: prompt --- or LOADLIN, GRUB or whatever boot
loader you're using.
</BLOCKQUOTE>
<BLOCKQUOTE>
If that doesn't work, get out a rescue diskette or CD.
Remember Tom's (<A HREF="http://www.toms.net/rb"
>http://www.toms.net/rb</A>).
</BLOCKQUOTE>
<BLOCKQUOTE>
Once you've done that try to confirm that your <TT>/etc/passwd</TT>,
<TT>/etc/group</TT> and various <TT>/etc/pam.d</TT> files are sane. They
should "look right" (if you've seen copies before).
</BLOCKQUOTE>
<BLOCKQUOTE>
If you have backups of your <TT>/etc/passwd</TT> and <TT>/etc/group</TT> files,
restore them to an alternate location (<TT>/tmp</TT>) and run diff
on them. See if the differences seem reasonable.
</BLOCKQUOTE>
<BLOCKQUOTE>
If this is an RPM based system try the rpm <TT>-Va</TT> command
to verify the integrity of your <TT>/bin/login</TT> and other binaries.
(If you have a full tar backup of your root and <TT>/usr</TT> filesystems
you can use the 'tar df' or 'tar dzf' directives to report on
differences between your current files and those in your backup.
</BLOCKQUOTE>
<BLOCKQUOTE>
If you're running <A HREF="http://www.debian.org/">Debian</A> there are several ways to check the
integrity of your files; none of them is as easy to explain
and/or type as rpm <TT>-Va</TT> (that's one of the very few deficiencies
in the apt and dpkg systems). You can run debsums or tripwire or
aide if you have any of them --- but that's probably a matter of
closing the barn door while the horses are already astray in
this case.
</BLOCKQUOTE>
<BLOCKQUOTE>
There is a possibility that your <TT>/bin/login</TT> program is corrupt
or that an attacker has compromised your system and attempted
to replace <TT>/bin/login</TT> (or some other files) with a broken
version (perhaps linked against some library you don't have
even just having the wrong permissions or something like
that).
</BLOCKQUOTE>
<BLOCKQUOTE>
Of course I'd also check the <TT>/var/log/messages</TT> and related files
to see if there are any clues in there; do a fsck on your
root filesystem, try to run <TT>/bin/login</TT> from a rescue shell
prompt, etc. You can even temporarily replace <TT>/bin/login</TT> with a
one-line wrapper script. Rename it to login.binary or some such
an write a shell script like:
</BLOCKQUOTE>
<blockquote><pre> #!/bin/sh
exec /usr/sbin/strace -o /tmp/login.strace/$$.out /bin/login.binary
</pre></blockquote>
<BLOCKQUOTE>
... then try to login (rebooting as necessary, or just start
a shell on one of your virtual console with an appropriate
line in your <TT>/etc/inittab</TT> files).
</BLOCKQUOTE>
<BLOCKQUOTE>
It's an unusual problem, but these sorts of techniques will
help you narrow down what's happening.
</BLOCKQUOTE>
<BLOCKQUOTE>
(Obviously your kernel, your root filesystem and the init
program are working. Your getty seems to be working
enough to display an "issue" file and accept a username.
So we've already narrowed it down to getty and login ---
either getty is failing to successfully execute the login
command, or the login command is failing to emit a password
prompt. Since the latter is somewhat more likely we focus
on it.)
</BLOCKQUOTE>
<!-- end 2 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/3"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 3 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>A rather unique query (I hope)</H3>
<p><strong>From Karen Gartner
</strong></p>
<p align="right"><strong>Answered By Ben Okopnik, Mike Orr
<br></strong></p>
<P><STRONG>
Running RH 7 - Dell Precision 420, 18GB SCSI HD @ 10K rpm, 1 CD-ROM, 1
CD-RW, 19" screen w. Diamond Fire GL1 video card and therein is the start
of my problem.
</STRONG></P>
<P><STRONG>
The latest version of the Diamond fire GL1 driver for linux will only
work with kernel 2.2.14. RH 7 uses 2.2.16 so I have to backtrack to an
earlier kernel in order to use Gnome &amp; <A HREF="http://www.kde.org/">KDE</A> (I'm stuck in consoleland right
now).
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Interesting. The first possibility that I would explore would be to search
the web (or possibly contact the author) for a patch for the Diamond video
code, rather than downgrading the kernel. Chances are relatively high that
the necessary changes would be trivial (on the other hand, it may require
a major code rewrite, but it wouldn't hurt to check.)
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Indeed I have installed the new (old?) kernel but on booting, only 1 scsi
host is recognized where there should be 3, there's an IDE recognition
problem, and ultimately I get the message "kernel panic: VFS: unable to
mount root fs 08:02". I have checked lilo.conf and all is well there.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Well, the "kernel panic" message says that it's not finding a bootable
device/useable boot record on device 08:02 (if I recall correctly, that
means "device with major number 8, minor number 2", otherwise known as
"<TT>/dev/sda2</TT>", the 2nd partition of your 1st SCSI HD.) Is that what your
boot device is supposed to be? (side query: have you re-run "lilo"? It
never hurts to do so, and if you've changed <EM>anything</EM> having to do with
booting - and you have - you <EM>must</EM> do so.)
</BLOCKQUOTE>
<blockquote>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Not finding the <EM>root partition</EM> to mount. The boot sector is a different
story, and if you made it this far, it's functioning correctly.
</BLOCKQUOTE>
<BLOCKQUOTE>
At least your panic message has the word "root" in it. When it happens
to me, I get a cryptic "unable to open initial VC" (=virtual console) or
something like that. Because displaying a login: prompt requires a
virtual console, which requires a device in the <TT>/dev/</TT> directory, which
requires a root partition to be mounted.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
If you are unable to mount the root partition (you are correct in that
regard - I misspoke), I don't think that you will ever get anywhere near
the login prompt; the boot will fail at that point. It is true, though,
that a missing or damaged "<TT>/dev</TT>" directory will cause the "VC" message -
as will a "no virtual terminals" setting in the kernel configuration.
</BLOCKQUOTE>
</blockquote>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Where did the new (old?) kernel come from? If it's a "stock" RedHat
kernel, I would be rather surprised - RH compiles theirs with every bell,
whistle, and gilliwhillikin included. I certainly haven't had any fail to
detect SCSI hosts/devices, but that may just be because I've done only a
few "RH on SCSI" installations. I certainly have not had any SCSI
detection problems with <A HREF="http://www.debian.org/">Debian</A>, even SCSI-emulation setups (that being
what I have at home.)
</BLOCKQUOTE>
<BLOCKQUOTE>
If it's a kernel that someone else compiled, I would definitely check the
configuration... scratch that. I would not <EM>use</EM> a custom-compiled kernel
while bringing up a new system in the first place. I recommend that you
don't either.
</BLOCKQUOTE>
<BLOCKQUOTE>
By the way, are you certain that you should see 3 SCSI <EM>hosts</EM>, rather
than three SCSI <em>devices</em>? There is a difference, and it's an important
one. The host adapters are interfaces between the PC and the SCSI devices;
it would be exceedingly rare (if even possible) to find three of them in
one system.
</BLOCKQUOTE>
<blockquote>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
You should find out which device it's complaining about. Look in
Documentation/devices.txt in your kernel source. Block device 8:2 is
indeed <TT>/dev/sda2.</TT>
</BLOCKQUOTE>
<BLOCKQUOTE>
(You can also look in the <TT>/dev/MAKEDEV</TT> script, because this is the
script that made all those device files. However, I find it harder to
read.)
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
It's even easier to look in the "<TT>/dev</TT>" directory using Midnight Commander,
and scroll down until you see a match for those numbers. Possibly simplest
of all would be
</BLOCKQUOTE>
<blockquote><pre>ls /dev|grep "8, *2 "
</pre></blockquote>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Provided the <TT>/dev</TT> directory is there and is intact.
</BLOCKQUOTE>
<BLOCKQUOTE>
Note also that there are two types of devices, "block" and "character".
Disk drives are block devices. The same major number may be assigned
to one block device and a different character device.
</BLOCKQUOTE>
</blockquote>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
What I would like to do is take the config file from 2.2.16 and copy it
to 2.2.14. Everything but the video card works tickety boo in 2.2.16. The
problem is, where do I find the config file from 2.2.16? 2.2.14 is in
usr/src/linux of course, which was created on the install, but where does
the old .config file reside?
</STRONG></P>
<P><STRONG>
Is that even a good idea to solve the issue? Any and all help is mightily
appreciated.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
I would say that this is not a good idea at all. Configurations - and
thus, config files - vary wildly between kernel versions. On the other
hand, printing out the old configuration and walking through the new one
to make sure that it's as close as possible to the original would be very
useful. On my system (I'm running Debian, but I don't think it would be
very different on others), the config file is in
</BLOCKQUOTE>
<BLOCKQUOTE>
"<TT>/usr/src/kernel-source-</tt>&lt;version&gt;<tt>/.config</TT>"
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
This is the normal Linux convention. Actually, you can place your build
tree anywhere, but you should make <TT>/usr/src/linux</TT> a symlink to it so
that the compiler will find the include files. (Is this still required
now that glibc has its own kernel headers?)
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Good luck in resolving your problem.
</BLOCKQUOTE>
<!-- end 3 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/4"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 4 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>What is Linux?</H3>
<H4 ALIGN="center">the screensavers look great!</H4>
<p><strong>From David Cruz
</strong></p>
<p align="right"><strong>Answered By Mike Orr, Heather Stern
<br></strong></p>
<!-- ::
What is Linux?
~~~~~~~~~~~~~~
the screensavers look great!
:: -->
<P><STRONG>
i live in south africa and find it hard to source help from anyone here.i
recently saw a friend how is running his pc on linux software.very
impressive.i myself have windows 2000,which works well but when it comes to
graphics and proffessional look you're way ahead.i've been trying hard
searching the net for the last week for your softwear but came up with
nothing.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
The following URLs contain material on what Linux is, what you can do
with it, and where to find it:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQuote>
<A HREF="http://www.linuxresources.com"
>http://www.linuxresources.com</A> , sections:
</BLOCKQuote></BLOCKQUOTE>
<BLOCKQUOTE>
<UL>
<LI>"What is Linux"?
<LI>"About Linux distributions" (general information)
<LI>"Linux distributions" (information about each major distribution)
<LI>"GLUE" (look for a Linux users group in South Africa)
</UL>
</BLOCKQUOTE>
<BLOCKQUOTE>
<A HREF="http://www.linuxdoc.org/HOWTO/META-FAQ.html"
>http://www.linuxdoc.org/HOWTO/META-FAQ.html</A>
This is the Linux Meta-HOWTO, which gives an overview of where to find
different kinds of Linux information.
</BLOCKQUOTE>
<BLOCKQUOTE>
<A HREF="http://www.linuxdoc.org"
>http://www.linuxdoc.org</A>
Home site for Linux documentation. Click on "mirrors" and find a mirror
in South Africa to read; it will be faster and cheaper than using the
USA server.
</BLOCKQUOTE>
<BLOCKQUOTE>
<A HREF="http://www.linuxnewbie.org"
>http://www.linuxnewbie.org</A>
A site dedicated to helping new Linux users and those who just want to
see what Linux is before deciding whether to run it.
</BLOCKQUOTE>
<BLOCKQUOTE>
<A HREF="http://www.linuxstart.com"
>http://www.linuxstart.com</A>
A site which tries to be a "user-friendly index of Linux information".
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
.the one thing i
found incredible was your screensavers- radar, bumps(the blue torch
searching in the dark,compass
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Does anybody know which programs he's talking about? Is it the standard
X screensavers (xlockmore), the xscreensaver package, or something that
comes with <A HREF="http://www.kde.org/">KDE</A> or Gnome?
</BLOCKQUOTE>
<BLOCKQUOTE>
I don't use screensavers; I prefer to make the screen go black and switch
to power-saving mode. If I want to watch "eye candy", I'll run an
application which does this. Fortunately, xscreensaver screen savers can
also be run as applications in their own windows, not just as screen savers.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
The radar screensaver he is talking about is one of the utilities which
can be used as an xscreensaver module, or simply run as a seperate app.
By default it just looks cute, but it has command line options to "ping"
some specified hosts your local network and thus be more realistic "sonar"
for your situation. Several of the nicer toys like this need to be fetched
seperately from xscreensaver package itself.
</BLOCKQUOTE>
<BLOCKQUOTE>
Gnome uses a GTK based front end to xscreensaver, which shows a number of
these sorts of descriptions, including for the extras (it mentions their
homesites, so you know where to get them from. Maybe handy even if you
hate Gnome?) I have to say it was useful when I was trying to decide
which modules to not bother using. I don't really like the idea of a <EM>truly</EM>
random screen toy, as some of these artsy things are just plain ugly.
</BLOCKQUOTE>
<BLOCKQUOTE>
I don't remember what K uses. Anyways asking whether a given module is in
xscreensaver or in xlockmore is a lost cause. The two are always in a race
and at any given time, both have lots of cool eye candy, and a lot of it is
GPL so you could port it if you felt like. You can have both installed, but
only run one or the other at a time.
</BLOCKQUOTE>
<!-- end 4 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/5"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 5 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Linux Installation question</H3>
<p><strong>From Layne Gossett
</strong></p>
<p align="right"><strong>Answered By Mike Orr, Heather Stern
<br></strong></p>
<P><STRONG>
Is there an option for specifying that I would like to be prompted for all of
the kernel options during installation, much like you get when building your
own kernel?
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
I assume that by "during installation" you mean you want to customize
the kernel options at each boot, not the first time you install Linux
using your distribution's install program.
</BLOCKQUOTE>
<BLOCKQUOTE>
You cannot set the compile-time options (=the "make menuconfig" options)
at boot time. However, there are lots and lots of other kernel options
you can set from the LILO: promit or by adding an
</BLOCKQUOTE>
<BLOCKQUOTE><code>
append="myoption1 myoption2=myvalue1,myvalue2"
</code></BLOCKQUOTE>
<BLOCKQUOTE>
line in <TT>/etc/conf.lilo</TT> and re-running lilo. See the Bootprompt-HOWTO
for all the options you can set.
<A HREF="http://www.linuxdoc.org/HOWTO/BootPrompt-HOWTO.html"
>http://www.linuxdoc.org/HOWTO/BootPrompt-HOWTO.html</A>
</BLOCKQUOTE>
<BLOCKQUOTE>
Some other options can be set at runtime via the <TT>/proc</TT> filesystem. For
instance,
</BLOCKQUOTE>
<BLOCKQUOTE><code>
echo 1 &gt;/proc/sys/net/ipv4/ip_forward
</code></BLOCKQUOTE>
<BLOCKQUOTE>
will turn on IP forwarding. Echoing a zero will turn it off.
Documentation for these files is in the appropriate subsystems' docs and
HOWTOs. (And actually, most are not documented very well.)
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Although I have read the HOWTOs on building my own kernel, I still have not
been able to get it to work out yet. I've had a lot of luck installing Red
Hat from the CD, but I'd like to have firewalling and IP Masq capabilities
from a "clean" installation (and remove things like PCMCIA, etc.).
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
For masquerading, you must compile the kernel with IP forwarding and IP
masquerading. Then you need to enable it in one of your boot scripts.
For instance, my <A HREF="http://www.debian.org/">Debian</A> <TT>/etc/init.d/rc.firewall</TT> contains:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQUOTE><CODE>
/sbin/modprobe ip_masq_ftp # Only neded if masquerading non-passive FTP.
<BR>echo "1" &gt; /proc/sys/net/ipv4/ip_forward # Turn on IP forwarding.
<BR>/sbin/ipchains -M -S 7200 10 160 # Debian default timeouts.
<BR>/sbin/ipchains -P forward DENY # Deny any other kinds of forwarding.
<BR>/sbin/ipchains -A forward -s 10.0.0.0/8 -j MASQ
<BR># Masquerade from the 10.0.0.0 network to the outside world.
</CODE></BLOCKQUOTE></BLOCKQUOTE>
<BLOCKQUOTE>
Try running these commands manually and see if you can get masquerading
working with your current kernel.
</BLOCKQUOTE>
<BLOCKQUOTE>
For more security, you can build a more elaborate set of ipchains rules.
(Note: ipchains requires a 2.2.x kernel, which I assume is what you
have.)
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
The Debian installer does ask about these things, but just to prepare
the modules listing, not to prepare a whole kernel. And its prompts are
rather wimpy - you really have best luck if you already know what you are
looking for.
</BLOCKQUOTE>
<!-- end 5 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/6"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 6 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Tell me about the K guys</H3>
<H4 ALIGN="center">SCI-Linux project to use multiple package types?</H4>
<p><strong>From Manoj Warrier
</strong></p>
<p align="right"><strong>Answered By Heather Stern, Mike Orr
<br></strong></p>
<!-- ::
Tell me about the K guys
~~~~~~~~~~~~~~~~~~~~~~~~~
SCI-Linux project to use multiple package types?
:: -->
<P><STRONG>
Dan is right. Use one of the user friendly, mouth feeding distros
and U stay a newbie unless U make a habit of reading the Linux
Gazette and Linux Journal articles out of curiosity as to what happens
under the hood...
</STRONG></P>
<P><STRONG>
But, my ears picked up at Heather's comment <TT>-&gt;</TT> "I think the K guys
have the right idea, writing a front end that deals with more than
one package type". It sounds exactly like something I need. We are
compiling a set of software (most of the links provided at
"<A HREF="http://Scilinux.freeservers.com"
>http://Scilinux.freeservers.com</A>") which we think go into making an
Enviornment for scientific computing on Linux. We plan to make a CDROM
by April 2001 (GPL) with the sources <TT>/</TT> RPMs <TT>/</TT> other binaries and have
a Tcl/Tk interface to install these on a existing Linux/GNU PC.
We are still wondering if there is "a front end GUI that can deal with
more than 1 pacakage type".
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
kpackage is allegedly able to deal with both .deb and .rpm package types.
I assume that you still need the underlying libraries, so it knows what to
call. It may also be strongly dependent on alien, a script which eases the
conversion between package types.
</BLOCKQUOTE>
<BLOCKQUOTE>
If you're going to write your own GUI, definitely take a look at alien, the
packaging APIs, and the apps which already exist to deal with these package
types alone. Just make sure not to mix licenses in any incompatible ways...
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
So who are this K guys? <A HREF="http://www.kde.org/">KDE</A> develoment team? ...
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
Yes. The full name of KDE is "the K Desktop Environment" where according
to the FAQ, K stands for Kool. But they refer throughout their docs to K,
for example, the K menus, the K button, etc.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Of course, it was named after CDE, the Common Desktop Environment GUI
that many commercial Unices use.
</BLOCKQUOTE>
<p><em>... to which Manoj replies ...</em></p>
<P><STRONG><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Hi and thanks,
</STRONG></P>
<P><STRONG>
Elaborating more on my task at hand,
</STRONG></P>
<P><STRONG>
Work to be done <TT>-&gt;</TT> Create a CDROM with scientific software which can
be installed on a PC already running Linux.
</STRONG></P>
<P><STRONG>
Problem faced <TT>-&gt;</TT> There are various distros of Linux, various versions
of Linux software, therefore a binary which works on one may not
work on the other.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
This is more a matter of the library dependencies than the limits of
any one distro. ldd &lt;binaryname&gt; would tell you which libraries it
expects, and if those are really already present, you can force it to
install, over its packagemaneger's objection, and it will work.
</BLOCKQUOTE>
<blockquote>
<p><strong><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
(1) Thanks. I did not know this.
</strong></p>
</blockquote>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
In some cases the kernel may lack something, in which case providing a
usable kernel with modules would be a good idea. Don't forget pcmcia
modules and setup if you want to gracefully handle laptops.
</BLOCKQUOTE>
<blockquote>
<p><strong><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Not planning on this (at least not in the pre-alpha version). Also
wondering where I can keep the CDROM for free downloading (Power cuts,
etc, are quiet common this place).
</strong></p>
</blockquote>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Policy <TT>-&gt;</TT> Do not want to creae another distro of Linux (Linux from
scratch is the way to do it ... am I right??) on which we can then
make pre-compiled binaries.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
Sort of contrary to this, people call "Bastille Linux" a distro even
though it's strictly symbiotic to RedHat. You might look at Rock Linux
(designed to put the whole thing together from sources) or piggyback on
<A HREF="http://www.slackware.org/">Slackware</A> (which was an early distro, and is pretty strong in the compiler
department) or on debian (if it's got the packages you want already, since
it has so many).
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Therefore plan <TT>-&gt;</TT> Have the sources, binaries (*.rpm, slackware *.tgz,
*.deb, etc..) on a CDROM and have a Tcl/Tk script to install your
choice. The script would try to compile the sources for your Linux
distro if none of the binaries packed with the CDROM works for you.
I realise that a script that compiles from source for your distro of
linux will take a loooooot of time, and it is close to impossible
to make it work for all distros .. SO ANY IDEAS??
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
with the aid of alien I use rpm's on my debian box and .deb's on my <A HREF="http://www.suse.com/">SuSE</A>
box fairly freely. Admittedly I did grab 3 deb's to bring lynx-ssl over
but it was worth it... and not very hard, debian's dependency tree was
accurate.
</BLOCKQUOTE>
<blockquote>
<p><strong><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
(2) Using alien seems to be a stop gap solution ( I still have to check it
out ).
</strong></p>
</blockquote>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
If you also provide the basic libraries that your packages expect, and you
are <EM>really</EM> careful about adding them, you could do okay. The tricky part
is things like libjpeg6a versus libjpeg6b (for example). If you get some
app that really only wants a specific libary and nothing else will do, you'll
have to use LD_PRELOAD variables.
</BLOCKQUOTE>
<blockquote>
<p><strong><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
(3) Hopefully we will not need to use LD_PRELOAD. Providing basic libraries
is most appealing (after using ldd "binaryname" to find the library
dependencies for all the softwarewe plan to pack).
</strong></p>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
The point of using LD_PRELOAD would be if using this with an unknown locally
installed system - if your users will be booting from your CD-ROM, then you'll
know their environment is correct, and LD_PRELOAD will be unnecessary.
</BLOCKQUOTE>
</blockquote>
<BLOCKQUOTE>
You can use them anyway, and keep all your known support libraries in a little
link farm, or something. Probably don't even need hardlinks.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Why go into it at all <TT>-&gt;</TT> At my Institute (Insttute for plasma research,
Ahmedabad, India) we have a lot of ppl using Linux and most of them
do not have Octave, Scilab, Numerical libraries, yorick, xfig, lyx,
AbiWord, pvm, mpich, ftncheck, etc. etc. etc... on thier Linux PCs.
It would be convinient to therefore have a CDROM which would install
these on thier PCs.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
Just offhand I've seen most of those in a debian capt list. Make note,
I do point at non-free and non-US, so you may need to do that, or fight
licensing hassles, to distribute them.
</BLOCKQUOTE>
<blockquote>
<p><strong><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Never used <A HREF="http://www.debian.org/">Debian</A> (Indian PC mags have never given a free version). Here
RedHat sems to rule the roost. We get at least 2 CDROMS every year..
</strong></p>
</blockquote>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Another problem is getting started using these new
software. Detailed 100+page manuals are very useful after you get
started. therefore we have plans of short getting started guides for
these software. I guess there are other people who also might find
such a CDROM useful. Thats why we started this.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
All my best wishes go to you, the Linux world needs more documenters
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Meanwhile Ill be exploring alien and kpackage. kpackage would probably
need the underlying libraries ... Not everybody has this.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
There are tricks for unwrapping an rpm or a deb without having the library
installed yet. The <A HREF="http://www.linuxcare.com/">Linuxcare</A> Bootable Business Card (BBC) does this to
install ssh on-the-fly since when they began the project, the U.S. still
had overly eager anti-crypto laws. (It can be argued that they're still
rather crazy - see the EFF - but I'll leave that be for now.) You can get
the BBC at its new site: <A HREF="http://open-projects.linuxcare.com/BBC"
>http://open-projects.linuxcare.com/BBC</A>
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Which leads me to ask <TT>-&gt;</TT> Dont youll think fondly
about the window manager which you could work on within 5 seconds
of typing "startx" at your console on your 16 MB RAM 486? This
could be a silly sentiment ...
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
I recommend looking at fvwm2, it's what I use for a lightweight setup that
still offers "normal" menus. And flwm (fast light window manager) comes
highly recommended from the debian-laptops mailing list.
</BLOCKQUOTE>
<blockquote>
<p><strong><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
I use fvwm. flwm sounds good. Must check it out.
</strong></p>
</blockquote>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
If you're going to write your own GUI, definitely take a look at alien, the
packaging APIs, and the apps which already exist to deal with these package
types alone. Just make sure not to mix licenses in any incompatible ways...
</BLOCKQUOTE>
<blockquote>
<p><strong><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
and YES !! we have to check out licenses in detail (the least attractive
part of the project), but I guess we might be able to distribute most of
it since this is never going to be a commercial CDROM. Ill put it up
for free downloading (Is there anyone who will provide this service -
A mount point for a CDROM having a tar gzipped version of it?). Dont know
if I can convince my Institute to CDwrite and mail the CDROM to whoever
requests it and pays mailing charges. In fact dont know if anybody will
want it, but we learn quiet a lot (ldd "binary name", alien, etc..)
doing this.
</strong></p>
</blockquote>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Thanks once again.
</STRONG></P>
<P><STRONG>
Manoj
</STRONG></P>
<p><em>
Then there was this great - user friendly OS which
overwrote your MBR whenever you installed it...
</em></p>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
You're welcome, and good luck in your project.
</BLOCKQUOTE>
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/7"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 7 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Data Recovery Vendor Seeks Linux Basics</H3>
<h4 align="center">RAIDs do not guarantee safety for your data</h4>
<p><strong>From Support
</strong></p>
<p align="right"><strong>Answered By Jim Dennis, Mike Orr
<br></strong></p>
<!-- ::
Data Recovery Vendor Seeks Linux Basics
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
:: -->
<P><STRONG>
I wonder if you could point me to a FAQ that would answer the
following question:
</STRONG></P>
<P><STRONG>
We are a small company specializing in Data Recovery. HardDisk
"crashes" and the like.
</STRONG></P>
<P><STRONG>
We have a client that used a network Disk Drive from a company
called NETGEAR. It appears that they have built their product
round Linux (The good news !)
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
Yes. I've heard that the Netgear NAS (network attached storage)
products use an embedded Linux system). However I don't know
any details about their configuration.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
I have a bit of sympathy in my heart for data recovery companies,
because we had to use one at the hospital I worked at in 1994. I was
doing data entry into a FoxPro database and the Novell server crashed.
To top it off, this was 3pm on Christmas Eve and most people were gone.
Troubleshooting proved that the server would reliably crash when
accessing the middle of certain files in the NetWare filesystem--and
these were the database data files.
</BLOCKQUOTE>
<BLOCKQUOTE>
It took a week to recover. We were between sysadmins and didn't have a
backup, because our disk capacity was 2 GB but our tape drive had not
kept pace -- it was still a measly 250 MB model. A guest sysadmin from
the hospital-wide pool came, did the standard bindery tests (akin to
fsck), called a couple consultants who didn't help, called a CNE but
didn't engage him since he wouldn't have done more than we'd already
done--but would have charged $50 anyway!
</BLOCKQUOTE>
<BLOCKQUOTE>
We discovered that disk mirroring is not always a good thing. The
mirror drive was supposed to be our backup. And it did backup well:
it backed up the corrupted data!
</BLOCKQUOTE>
<BLOCKQUOTE>
The sysadmin noted my comments about the hard drive making noises, and
wrote in a report, "It done sound like a car need bearings." We sent
the drive to OnTrack; they took it apart, charged $2000, and sent back a
tape containing all the files they could recover. Out of all the
consultants and CNEs we called, they were the only competent ones in
this whole process. They also sent back an amusing analysis report:
"Severe hard drive damage. Drive should be replaced." Duh!
</BLOCKQUOTE>
<BLOCKQUOTE>
We replaced both drives, because the other one was acting up too. Both
were part of a bad Maxtor batch that were causing problems in other
parts of the hospital as well. They had 12-month warranties, and the
drives were failing in the 11th or 13th months.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Thus far, we have regrettably no experience of Linux. I wish to
Install a minimum configuration of Linux on a Win98 test PC in
order that i may copy the data on their (undamaged) harddisk to
another FAT32 harddisk and thereafter backup to CD's.
</STRONG></P>
<P><STRONG>
Right now i'm downloading 2 * 675Mb of "Linux" in ISO format. I
doubt that i need 10% of it for this task, but i have no knowledge of
the required files to get a minimal system running.
Is there an FAQ that would explain to a willing but uneducated guy,
how to proceed.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
You don't mention <EM>which</EM> ISO images you're downloading. It's
probably excessive in any event. Generally you can install a
fairly full Linux distribution from one CD (the second CD on many
distributions contains source code and/or extra software, sometimes
including shareware and other "non-free" stuff (demoware, etc)).
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
1. how to install a minimum version of Linux
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
This is a very difficult question to answer given that you haven't
told me which distribution you're downloading. Distributions differ
more in their installation and initial configuration than in any other
regard.
</BLOCKQUOTE>
<BLOCKQUOTE>
It would also be difficult, even if you had provided this information,
since it requires essentially a chapter length exposition.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
If you want just a minimal Linux installation to just copy data off a
Linux partition, consider Tom's Root Boot. It's a minimal Linux system
on a bootable floppy, with the utilities needed in a typical rescue
situation. Our sysadmins swear by it for all manner of workstation
setup tasks.
</BLOCKQUOTE>
<BLOCKQUOTE>
<A HREF="http://www.toms.net/rb"
>http://www.toms.net/rb</A>
</BLOCKQUOTE>
<BLOCKQUOTE>
However, I echo Jim's statement that you need to know the basics of
Linux utilities in order to do an effective data transfer. Many people
have had to embark on an unanticipated self-taught crash course, but it
means spending a weekend with the HOWTOs and manual pages or a book.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
2. how to copy files from a Linux Partition on one disk to a fat 32
partition on a second disk.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
This part would be quite easy once you have Linux installed.
Linux support FAT32 and MS-DOS filesystems (including the VFAT
long filename support). So you'd use a command sequence
something like this:
</BLOCKQUOTE>
<blockquote><pre> mkdir /mnt/netgear
mkdir /mnt/windows
mount -t ext2 /dev/hdb1 /mnt/netgear
mount -t vfat /dev/sda1 /mnt/windows
cd /mnt/netgear &amp;&amp; cp -ax . /mnt/windows
</pre></blockquote>
<BLOCKQUOTE>
... this assumes that you have installed Linux unto your first
IDE drive (the master on the primary controller) which is called
<TT>/dev/hda</TT> under Linux. It therefore assumes that the hard drive
which you've extracted from the Netgear NAS unit is the second
IDE drive (slave on the primary IDE controller) which is called
<TT>/dev/hdb</TT> under Linux. This all presumes that you made the necessary
changes to the pin settings on your hard drives to get the hardware
working.
</BLOCKQUOTE>
<BLOCKQUOTE>
I also assume that you're using a SCSI disk (though you could use
a third or fourth IDE drive --- or even a fifth, sixth, etc).
<TT>/dev/sda</TT> is the first SCSI hard drive on any normal Linux system
(though this may change in the future, with devfs).
</BLOCKQUOTE>
<BLOCKQUOTE>
So, this example makes many assumptions about how you've
installed Linux and what hardware you have available. There are
<EM>MANY</EM> other ways to do this.
</BLOCKQUOTE>
<BLOCKQUOTE>
Other than that the example basically makes a pair of mountpoints
(places at which filesystem can be connected), mounts the
Netgear drive to one and the Win '9x drive/filesystem to another
changes to the top of the netgear directory tree and copies
everything on that filesystem (recursively) unto the VFAT partition.
</BLOCKQUOTE>
<BLOCKQUOTE>
Note: I'm also assuming that the Netgear is not functioning as a
NAS and that you're removing the hard disk from it and connnecting
it to one of your lab machines. That seems pretty obvious to me,
since you'd just attach to it via the network directly from a
Win '9x/NT box if the NAS services were working; right?
</BLOCKQUOTE>
<BLOCKQUOTE>
I'm also assuming that Netgear is using ext2 (the dominant Linux
native filesystem). If they're using Reiserfs or some other
filesystem --- then you'd have to do things a bit differently.
If that is the case; you'd be best advised to use the <A HREF="http://www.suse.com/">SuSE</A>
distribution which already includes support for Reiserfs ---
otherwise you'd have to patch and build your own custom kernels;
which is not a task to be undertaken by novices.
</BLOCKQUOTE>
<BLOCKQUOTE>
(S.u.S.E. is the only major distribution that already supports
Reiserfs. Netgear <EM>might</EM> have patched their system to support
it given that Reiserfs' "journaling" features would be <EM>very</EM>
desirable on any Linux-based headless NAS device!)
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
3. Am i inventing work unnecessarily. maybe there exist tools to
read Linux partitions and copy DATA to Fat32. Something in the
Style of Partition magic ( but to actually COPY files.)
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
There used to be a set of ext2 (Linux extended filesystem version
2) utilities for OS/2 and Win32 (NT and '9x). However I'm not
sure that they are the best for your purposes.
</BLOCKQUOTE>
<BLOCKQUOTE>
It would probably be best to buy a nice large hard drive
(6Gb or better), put it in one of your lab workstations,
install Linux from CD (I prefer <A HREF="http://www.debian.org/">Debian</A>; but S.u.S.E. might
be more to your liking --- S.u.S.E. is the most popular
distribution in Europe and has very good support for various
continental languages).
</BLOCKQUOTE>
<BLOCKQUOTE>
Once you have Linux installed and the Netgear drive attached
you can "dump" a raw (bitwise) image of the entire drive into
a single Linux file using a command like:
</BLOCKQUOTE>
<blockquote><pre> dd if=/dev/hdb of=/some/path/with/lots/of/free/space bs=1024k
</pre></blockquote>
<BLOCKQUOTE>
... or you could dump each filesystem/partition by using
the commands:
</BLOCKQUOTE>
<blockquote><pre> fdisk -l /dev/hdb
</pre></blockquote>
<BLOCKQUOTE>
... and then (for each of the partitions listed there:
let's say it's 1, 2, 3, <EM>5</EM> and 6; skipping 4 since it might/would
be the extended partiton container:
</BLOCKQUOTE>
<blockquote><pre> for i in 1 2 3 5 6; do
dd if=/dev/hdb$i of=/lots-of-space/netgear-image.hdb$i.bin
done
</pre></blockquote>
<BLOCKQUOTE>
(This last is a bit fancy for a novice. However, you can just
type the commands one at a time until that little snippet of
shell code makes sense). (Obviously you'll need to put in
your own names in place of the of= paths that I've listed here).
</BLOCKQUOTE>
<BLOCKQUOTE>
NOTE: if the netgear filesystems are larger than 2Gb then
you might need a very new kernel with LFS (large filesystem support)
or you could use "raw" partitions (unallocated space) on your
new large Linux disk.
</BLOCKQUOTE>
<BLOCKQUOTE>
This "dd" approach is handy if you want to preserve a full
snapshot of the filesystem (in it's damaged state) before attempting
data recovery. That way, if your filesystem check and repair
efforts cause <EM>more</EM> damage you can always start from scratch.
</BLOCKQUOTE>
<BLOCKQUOTE>
In general I'd say that there is <EM>way</EM> too much about Linux to
learn before you'd understand how to do filesystem or data recovery.
As I'm sure you know from your experience with FAT/VFAT/FAT32 based
filesystems, one must generally be expert in an OS prior to being
competant at data recovery under it.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
I would be most grateful for any advice you could offer.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
You could look for a good Linux training consultant to come
in and give you're team a crash course. You'll find that Linux
really is a data recovery person's dream tool suite. Although it's
not "easy to use" it does offer <EM>full</EM> access to the system
hardware and has very good support for the filesystems of various
operating systems.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
My best Christmas greetings from Sweden,
Tony Kvarnstrom
</STRONG></P>
<!-- end 7 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/8"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 8 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Linux, UNIX, what's the difference?</H3>
<p><strong>From Alex
</strong></p>
<p align="right"><strong>Answered By Heather Stern
<br></strong></p>
<!-- ::
Linux, UNIX, what's the difference?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
:: -->
<P><STRONG>
Hi, I have a question that's been on my mind lately.
I've looked around the web and gotten some roundabout
answers. The question is, what is Linux?
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
Linux began life as a kernel that would act like Minix but run on Linus'
80386 and mount up his minix filesystems. He shared it and was encouraged
by folks submitting their own patches. People just can't make their mouth
say "Linus' Minix" for very long, but I can't pinpoint when it got compressed
to Linux. Maybe one of our readers could
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Vaguely I recall Lars Wirzenius mentioning the origin of the
name Linux in a talk at Linux Expo 1998. I think he said something
like it wasn't Linus who came up with the name. He just uploaded it
to the FTP site and the FTP admin had to come up with a label for it,
so he called it Linux. But I may be remembering wrong.
</BLOCKQUOTE>
<BLOCKQUOTE>
Where's that message where Linus recounts how his first success in
building Linux was to develop a multitasker that allowed one process
to write "a" repeatedly to the screen while another process wrote "b"?
I think in there it mentions that one of his early names for the
system, when he was in an extremely frustrated mood, was Buggix.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
As time rolled on and "distributions" were gathered and sold, the press
likes to call the distributions Linux too, while others argue that only
the kernel is Linux and the rest is (for example) <A HREF="http://www.redhat.com/">Red Hat</A> or <A HREF="http://www.suse.com/">SuSE</A> or whatever.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
The most popular answer on the net seems to be "Linux
is a UNIX-like OS". Well, then what is UNIX? And why
isn't Linux UNIX?
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
There is someone who presently administers the trademark work UNIX and they
don't feel like branding Linux with it for free. <A HREF="http://www.freebsd.org/">FreeBSD</A> has the same
"problem" - both are at this point well established systems that people
already experienced in UNIX will find comfortable features in.
</BLOCKQUOTE>
<BLOCKQUOTE>
The trademark began life as AT&amp;T Bell Labs UNIX, and has been traded and
sold a number of times since. For a while Novell owned it ... in fact,
for a brief time it looked like Novell could become the source of a new,
completely non Microsoft based system, because they had Netware, they
had DR DOS, they had WordPerfect and its family of apps... but they either
didn't see it or had so many internal politics they couldn't do it.
</BLOCKQUOTE>
<BLOCKQUOTE>
The current trademark holders are the Open Group. Their babble about
rights to use their trademark is at:
<A HREF="http://www.unix-systems.org/trademark.html"
>http://www.unix-systems.org/trademark.html</A>
</BLOCKQUOTE>
<BLOCKQUOTE>
Anyways, UNIX shouldn't be used as a generic term, because that's against
the principles of trademark. Let me illustrate with an example that a few
more people will understand. You can't call something Coca-Cola
(<A HREF="http://www.coca-cola.com"
>http://www.coca-cola.com</A>) that's not. You're not supposed to call it Pepsi
either (<A HREF="http://www.pepsi.com"
>http://www.pepsi.com</A>, but you can't use the site at all from lynx;
try their investor relations site, <A HREF="http://www.pepsico.com"
>http://www.pepsico.com</A> instead) unless it's
really Pepsi. But you can call it a "Coca-Cola like soda" or say something
"tastes kinda like Pepsi" and you're safest with "a cola" or "a soda pop".
For the curious out there, I drink either, but prefer RC
(<A HREF="http://www.rccola.com"
>http://www.rccola.com</A>).
</BLOCKQUOTE>
<BLOCKQUOTE>
So Linux is "an operating system" which only "tastes like MS Windows" if you
select a window manager with a theme that tries really hard to do that,
but tends to "taste like UNIX". Admittedly it tastes a bit more like these
if you go the extra mile and run <A HREF="http://www.winehq.com/">WINE</A> or have the iBCS compatability module
around so you could try to run the respective binaries.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Funny, just today I saw a story in Linux Weekly News where Sun claims
Solaris is a version of Linux because it can run programs compiled for
Linux, and maddog says this proves we've never come to a consensus on
what "Linux" really means. Purists say Linux means just the kernel, but
maddog cites Linus as predicting that mainframes with highly-customized
kernels will also be "Linux sytems" in the future.
</BLOCKQUOTE>
<BLOCKQUOTE>
<A HREF="http://www.lwn.net/2000/1221"
>http://www.lwn.net/2000/1221</A>
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Is AIX or Solaris or SunOS or HP-UX a UNIX?
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
AIX and Solaris are blessed with this trademark under "UNIX 98", HP-UX and
Tru64 among others are blessed under "UNIX 95". (You can see the Open
Group's Registered Product Catalog if you care:
<A HREF="http://www.opengroup.org/regproducts/catalog.htm"
>http://www.opengroup.org/regproducts/catalog.htm</A>
</BLOCKQUOTE>
<BLOCKQUOTE>
I don't think SunOS ever got so blessed; it was a BSD derivitive after all.
You can read some about the confusions between SunOS and Solaris in this
handy note:
<A HREF="http://www.math.umd.edu/~helpdesk/Online/GettingStarted/SunOS-Solaris.html"
>http://www.math.umd.edu/~helpdesk/Online/GettingStarted/SunOS-Solaris.html</A>
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
If so, what makes them a UNIX and Linux <EM>not</EM>
a UNIX? Is it kernel specific? What's the deal?
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
I hope this helped.
</BLOCKQUOTE>
<!-- end 8 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/9"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 9 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>linux question</H3>
<p><strong>From Ted Mims
</strong></p>
<p align="right"><strong>Answered By Dan Wilder
<br></strong></p>
<P><STRONG>
I hope you can help me out. I am running a box with Linux 6.0. I had a
hacker a few weeks ago that primarily set up some shielded irc channels
and modified my dns for his needs (exactly what they were, I am not
sure). Anyway, somehow he made it so that my securetty file is ignored.
I am having no luck locking root out of telnet. securetty has the
correct format and permissions and pam_securetty.so is not commented in
the <TT>/etc/pam.d/login</TT> file. Do you happen to have any suggestions? All
I want to do is re-restrict direct-in root access. I would greatly
appreciate any elightenment you can offer. Thanks
</STRONG></P>
<P><STRONG>
Ted H. Mims
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Dan]
The executive summary: reinstall, secure the new system,
copy data from the old.
</BLOCKQUOTE>
<BLOCKQUOTE>
Unfortunately, once a system is compromised, you can't trust
the pieces. The skilful cracker, or even the less skilled
in this day of script kiddees, will have replaced system binaries
such as <TT>/bin/login</TT>, <TT>/bin/ls</TT>, <TT>/bin/ps</TT>, and on and on. This places
you in a shifting hall of mirrors when you attempt repair on a
running system. Especially if you attempt this repair while the
system is connected to the network. I know very few sysadmins
who would be up to this challenge, fewer still who would be
assured of success, and almost none who would attempt it except
on a wager or as a sport. I would be the last to suggest
you attempt this based on a few pointers.
</BLOCKQUOTE>
<BLOCKQUOTE>
The prudent course of action is a fresh install on a new hard drive.
Do this on a system without any connection to an outside network.
</BLOCKQUOTE>
<BLOCKQUOTE>
Upgrade named. <A HREF="http://www.isc.org/products/BIND"
>http://www.isc.org/products/BIND</A> is the URL.
Use bind-8.2.2 patchlevel 7 for an easy upgrade from what's on
most 6.0 distributions. Or, see if the ftp site for your
distribution has an upgrade. Eight bugs, including one
allowing remote exploit and providing the attacker with
full access at whatever privilege level named runs at, have
been located in older versions of bind.
</BLOCKQUOTE>
<BLOCKQUOTE>
Eliminate all services the system does not need, by turning them
off in <TT>/etc/inetd.conf</TT> or the equivalent xinetd config files.
</BLOCKQUOTE>
<BLOCKQUOTE>
Establish secure passwords for all accounts.
</BLOCKQUOTE>
<BLOCKQUOTE>
At that point, take the hard drive from the old system and mount
it for example on <TT>/mnt.</TT> Copy valuable data from the old hard drive
to the new. Examine all configuration files you may copy over
carefully.
</BLOCKQUOTE>
<BLOCKQUOTE>
Don't allow telnet from remote systems. The password is
transmitted in plaintext, not a very good idea in this
age of sniffers.
</BLOCKQUOTE>
<BLOCKQUOTE>
Consider instead installing ssh or openssh, if remote access
is needed, or if you're on a LAN with more than a handful
of hosts or with users who are not highly trusted employees.
Be aware that even ssh is not 100% proof against "man in the middle"
compromise.
</BLOCKQUOTE>
<blockquote>
<BLOCKQUOTE>
&lt;digression&gt;
That "6.0" doesn't mean much if you don't specify the distribution,
for example "<A HREF="http://www.redhat.com/">Red Hat</A>" or "<A HREF="http://www.suse.com/">SuSE</A>" Each Linux distribution
maintains its own versioning system, with only very rough
equivalence between distributions.
&lt;/digression&gt;
</BLOCKQUOTE>
</blockquote>
<p><em>.... Ted found the breakage ...</em></p>
<p><strong><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
I just needed to actually pen the question to someone. I figured it out
all by my lonesome. Thanks anyway. He had bypassed pam and sent it
back to the login.defs file which of course did not have a CONSOLE
directive.
</strong></p>
<p><strong>
Ted H. Mims
</strong></p>
<!-- end 9 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/10"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 10 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Red Hat 7.0</H3>
<h4 align="center">Crackerz!</h4>
<p><strong>From George Hawthorn
</strong></p>
<p align="right"><strong>Answered By Ben Okopnik, Heather Stern
<br></strong></p>
<P><STRONG>
Answer Guy,
</STRONG></P>
<P><STRONG>
I've searched every Linux site I can find to understand why after months of
trouble free operation, I am unable to login to my RH 7.0 server at the
terminal. Everything is working fine, web server, ftp, router but I simply
cannot login as root or anybody else for that matter. I can do a 'linux
single' boot but under a normal boot, when I get the login: prompt and type
root, I'm back at the login prompt again.
I realize this is an imposition, but I'm getting desperate.
</STRONG></P>
<P><STRONG>
Thanks for your time,
</STRONG></P>
<P><STRONG>
George Hawthorn
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
First, a quick possibility: Take a look at my
'<a href="../issue52/okopnik.html"><em>"Cannot execute <TT>/bin/bash:</TT> Permission denied" - solved!</em></a>' article in Issue #52 of the Linux Gazette.
It may contain an answer to your question. Note also that people <EM>are</EM>
able to log in if your ftp, etc. services are usable - they are logging in
as a very low-privilege user ("nobody", or "ftp"), but they <EM>are</EM> logging
in.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
Here's an even faster possibility (maybe even the same) - did you upgrade
PAM recently by any chance? The default files from a PAM upgrade usually
are not the same as your normal policy. One time I ended up only being
able to get in via ssh ... and that, only because my key was already in
place, so it wasn't dropping down to standard authentication.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Second - when you do log in via 'single', what does the system look like?
Has the password file changed? (Hint: it is a Good Idea to have dated
snapshots of "<TT>/etc</TT>" along with your regular backups; a tarred/gzipped
archive should easily fit on a floppy.) Try making a copy of "<TT>/etc/passwd</TT>"
(or "<TT>/etc/shadow</TT>" if you use shadow passwords), then edit it to remove the
password hash for root -
</BLOCKQUOTE>
<blockquote><pre>root:1XaFDYn7EapuP:0:0:root:/root:/bin/bash
</pre></blockquote>
<BLOCKQUOTE>
Chop out the second field:
</BLOCKQUOTE>
<blockquote><pre>root::0:0:root:/root:/bin/bash
</pre></blockquote>
<BLOCKQUOTE>
When you next log in as "root", you won't need a password - just make sure
to create one immediately. If you <EM>still</EM> cannot log in, then something in
the system itself is giving you problems; once again, refer to the above
article.
</BLOCKQUOTE>
<BLOCKQUOTE>
As to reasons <EM>why</EM> this happened in the first place: well, the scary-but-
obvious reason could be that some "script-kiddie" got into your system and
did a dance on it. Not to panic; as long as you've got good backups, the
damage can be undone (and if you're running a publicly accessible server
and _don't_ have backups, I'm afraid you've gone beyond any help I can
give.) It could also be that some program you've installed - and I haven't
heard of anything like this with progs from established distributions,
whereas just slapping in a random tarball could do this - has messed up
your libraries or other vital files.
</BLOCKQUOTE>
<BLOCKQUOTE>
In my experience with Linux, I've come to an expectation that I did not
have with MS Windows or OS/2 - "stuff" doesn't just happen. There <EM>is</EM> a
reason for this; whether a security problem caused by random services
enabled in "<TT>/etc/inetd.conf</TT>" (I strongly suggest reading the Security-HOWTO
if you have not done so previously) or a problematic program installation,
you need to track it down and resolve it. Particularly in the case of a
break-in, it is not something you want to happen again.
</BLOCKQUOTE>
<BLOCKQUOTE>
Good luck
</BLOCKQUOTE>
<p><em>... George adds some context ...</em></p>
<P><STRONG>
<img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Ben,
</strong></p>
<P><STRONG>
Thanks so much for the speedy reply. I'm going to read through your e-mail
very carefully. I can tell you that I've done nothing to the server for
months accept FTP files to it, Telnet to it, add a couple of users etc.
It's been running perfectly since August of this year, and so I "think" I
can rule out my actions as the cause. I haven't installed any additional
programs. As for the security issue, this was and still is my immediate
concern. I wonder if someone has got in and done "something". I did see a
couple of bad login attempts using lastb. I do have copies of ALL important
files, and so could simply reinstall the OS, but then I'd be no better
off...just waiting for it to happen again.
Thanks once again for your help. I'll let you know if I find the cause.
</strong></p>
<p><em>... then following Ben's advice, investigates more carefully ...</em></p>
<P><STRONG>
<img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Ben,
Following your article in issue #52, I looked at <TT>/bin/login</TT> (using linux
single) and noticed that it is owned by root and lp (have no idea what lp is
...sounds like a print queue).
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Just to hazard a guess - since I don't know the layout of your system or
anything else about it - an attacker may indeed have come in via your
remote print system; there are exploits (if I remember correctly) that use
it, since it requires a high level of privilege to access the hardware
ports. I would at least check into security measures involving the print
system - the first of which would be to make sure that I'm running "rlpr"
or "lprng" for my remote services. The second would most likely be a
search of COTSE &lt;<A HREF="http://www.cotse.com/unix.htm&gt"
>http://www.cotse.com/unix.htm&gt</A>;, Insecure.org
&lt;<A HREF="http://www.insecure.org/sploits_linux.html&gt"
>http://www.insecure.org/sploits_linux.html&gt</A>;, or NetworkICE
&lt;<A HREF="http://www.networkice.com/advice/Exploits&gt"
>http://www.networkice.com/advice/Exploits&gt</A>; for known exploits against
whatever I <EM>am</EM> running.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
I booted up another pc with RH 7.0 and
noticed that its <TT>/bin/login</TT> ownership is root and root. I tried chown
root.root login, but get the 'permission denied response'. I also edited
<TT>/etc/shadow</TT> with no luck. I agree with your theory that reinstalling
teaches you nothing. My master plan was to FTP the login "program" from a
working pc to the server in the hope that login is somehow corrupted on the
server.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
"<TT>/bin/login</TT>" and "<TT>/bin/bash</TT>" are typically good things to check when
looking for intrusion "footprints", especially a "<TT>/bin/bash</TT>" that's been
set SUID (this means that anyone running that shell has full root
privileges!) The fact that you're unable to chown "login" means that
FTPing a good "login" binary will not help - you probably won't be able to
delete the old one. In fact, it's a pretty strong indicator that...
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
I rebooted the server using the linux single command, and then SU to login
as root. I was scrolling through previous commands and was surprised to see
many commands that I didn't enter. Someone created a user called "Poped" as
far as I can tell, and then entered commands such as
</STRONG></P>
<P><STRONG>
rm <TT>-f</TT> <TT>/bin/login</TT>
chattr <TT>-i</TT> <TT>/bin/login</TT>
</STRONG></P>
<P><STRONG>
It would seem that someone gained access. What do you think?
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
...somebody got in. I assume I don't need to mention that you need to
immediately take your system off the network - given that he has root
access, your attacker could easily wipe out your entire system.
</BLOCKQUOTE>
<BLOCKQUOTE>
I would guess, even though you haven't mentioned this, that they ran a
"chattr +i" on the "<TT>/bin/login</TT>" that they had installed - this would be the
reason that you can't delete "<TT>/bin/login</TT>". You can remove the "immutable"
flag set by "chattr" by running "chattr <TT>-i</TT> <TT>/bin/login</TT>"; this should allow
you to delete/replace it with a non-'rootkit' "login".
</BLOCKQUOTE>
<BLOCKQUOTE>
By the way - one of the ways you can usually tell the replacements is by
looking at the size of the executable. The 'rootkit' types, due to the
fact that they can't be dynamically linked (they have to be able to work on
a system whether it has their required libraries or not), are normally much
larger.
</BLOCKQUOTE>
<BLOCKQUOTE>
In a way, you should consider yourself lucky - a really knowledgeable
cracker would have replaced your "<TT>/sbin/syslogd</TT>" and cleaned up your
logfiles. You would never have known that anyone had been in there. Also,
the very fact that he screwed up "login" to that degree shows him to be an
amateur - a successful system crack is nowhere nearly that obvious or
crude.
</BLOCKQUOTE>
<BLOCKQUOTE>
Once again, I strongly recommend reading the Security-HOWTO and doing some
research. Leave your system off-line until you're satisfied 1) that you
understand how the attacker got in, 2) have securely patched that hole,
and 3) have done a general security survey of your system and are
reasonably satisfied with its state. If you're setting up a publicly-
accessible server and have not studied the security aspect, you're letting
yourself in for a large heap of trouble - as you have found out.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Thanks for any help.
</STRONG></P>
<P><STRONG>
P.S. so much for my firewall.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Ah, <EM>more</EM> reading to do!
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle"> Firewall setup is not as "automatic" as a lot
of folks think. Most of the time, it's not particularly difficult - but it
<EM>does</EM> require attention and a bit of study. See the (are you surprised?)
Firewall-HOWTO.
</BLOCKQUOTE>
<p><em>... George will go one better ...</em></p>
<P><STRONG>
<img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Ben,
I'm really grateful for your excellent responses. You've been a tremendous
help and I plan on taking your advice. I bought "Building Linux and Open
BSD Firewalls" a few months ago and will delve more deeply into the book.
</STRONG></P>
<P><STRONG>
Happy Christmas, and thanks once again.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Glad I could be of help, George; sounds like you're taking an effective
tack to resolve the problem. Merry Christmas to you as well, and the best
of luck.
</BLOCKQUOTE>
<!-- end 10 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/11"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 11 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Transmitting PaperPort files with .max</H3>
<h4 align="center">Definitely some Windows file format</h4>
<p><strong>From Elizabeth Sedgwick
</strong></p>
<p align="right"><strong>Answered By Mike Orr, Heather Stern, Don Marti
<br></strong></p>
<p><strong>
Gees, I hope you can help me.
</strong></p>
<p><strong>
I just loaded PaperPort software for windows, which is used
with a scanner for photographs, etc. onto my computer. The
extension for the software is .max. When I send photographs
to friends, they can<61>t open them. Do they have to have the
software on their computer to open the files?
</strong></p>
<p><strong>
In trying to solve this problem, I saved the photos with a
.jpeg extension and am sending them this way. Some of my
friends do not have .jpeg type software in their computers.
Is there some way to download jpeg software from the
internet if you don<6F>t have it on your computer?
</strong></p>
<p><strong>
Your help with be so appreciated?
Elizabeth
</strong></p>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
This is Linux Gazette, not Windows Gazette. You'd get a better
answer by asking a Windows group.
</BLOCKQUOTE>
<BLOCKQUOTE>
.max is not a normal image extension like .jpg, .gif, .png. It
is very likely the recipient does not have a .max reader installed.
Nowadays they probably DO have a .jpg viewer of some sort
already installed. How to view the image depends totally on the
recipient's mail program and other software. At worst, they can save
the .jpg's as files and view them in Netscape or Internet Explorer using
a URL like file:/directory/filename.jpg . (May need "\" or "\\"
and a "c:" prefix under Windows?)
</BLOCKQUOTE>
<BLOCKQUOTE>
IF they are running Windows, it's possible something called "File
Associations" has a bad configuration. This is a table that tells
Windows which program to use to open a .jpg or .jpeg file when you
double-click it. In Win95, it was a setting in Windows Explorer off one
of the menus somewhere. In Win98/2000, I have no idea where it is.
</BLOCKQUOTE>
<p><em>... Great help, but Elizabeth is confused ...</em></p>
<P><STRONG><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Thank you for your help.
</strong></p>
<p><strong>
When I transmitted my email, it was sent to <A HREF="mailto:linux-questions-only@ssc.com"
>linux-questions-only@ssc.com</A>. How it
reached you is beyond me.
</strong></p>
<p><strong>
Thanks for your ideas!! You're right about jpeg.
</strong></p>
<p><strong>
For your info, I learned that jpeg software comes with Microsoft Explorer.
I tried it, and the photos were highly enlarged at the receiver's end. It
worked, but you had to look through several screens to see the whole photo.
The photo was smaller than screen size when I sent it.
</strong></p>
<p><strong>
I did find a solution that seems to work. I use the extension of .exe and
people are able to open the file without special software.
</strong></p>
<p><strong>
Thanks again!!!
</strong></p>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
<A HREF="mailto:linux-questions-only@ssc.com"
>linux-questions-only@ssc.com</A> was originally an alias for Jim Dennis, who answered the
questions and collected the threads to publish in Linux Gazette.
To ease the burden on him, we expanded it to The Answer Gang
(<A HREF="mailto:linux-questions-only@ssc.com"
>linux-questions-only@ssc.com</A>), a mailing list with about ten subscribers. All of them
see the questions and try to respond. This also improves the quality of
the answers.
</BLOCKQUOTE>
<p><em>... Elizabeth is right to wonder ...</em></p>
<P><STRONG><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Does <A HREF="mailto:linux-questions-only@ssc.com"
>linux-questions-only@ssc.com</A> answer questions about windows?
</strong></p>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
No. Sometimes we will anyway, but generally not.
</BLOCKQUOTE>
<BLOCKQUOTE>
I used to do Windows support at a hospital, so I remember the tricks
I used then. But I haven't used Windows hardly at all since 1998.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Don]
About Windows/Linux interoperability, yes. If there's no Linux in
the picture at all, then no.
</BLOCKQUOTE>
<BLOCKQUOTE><em>
Any technology distinguishable from magic is insufficiently advanced.
</em></BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
We actually try to answer questions, but only have any interest in
answering Linux questions. There are lots of sites dedicated to Windows.
</BLOCKQUOTE>
<BLOCKQUOTE>
Perhaps a better question would be, if one of the Gang feels inclined to
answer a Windows question anyway, do we publish it? Usually not. If it
involves interoperability, or it looks like Linux users
might also somehow benefit from the answer, or it gives our crew an
opportunity to advocate Linux a bit, then we do.
</BLOCKQUOTE>
<p><em>... Fair enough, but then ...</em></p>
<P><STRONG><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Thank you for corresponding with me. Is there another web location I can
contact to obtain answers to Windows questions?
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Not that I know of in particular. There are USENET newsgroups
(comp.os.ms-windows.* I think), which you can access at
<a href="http://www.deja.com/">www.deja.com</a>.
</BLOCKQUOTE>
<BLOCKQUOTE>
Or go to Google (<A HREF="http://www.google.com"
>http://www.google.com</A>) and type some keywords.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
There's a tips area at <a href="http://www.winfiles.com">winfiles.com</a>,
but it's nothing like we have. Here is a real nice opportunity for one of
the Windows related magazines to do a Windows Answers column like ours on
their website...
</BLOCKQUOTE>
<!-- end 11 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/12"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 12 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Help Me Delete Linux</H3>
<p><strong>From Antony
</strong></p>
<p align="right"><strong>Answered By Mike Orr
<br></strong></p>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Hi, I recently attempted to install Linux Mandrake, but I did it wrong and know Windows has been
deleted and linux won't work, all I want to do is Delete linux so I can reinstall Windows and be
happy again, I cant even install windows at the moment because linux is taking up too much room on
the hard drive. Mum is heaps annoyed as she can't use the computer so can you please help me
quickly? Thanks
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Hmm, three questions about uninstalling Linux in two days. I wonder what
that means.
</BLOCKQUOTE>
<BLOCKQUOTE>
Doesn't the Windows setup program allow you to repartition your disk as
part of the process? If not, that's a big omission.
</BLOCKQUOTE>
<BLOCKQUOTE>
Anybody here use Mandrake? Does it come with a boot floppy that can be
used as a rescue disk? If so, you should be able to boot from the floppy,
press Alt-F2 to go to the second virtual console, run "cfdisk" or "fdisk"
and delete the Linux partitions (or all the partitions), and then reboot
and run the Windows install program.
</BLOCKQUOTE>
<!-- end 12 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/19"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 19 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Removing Linux: Sacrilege!</H3>
<H4 ALIGN="center">or: <TT>/bin/dd</TT> is your friend!</H4>
<p><strong>From Kevin Gray
</strong></p>
<p align="right"><strong>Answered By Mike Orr, Jim Dennis
<br></strong></p>
<!-- ::
Removing Linux: Sacrilege!
~~~~~~~~~~~~~~~~~~~~~~~~~~
or: <TT>/bin/dd</TT> is your friend!
:: -->
<P><STRONG>
hello i was just wondering how to remove linux from my system. I have two
hard drives one with linux and the other with windows 98. Everything works
fine but I just never use linux and since I don't have the time or technical
know how as to operate linux i would like to get my hard drive back. Is
there a way to do this? Any help would be appreciated. Thank you.
</STRONG></P>
<P><STRONG>
Until your next letter I remain,
<br>Sincerely Yours,
<br>Kevin Gray
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Is Linux on your primary drive or second drive? If it's on your second
drive, use Windows fdisk program to delete the Linux partitions and
create DOS partition(s). If you can't find a graphical fdisk program
under the start menu, open a DOS box and type "fdisk". Choose the
option to switch drives if necessary), then the option to print
partition information. Verify which are the Linux partition(s) and
delete them. Then either make one big DOS partition or several small
ones. Close and reboot, open My Computer, right-click on each new
partition and choose "Format" from the menu.
</BLOCKQUOTE>
<BLOCKQUOTE>
If Linux is on your primary drive, can you switch the drive cables
and/or jumpers to make Windows the primary drive? Be warned that
Windows programs tend to go into convulsions if you change drive letters on
them. Windows assigns drive letters according to which partitions it
finds first, so moving drives around or changing DOS partitions changes
the drive letters. Use the Windows utility to make a rescue floppy
first.
</BLOCKQUOTE>
<BLOCKQUOTE>
If you're using LILO to boot, you can eliminate it by using
"<TT>fdisk /mbr</TT>", an undocumented option to Windows' fdisk program. This
replaces the master boot record on the disk with Windows' default
version. Note that Windows' boot loader is primitive: it won't
give you a menu, it'll just boot whichever primary partition is active
(on the first disk only). You must first make that partition active
(=bootable) using fdisk, and ensure ONLY ONE partition is active.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
Note that most versions of MS FDISK will refuse to remove
non-MS-DOS partitions. You can use Linux fdisk to remove partitions
or you can use dd to complete wipe out all data on the Linux
disk which will make it look like it's fresh from the factory
so far as MS is concerned.
</BLOCKQUOTE>
<BLOCKQUOTE>
Also note that swapping drive letters out from under a MS OS
installation is basically guaranteed to hurt worse than backing
up your data to floppies, re-installing the OS from scratch,
re-installing all applications and restore copies of your data
into place. (This re-installation process has the added benefit
of ensure that you have backups and of cleaning out all of the
cruft that tends to accumulate in Microsoft based operating
systems over time).
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
When I use it, it just asks, "Delete non-DOS partition?" and does
it.
</BLOCKQUOTE>
<BLOCKQUOTE>
You can use Linux fdisk to delete the partition, but be careful,
because then Linux won't exist but will still be running. Do it
in single-user mode (type "linux single" at the LILO prompt),
then reboot immediately after exiting the program. Even better
would be to boot from a Linux rescue floppy (which probably came
with your distribution) so that you're not deleting the
currently-running system.
</BLOCKQUOTE>
<p><em>... and the real nitty gritty instructions ...</em></p>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
Let's assume that you have two IDE drives and that you have
Linux installed on what MS-DOS/MS Windows would call your "D:"
drive (<TT>/dev/hdb</TT> or <TT>/dev/hdc</TT> or even possibly <TT>/dev/hdd</TT> under Linux).
Obviously that could be <TT>/dev/sda</TT> if you're using a combination of IDE
and SCSI or <TT>/dev/sdb</TT> if you have two SCSI drives.
</BLOCKQUOTE>
<BLOCKQUOTE>
So, let's assume that MS Windows is installed on <TT>/dev/hda</TT> and
that Linux is on <TT>/dev/hdc</TT> (perhaps your CD-ROM drive is <TT>/dev/hdb</TT>
<TT>/dev/hdd</TT>).
</BLOCKQUOTE>
<BLOCKQUOTE>
To remove Linux as though it had NEVER been there you can follow
these steps:
</BLOCKQUOTE>
<blockquote><pre> lilo -u /dev/hda
</pre></blockquote>
<BLOCKQUOTE>
... should attempt to copy <TT>/boot/boot.0300</TT> back into <TT>/dev/hda</TT>
(that should have been the backup copy of your original master
boot record --- MBR). If that does work then prepare an MS-DOS
boot floppy (ask Microsoft how to do that with newer versions
of Win'9x; they'll swear that Win'9x isn't really DOS anymore,
but they're lying, of course).
</BLOCKQUOTE>
<BLOCKQUOTE>
Now to wipe out EVERYTHING from <TT>/dev/hdc.</TT>
</BLOCKQUOTE>
<font color="#990000">
<hr width="20%" align="center">
<BLOCKQUOTE>
WARNING!!!
</BLOCKQUOTE>
<BLOCKQUOTE>
The following will irrevocably wipe out all data
on a hard drive! Mistyping it can wipe out everything
on the wrong drive! IF YOU CARE ABOUT ANY OF YOUR
DATA, BACK IT UP! MAKE COPIES DON'T AND DON'T COME
CRYING TO US IF YOU FLUB THIS UP!!!!
</BLOCKQUOTE>
<BLOCKQUOTE>
WARNING!!!
</BLOCKQUOTE>
<hr width="20%" align="center">
</font>
<blockquote><pre> dd if=/dev/zero of=/dev/hdc bs=1024k # DANGER! Will Robinson!
</pre></blockquote>
<BLOCKQUOTE>
... this will scribble streams of ASCII "zeroes" (NUL characters) all
over <TT>/dev/hdc</TT> --- wiping out Linux.
</BLOCKQUOTE>
<BLOCKQUOTE>
When you reboot Linux will be gone (the kernel and the dd program
were in memory, but that's cleaned up on a system reboot).
</BLOCKQUOTE>
<BLOCKQUOTE>
If your system doesn't boot from its hard drive after this, then
pull out that MS-DOS boot floppy. By the way, you should have one
of those around for various recovery reasons --- it is a vital
part of running MS-DOS and recovery from any virus that your system
catches. Then run:
</BLOCKQUOTE>
<blockquote><pre> FDISK /MBR
</pre></blockquote>
<BLOCKQUOTE>
(That's a DOS command that should create a new boot record for
you).
</BLOCKQUOTE>
<BLOCKQUOTE>
If it still doesn't come up after this than refer to the huge
WARNING that precedes this dangerous command example. Sigh,
re-install MS-Windows and restore from backup.
</BLOCKQUOTE>
<!-- end 19 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/32"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 32 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Another uninstall: Getting to a Root Prompt to Blow it All Away</H3>
<p><strong>From Lynn Johnson
</strong></p>
<p align="right"><strong>Answered By Jim Dennis
<br></strong></p>
<!-- ::
Another uninstall: Getting to a Root Prompt to Blow it All Away
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
:: -->
<P><STRONG>
I am trying to remove linux - i logged in as root but where do I
type fdisk? I don't see a place to type anything - pls help -
thanks, lynn
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
I'm going to guess that you're logging through some graphical
service (xdm, kdm, gdm, etc). That would be the most common case
where you could log in as root and not see a text console and a
shell prompt.
</BLOCKQUOTE>
<BLOCKQUOTE>
So, assuming that this is the case the question becomes:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQuote>
How do I get to a root shell prompt?
</BLOCKQuote></BLOCKQUOTE>
<BLOCKQUOTE>
There are many possibilities. X can be configured to run any
of a number of GUIs (graphical user interfaces) such as <A HREF="http://www.kde.org/">KDE</A>,
<A HREF="http://www.gnome.org/">GNOME</A>, twm, fvwm, etc. Any of those can be configured to offer
a very limited number of menus (possibly no menus at all).
</BLOCKQUOTE>
<BLOCKQUOTE>
Typically you access your GUI's menus under X by clicking on the
"wall paper" (or screen "background" which is technically called the
"root window" in X parlance). That will bring up the "root menu."
(The windows and menus in X are thought of as a tree, just as your
filesystems are trees of directories, and subdirectories (branches)
and files (leaves). You might have to click with your right or
middle mouse buttons. That is configurable in most X window managers.
There might even be different menus that come up for each mouse
button. Typically one set of them would be the main set of menu
options and the other(s) would contain some special window manager
features to resize, raise, lower, move and destroy windows, select
"minimized" or "hidden" applications etc.
</BLOCKQUOTE>
<BLOCKQUOTE>
When you find the main menu tree you can search it for some entry
such as "xterm" or "rxvt" or "eterm" or "kterm" or for entries
that are referred to as "shells." Since X is completely configurable
the labels on the menus can be <EM>anything</EM>.
</BLOCKQUOTE>
<BLOCKQUOTE>
All of that aside it's probably easiest to skip all of this GUI
rigamarole. There are a couple of ways to do this. On most
systems you could switch away from X (and/or any of the display
managers -- the various graphical login tools) using the following
keystrokes:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQuote>
[Ctrl]+[Alt]+[F1]
</BLOCKQuote></BLOCKQUOTE>
<BLOCKQUOTE>
(That's holding down the "control" and the "alt" keys and typing
in the first function key). That should bring you to a text mode
login console (which is a virtual terminal/console running any of
the "getty" programs, usually mingetty under Linux.
</BLOCKQUOTE>
<BLOCKQUOTE>
From there you can log in as root and you should be presented with
a shell prompt (usually ending in a "#" hash/pound sign which
conventionally indicates a root prompt).
</BLOCKQUOTE>
<BLOCKQUOTE>
If that fails then you'll probably want to "break in" by rebooting.
It's possible for someone to configure a Linux box such that
there are no getty's running on any virtual consoles. It's even
possible to configure one to run multiple different X sessions
concurrently. I have a workstation at my new office which is
running four different xdm sessions.
</BLOCKQUOTE>
<BLOCKQUOTE>
So, if you system has been configured to remove the text
virtual consoles, or if you're running a distribution that only
makes a GUI available by default, then you'll want to reboot.
</BLOCKQUOTE>
<BLOCKQUOTE>
The easiest way to reboot from a graphical session under Linux
is to type:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQuote>
[Ctrl]+[Alt]+[Backspace], [Ctrl]+[Alt]+[Del]
</BLOCKQuote></BLOCKQUOTE>
<BLOCKQUOTE>
...in rapid succession. The first keystroke combination will
kill the X server, the other one will signal init (the process
manager under Linux) to perform a reboot.
</BLOCKQUOTE>
<BLOCKQUOTE>
Of course either of these features <EM>might</EM> also be disabled!
If that's the case then just hit the reset button on your
system, or flip the power switch (wait about 30 seconds and
turn it back on) or pull the power plug.
</BLOCKQUOTE>
<BLOCKQUOTE>
While it's booting wait for the keyboard lights to flash a
couple of times (while the system counts its memory, checks
it's floppies, etc). There will <EM>probably</EM> be a LILO prompt
(possibly this will be quite brief. So, as soon as you see
the keyboard caps lock, scroll lock, and num lock lights
flicker, turn on the caps and/or scroll lock. If they flick
back off in a second, turn them back on and hold down any
shift or control key.
</BLOCKQUOTE>
<BLOCKQUOTE>
All of these shenanigans are intended to interrupt LILO
(the most popular Linux loader) and convince it to give you
a prompt. At that prompt type:
</BLOCKQUOTE>
<blockquote><pre> linux init=/bin/sh rw
</pre></blockquote>
<BLOCKQUOTE>
Actually you might have to replace the first word in that
line with something else. What else? That depends. LILO
can be configured to call the Linux installations or "stanzas"
by any name you'd like. Also LILO can be configured not
to allow any interruption or it can be configured to require a
password to boot or to bypass the normal boot procedure.
</BLOCKQUOTE>
<BLOCKQUOTE>
However, more than 99% of all the Linux boxes in the world
today will give you a root prompt if you follow this last
procedure. There are only a few freaks like me that know enough
about Linux to configure LILO with passwords and/or to ignore
all attempts to get at a LILO prompt. (Of course there are
other boot managers for Linux. In particular newer versions
of Mandrake might use GRUB --- the grand unified bootloader;
and I haven't studied that one at all.
</BLOCKQUOTE>
<BLOCKQUOTE>
In the <EM>highly</EM> unlikely event that you <EM>still</EM> can't get at
a root prompt then you'll want to boot from a floppy or a
CD (such as the <A HREF="http://www.linuxcare.com/">Linuxcare</A> bootable business card or one of
its clones). I'm not going to go into the details on that
for right now. If you need to know how to do that just
search Google! (<A HREF="http://www.google.com/linux"
>http://www.google.com/linux</A>) for "recovery
disk" or go to Tom Oehser's site and read about Tom's
"root/boot" disk images (<A HREF="http://www.toms.net/rb"
>http://www.toms.net/rb</A>).
</BLOCKQUOTE>
<BLOCKQUOTE>
Notice that most of the difficulty here is that I have
no idea how your Linux system is configured, nor do I have
any idea what distribution you're running. As you might have
guessed from this long set of directions Linux is a bit
configurable.
</BLOCKQUOTE>
<BLOCKQUOTE>
Obviously once you get to a root prompt you can just
use the command:
</BLOCKQUOTE>
<blockquote><pre> fdisk /dev/hda
</pre></blockquote>
<BLOCKQUOTE>
... to work on the partitions on your primary IDE drive.
(You can use <TT>/dev/hdb</TT> for the secondardy IDE on the first
controller, <TT>/dev/hdc</TT> for the primary drive on the secondary
controller, etc; and you can use <TT>/dev/sda</TT>, <TT>/dev/sdb</TT>, etc
if you're using SCSI drives).
</BLOCKQUOTE>
<!-- end 32 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/13"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 13 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>setting root password</H3>
<p><strong>From Tom Weingarten
</strong></p>
<p align="right"><strong>Answered By Ben Okopnik
<br></strong></p>
<P><STRONG>
I've managed to work myself into quite the dilemma. Somehow my root
password has been deleted, so I can no longer enter my system except by
a second login, which does not have write permissions on anything or the
ability to acces linuxconf or userconf. I'm using RedHat Linux on a
dual-pentium box. However, I've found that the RedHat cd is far from
adequate for rescue purposes, so I created a mandrake cd, and can use it
to edit files. What do you suggest I do? Thanks in advance for your time
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
I've found that the RedHat CD (or boot floppy) actually works reasonably
well as a rescue disk - flipping to the 2nd console via "Alt-F2" and
mounting the existing hard drive is the answer (RedHat tech support told me
it couldn't be done and I should reinstall. &lt;sigh&gt
<IMG SRC="../gx/dennis/smily.gif" ALT=";)"
height="24" width="20" align="middle"> Whichever you choose,
fixing the root password problem is pretty easy - and before anybody starts
storming about it being a HUGE security hole, remember that "physical
access=root access". Period. It's the reason that locked server closets and
machine rooms exist. If you want just that tiny bit of extra security (your
eight-year-old computer genius has been trying random passwords against
"root" or some such), disable the floppy/CD boot and password the BIOS
(write your hard drive's cylinder/head/sector info on the side of the PC
case and *don't* lose <EM>that</EM> password; resetting the BIOS can be a touchy
business.)
</BLOCKQUOTE>
<BLOCKQUOTE>
So - boot your machine via a boot disk or CD. Mount the offending drive -
for this example, we'll say you have it under "<TT>/mnt</TT>". Edit
"<TT>/mnt/etc/passwd</TT>" (or "<TT>/mnt/etc/shadow</TT>" if you use shadow passwords) and
clear out the second field in the "root" entry (fields are separated by
colons) - that's the encrypted password. In other words, given an entry
that looks like this:
</BLOCKQUOTE>
<blockquote><pre>root:2St5fADe4oOcSE:0:0:root:/root:/bin/bash
</pre></blockquote>
<BLOCKQUOTE>
you should end up with this:
</BLOCKQUOTE>
<blockquote><pre>root::0:0:root:/root:/bin/bash
</pre></blockquote>
<BLOCKQUOTE>
Save the file and reboot, this time without the boot disk. Log in as root (no
password necessary) and immediately assign one using the "passwd" utility.
No muss, no fuss, no greasy aftertaste. And, umm, keep a close watch on
Junior: he might be reading this too...
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</BLOCKQUOTE>
<p><em>... Ben's a hero! ...</em></p>
<p><strong>
<img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Thanks a million. You've saved me the fate of hundreds of users asking what the
heck happened to their character files (I run an online game). Also, btw, while
searching desperately for a solution, I found that if you edit <TT>/etc/pam.d/login</TT>
and change everything to optional, you can login as root with the wrong
password. Then you can change the password, all from the boot cd. Although, your
method is infinitely simpler.
<IMG SRC="../gx/dennis/smily.gif" ALT=":-)"
height="24" width="20" align="middle">
</strong></p>
<p><strong>
Thanks again for your help.
Tom
</strong></p>
<!-- end 13 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/14"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 14 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>I can't seem to write to my vfat (Windoze) file system with any user other than root.</H3>
<p><strong>From John Fox
</strong></p>
<p align="right"><strong>Answered By Ben Okopnik
<br></strong></p>
<P><STRONG>
I currently run Red hat 7.0 and am attempting to follow the suggested
procedures of not logging on as root unless I absolutely have to. When I am
logged in to the system as my non-root user id, I am unable to write files
to the vfat file system.
</STRONG></P>
<P><STRONG>
I have tried to chown the mount point, I have even gone so far as to try to
chown and change the file permissions of a file on the vfat file system(to
no avail). I have checked the mount and all the vfat mounts all show (rw).
</STRONG></P>
<P><STRONG>
The following is the error message I receive when I attempt to copy a file:
cp: cannot create regular file `filename.ext': permission denied.
</STRONG></P>
<P><STRONG>
Does anyone have any idea?
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Yep; I remember cursing and scratching my head over this one quite a while
ago. You've got the right idea in looking at the permissions/ownership of
the mount point - but as you've found out, you can't just change them.
</BLOCKQUOTE>
<BLOCKQUOTE>
Here's the solution that I've used. I like this one, since it would work
well on a multiuser system as well as a regular home system. First, create
a group called "msdos". Note its GID (the number associated with that
group; take a look with 'vigr'.) Add yourself to that group -
</BLOCKQUOTE>
<blockquote><pre>adduser jfox msdos
</pre></blockquote>
<BLOCKQUOTE>
(assuming your username is 'jfox'.) Now, in your '<TT>/etc/fstab</TT>', add the
"noexec", "umask" and "gid" parameters to the appropriate partition:
</BLOCKQUOTE>
<blockquote><pre>/dev/hda3 /mnt/msdos vfat noexec,umask=003,gid=1001 0 0
</pre></blockquote>
<BLOCKQUOTE>
Obviously, the GID would be that of the "msdos" group.
</BLOCKQUOTE>
<BLOCKQUOTE>
What we're doing here is mounting that partition with the appropriate group
ID and setting the umask - this masks <EM>out</EM> the permissions that the
mounted partition will have. The "noexec" parameter works with in concert
with the other two to produce the following conditions:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQuote>
Directory access under the mountpoint is allowed to members of GID 1001
All files under the mountpoint are readable <EM>and</EM> writable by GID 1001
The files are "read-only" to the other users
None of the files are executable (does not apply to DOS emulation)
</BLOCKQuote></BLOCKQUOTE>
<BLOCKQUOTE>
It takes a bit to get used to this three-parameter control system, but
it is actually very flexible and can be used to set up just about any
combination of permissions and directory accessibility you could want.
</BLOCKQUOTE>
<BLOCKQUOTE>
From this point on, if you want to give a user on your system read/write
access to the files on that partition, simply add them to the "msdos"
group.
</BLOCKQUOTE>
<p><em>... wishing the docs were better ...</em></p>
<P><STRONG>
<img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Ben,
</STRONG></P>
<P><STRONG>
Thanks for your help. That did the trick. I think they could have made it
easier by putting somthing in the faq. On their site.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
You're welcome - glad I could help! Just as an idea, if you perceive this
as a topic that lacks coverage in the Linux community, consider writing a
HOWTO - the Linux Documentation Project, under whose auspices the LG
operates, is always on the lookout for more useful info that can be shared.
It's yet another way to put something back in as a return for the effort
that other Linux folks have put out - and this kind of feedback is
precisely what allows a community to grow.
</BLOCKQUOTE>
<p><em>... you can do it John! ...</em></p>
<p><strong>
<img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Will do Ben,
</strong></p>
<p><strong>
I would be happy to contribute to the community. I thought you had to be
hooked up with the right people in order to contribute. I will seriously
consider writing something up. Especially considering that I am on Vacation
until the end of the year and will have plenty of free time on my hands.
</strong></p>
<!-- end 14 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/15"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 15 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Firewall for a SOHO</H3>
<H4 ALIGN="center">Small World, isn't it?</H4>
<p><strong>From Tom Bynum
</strong></p>
<p align="right"><strong>Answered By Jim Dennis
<br></strong></p>
<!-- ::
Firewall for a SOHO
~~~~~~~~~~~~~~~~~~~~~~
Small World, isn't it?
:: -->
<P><STRONG>
Actually, hello from your mom's next door neighbor (...well....two
doors...damn it...close enough...). Anyway, I was talking with her out in
the cul-de-sac Sunday evening and she lent me her copy of your book to
browse.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
Mom mentioned that she'd been chatting with you.
</BLOCKQUOTE>
<blockquote>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Jim wrote a book?
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
Yeah, Linux System Administration by
<a href="http://www.newriders.com">New Riders Publishing</a>.
purple edge stripe,
"landmark" series with a view of the French river (the Seine I think) on the
cover's top quarter stripe.
</BLOCKQUOTE>
<BLOCKQUOTE>
Wherein the first half describes policies so real decisions can be made, and
the second half describes practicum, so sysadmins can Do Cool Stuff. eg. to
have an awk script "vette" the logs of all the boring ordinary stuff amd leave
you the stuff that looks new or weird.
</BLOCKQUOTE>
<BLOCKQUOTE>
It's a good thing
<IMG SRC="../gx/dennis/smily.gif" ALT=":&gt;"
height="24" width="20" align="middle">
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
That's cool that
New Riders has a Linux book. Several of us at SSC have been very impressed
with the two New Riders' books on Python and PHP, so I'll have to take a look
at this one. The other two books are very concise: they give you a lot of
information in a small space, and answer questions you didn't think to ask,
more so than books three times their size.
</BLOCKQUOTE>
</blockquote>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
I spend about 99.8% of my time in Windoze.......(snore.....) so please
forgive some rather newbie questions, but I have an idea that incorporates
Linux in a big way.
</STRONG></P>
<P><STRONG>
Let me give you a short Linux bio...
I was first exposed to Linux back in 1997 when someone at my ISP mentioned
using it for an internal mail server. I figured "...how hard can it be..".
I went and bought a book which included 3 distros. I ended up using <A HREF="http://www.caldera.com/">Caldera</A>
Openlinux Lite 1.0. (because it was the only one that would install) In
about a week I got Sendmail to work with the ISP through a dial-up SLIP/PPP
connection. At that time we only had a single company dial-up account so I
had the machine using a crontab to dial-up and kick the SMTP server every 3
hours or so. The "kicking" part was something I found to make SMTP work
through a dynamic dial-up account. Later I installed ISDN and a router and
got a static IP so we were live and just had to turn off the crontab. I got
burned on "relaying" with that server and didn't know how to turn it off so
I installed Caldera OpenLinux 2.3 because it contained the new distribution
of Sendmail with relaying blocked out-of-the-box.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
Yes. Sendmail has a near vertical learning curve (and qmail is even
more confusing for me). I actually like Postfix (now that I've tried it)
but I'm NOT recommending that you switch to a new MTA (mail transport
agent). You got something that works well enough. You've learned enough
to get by; and if you need to hire a consultant than there are LOTS of
them that know sendmail and very few who understand the corresponding
intricacies of qmail, Postfix, exim or any other MTA.
</BLOCKQUOTE>
<BLOCKQUOTE>
There is a really cool option to consider. You could buy the commercial
sendmail package and use it's little configuration system. You'd still
be running the same sendmail that you are now; but you'd have a somewhat
less gruesome interface for doing the basic configuration. (If you later
had really special needs you could have someone start with those basic
configuration files.
</BLOCKQUOTE>
<BLOCKQUOTE>
Look at <A HREF="http://www.sendmail.com"
>http://www.sendmail.com</A> for information on pricing and all of
that.
</BLOCKQUOTE>
<BLOCKQUOTE>
As for setting the "maximum message size" limit: you should be able
to edit your <TT>.../sendmail.cf</TT> file (either in <TT>/etc/</TT> or in <TT>/etc/mail/</TT>
depending on your distribution) and find a line that looks something
like:
</BLOCKQUOTE>
<blockquote><pre>#O MaxMessageSize=1000000
</pre></blockquote>
<BLOCKQUOTE>
... to make that work just remove that first character (the '#' or
hash sign) which "uncomments" that line. The value is in characters
or octets (I'm not really sure which --- but they are the same for
ASCII and I doubt that you're getting alot of Unicode or UTF8 traffic
yet).
</BLOCKQUOTE>
<BLOCKQUOTE>
If you don't find this line then insert it somewhere in the
first section of the .cf file. That means to put it before the
first line that starts with a P (which looks like the following
line in one of my sendmail.cf files):
</BLOCKQUOTE>
<blockquote><pre>Pfirst-class=0
</pre></blockquote>
<BLOCKQUOTE>
Sendmail isn't terribly picky about what order the options
appear in, but it can be picky about which "section" they're
in. (In other words the options should all be grouped together
near the top of the cf file, the re-writing rules should all
be grouped together near the end of the file.
</BLOCKQUOTE>
<BLOCKQUOTE>
Note: It's better if you're using a macro config file (usually
named &lt;something&gt;.mc). So, here's a simple sample .mc file
showing a valid confMAX_MESSAGE_SIZE definition:
</BLOCKQUOTE>
<blockquote><pre>divert(-1)
# After the `divert(0)' all lines starting with `dnl' are
# comments until the next newline character.
include(`/usr/share/sendmail/m4/cf.m4')
divert(0)dnl
VERSIONID(`Linux Dec 19 16:43:03 PST 2000')
OSTYPE(`linux')dnl
dnl
define(`confMAX_MESSAGE_SIZE', `1234567890')dnl
define(`confPRIVACY_FLAGS', `authwarnings,novrfy,noexpn')dnl
define(`LUSER_RELAY', `local:postmaster')dnl
FEATURE(`nocanonify')dnl
FEATURE(use_cw_file)dnl
FEATURE(`always_add_domain')dnl
MASQUERADE_AS(`PUT_YOUR_DOMAIN_HERE')dnl
FEATURE(`masquerade_envelope')dnl
FEATURE(`allmasquerade')dnl
MAILER(`local')dnl
MAILER(`procmail')dnl
MAILER(`smtp')dnl
MAILER(`uucp')dnl
MAILER(`bsmtp')dnl
MAILER(`fido')dnl
dnl
LOCAL_CONFIG
</pre></blockquote>
<BLOCKQUOTE>
Most of represents a typical sendmail .mc file. In order to
use this to generate a .cf file (which is what sendmail uses)
we issue a command like:
</BLOCKQUOTE>
<blockquote><pre> m4 &lt; $THIS_MC_FILE_NAME &gt; /etc/sendmail.cf
</pre></blockquote>
<BLOCKQUOTE>
(Note: DON'T DO THIS using the sample I've given. You'll
wipe out your existing sendmail.cf file!)
</BLOCKQUOTE>
<BLOCKQUOTE>
The idea here is not really that complicated. sendmail uses
the cf file which is in a format that's convenient for the program.
For years people maintained cf files directly (using a text editor).
For some of us (myself included) it is still easier to make a small
change to an existing .cf file then it is figure out the corresponding
.mc file directive.
</BLOCKQUOTE>
<BLOCKQUOTE>
However, most of the text in the .cf file looks like line noise.
So mere mortals among us prefer to create shorter files that summarize
what we want sendmail to do. Then we pass these shorter .mc files
through a macro expansion tool (the m4 program) and they get expanded
into the .cf files that sendmail uses.
</BLOCKQUOTE>
<BLOCKQUOTE>
But enough about sendmail. On to your question.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
"Whew"...all right, here I am today. The box runs, I don't screw with it.
Every now and then some bozo over in drafting tries to stuff a CAD drawing
in an email message, but after a little staff chastising and a re-boot,
everything's back to normal. BTW, I've seen that "max message size" line in
the sendmail.cf, but everytime I try and make the line active, the server
issues an error when booting the sendmail daemon so I had to rem it out
again...sorry, back to my point...
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
(See above)
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
I want to set up a Linux box to implement Firewall and Proxy services. For
you that might be straight forward, but all the information I find is
sending me in mental circles...
</STRONG></P>
<P><STRONG>
This is what we currently have setup...Static address from ISP <TT>--&gt;</TT> Router
(with ISDN modem) using NAT <TT>--&gt;</TT> Private address on the Lan side of the
router. DHCP running on the network tells all the clients that the router
address is the gateway. All works...thanks for shopping at Kmart. Not very
safe...
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
I like to use pictures when I'm designing networks.
</BLOCKQUOTE>
<BLOCKQUOTE>
It sounds like you have this:
</BLOCKQUOTE>
<blockquote><pre> * eth0
v
+---------+ +--------+ +-----+
| ISP |-----| Router |--+--| LAN |
+---------+ +--------+ | +-----+
^ |
* eth1 | +-----------+
+---| Linux Box |
+-----------+
</pre></blockquote>
<BLOCKQUOTE>
... but it's not clear. Clearly your Linux box cannot be
receiving mail from the Internet if it's using a "private"
(non-routable RFC1918) IP address. That is to say that you
can't advertise a 192.168.*.*, 10.*.*.* or 172.16.*.* through
172.31.*.* address to the Internet as your MX (mail exchanger).
If you did so, then no one would be able to route SMTP (or any
other IP traffic) to you.
</BLOCKQUOTE>
<BLOCKQUOTE>
However, it's possible that you could have a feature/rule on your
router such that it relayed any incoming traffic on TCP port 25
on eth1 (the outer interface) to the same port on your Linux box.
</BLOCKQUOTE>
<BLOCKQUOTE>
This is one way to put a "hidden" server behind a router. However,
it assumes that you have a router that is capable of doing such
relaying (or "transparent proxying"). There are a number of programs
capable of doing this for Linux.
</BLOCKQUOTE>
<BLOCKQUOTE>
(Another, less interesting and less useful solution would be for
your ISP to act as a your MX record AND for them to maintain their
own routes to your RFC1918 network. Of course then you'd have to
co-ordinate this with your ISP and they'd have to assign different
RFC1918 address blocks to each of their customers that wanted this
service, and you'd have to maintain split DNS, and ... anyway
forget I mentioned that).
</BLOCKQUOTE>
<BLOCKQUOTE>
Another option would be to use the Linux box <EM>as</EM> both the
router and the sendmail host. This is possible (so long as you
can connect your ISDN modem or TA to your Linux box).
</BLOCKQUOTE>
<BLOCKQUOTE>
Yet another option would be to have your ISP give you more than
one static IP address. Two would be sufficient; four would be a
relatively normal subnet, though only two would be usable in
that.
</BLOCKQUOTE>
<BLOCKQUOTE>
Note: most of these configurations are NOT recommended. They
offer little or no protection for the sendmail boxes, and
nothing protects your internal network from a potentially
compromised sendmail box.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Here's what I want. (It sounds safer....so I'm gonna try and draw you a
mental picture here so bear with me...)
</STRONG></P>
<P><STRONG>
Static address from ISP <TT>--&gt;</TT> Router (with ISDN modem) using NAT <TT>--&gt;</TT> Firewall
(eth1 on linux box) <TT>--&gt;</TT> Firewall/Proxy/NAT services running inside box <TT>--&gt;</TT>
Gateway (eth0 on linux box)--&gt; Network
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
It sounds like you're saying that you want something like:
</BLOCKQUOTE>
<blockquote><pre> +---------+ +--------+ +-----+
| ISP |-----| Router |----| LAN |
+---------+ +---+----+ +-----+
|
| +-----------+
+---| Linux Box |
+-----------+
</pre></blockquote>
<BLOCKQUOTE>
This is a reasonable configuration. You still need to
have some way of routing traffic to the Linux box. That can
still be a TCP relay utility or feature running on the router
and redirecting all inbound SMTP (TCP port 25) traffic to
the Linux mail host. It could be a different DRIP (directly
routable IP address) from your ISP.
</BLOCKQUOTE>
<BLOCKQUOTE>
It could even be a hack where all your incoming mail gets
stored by your ISP and is fetched into your domain via
POP or IMAP. (I suspect that this is the way you were doing
it when you were in dial-up. I suppose it might be what you're
still doing; it's not clear from your message). Another trick
is for your ISP to be your primary MX, and for them to relay
it to you via UUCP (over TCP).
</BLOCKQUOTE>
<BLOCKQUOTE>
I used to get my mail via UUCP, and that was only a couple
years ago.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Basically just insert it between the network and the router. Does that make
sense? Here's the reason for the router being on the end...it has my ISDN
modem built-in. It's the only device I have that can run the ISDN
connection. Things are too $tight$ to get a nice connection like a T1 with
expensive firewalls and such, so I'm trying to make this work cheap! I also
want the logging and auditing provided by the proxy.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
The problem here is getting the incoming traffic to your Linux
box. I'm guessing that you might have something like a Trancell Webramp
ISDN TA/router. You could replace that with an ISDN card or an external
ISDN "modem" (which connects to your Linux box via a serial port).
</BLOCKQUOTE>
<BLOCKQUOTE>
In those cases you'd have the routing and mail services running on
a single system (which is not a good security profile since a
compromise of your mail host constitutes a loss of control of
all of your routing).
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
The final effect is, a second "private" network between the linux box and
the router. So I will have one subnet for the LAN in general and eth0 of the
box on that side. A second private address space and "subnet" available
only between eth1 and the router, and then of course our static IP on the
outside. To me it kind of resembles a "DMZ" which most modern routers have
built in. Let's call it a poor man's "DMZ".
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
Oh you mean:
</BLOCKQUOTE>
<blockquote><pre> +---------+ +--------+ +-----+
| ISP |-----| Router | +-----| LAN |
+---------+ +---+----+ | +-----+
| |
| +-----------+ |
+---| Linux Box |-+
+-----------+
</pre></blockquote>
<BLOCKQUOTE>
... that's O.K. In this case Linux is acting as an interior
router (and as a mail host). Even better would be:
</BLOCKQUOTE>
<blockquote><pre> +---------+ +--------+ +-----+
| ISP |-----| Router | +-----| LAN |
+---------+ +---+----+ | +-----+
| |
| +--------------+ |
+---| Linux Router |-+
| +--------------+
|
| +-------------------+
+---| Linux Mail Server |
+-------------------+
</pre></blockquote>
<BLOCKQUOTE>
Where you use two different Linux boxes, one as a router and
the other as a mail server.
</BLOCKQUOTE>
<BLOCKQUOTE>
You'd still want your ISP to give you one or two more DRIP
addresses (for the exterior interface on your Linux box(es)).
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Does this sound off the wall? Every "how-to" I find for using Linux as a
firewall talks about it being the "router" at the end of the line between
the LAN/WAN. I haven't heard of it being used as I have described and I'm
really not sure where to go from here. It all sounds good on
paper..."...Client on the net ships a packet off to the gateway (eth0)...The
linux box runs it's firewall/proxy voodoo magic stuff and ships it out the
other side (eth1) to the router which of course really ships it out...".
But how about on the return trip? With the firewall and the router both
using NAT...the router won't care, but how about inside the linux box? Will
the packets still back and forth to each client OK?
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
Linux can be used as a border router and/or as an interior router.
</BLOCKQUOTE>
<BLOCKQUOTE>
An even better configuration would be:
</BLOCKQUOTE>
<blockquote><pre> +---------+ +--------+ +-----+
| ISP |-----| Router | +-----| LAN |
+---------+ +---+----+ | +-----+
| |
Note ---&gt; | +--------------+ |
+---| Linux Router |-+
+------+-------+
|
|
+------+-------+
| Linux Server |
+--------------+
</pre></blockquote>
<BLOCKQUOTE>
... where you have three ethernet interface in your Linux Router
(a three legged firewall).
</BLOCKQUOTE>
<BLOCKQUOTE>
Note: this could be an ether crossover cable between the ISDN
router and the Linux box, or it could be a serial connection
between the Linux box and an external ISDN modem/TA (terminal
adapter) or the whole thing could be replaced with an internal
ISDN card that's plugged into the Linux Router. (In that last
case, think of this line as being the Linux Router's internal
PCI or ISA bus).
</BLOCKQUOTE>
<BLOCKQUOTE>
The advantage here is that all traffic passes through the Linux
Router (where you can do packet filtering, IP redirection, logging).
However, if the Mail Server gets compromised then it can't be
easily used to attack the LAN machines. (The mail server is not
trusted by the LAN machines, it is only allowed to received outbound
mail, and POP or other mail fetching connections from ther internal
hosts.
</BLOCKQUOTE>
<BLOCKQUOTE>
You can also sequester other services on the Linux Server. You can
put a DNS server on it, etc. Note that each service that you run on
the Linux Server the greater the risk that one of those services can
be used as a whole through which an attacker can compromise that
machine. So, if you run mail, DNS, web and FTP all on that one
Linux server, then any exploit in any one of those can affect
the whole server, and thus compromise all of your DNS, mail, web,
and FTP services.
</BLOCKQUOTE>
<BLOCKQUOTE>
That's why we don't run those services on the router. On my
router at home, there are NO services running (not even ssh).
I cannot access it remotely. I must sit at the keyboard and work
from the console directly. In fact there are IP packet filtering
rules that prevent that system from accepting <EM>any</EM> packets that
are addressed to it. You can't even ping it! (It will only
permit traffic that is supposed to go <EM>through</EM> it, not <EM>to</EM> it).
</BLOCKQUOTE>
<BLOCKQUOTE>
You could hang as many seperate Linux servers off of this eth2
interface (DMZ network segment) as you like. However, you'll
either need to have separate real IP addresses (DRIPs) for each,
or you'll have to configure the Linux router to do TCP and UDP
redirection for each service to each server.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
I feel like a five year old asking why the sky is blue... I did find out one
thing this past weekend...IPchains works in here somewhere...that's about
all I know.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
Actually your question is reasonably sophisticated, and your
criticism of the HOWTOs is well taken.
</BLOCKQUOTE>
<BLOCKQUOTE>
The biggest issue here is that you have two different problems
to solve. First you need routing to work. You need more IP
addresses or you need to install some form of TCP/UDP redirect
utility. Keep in mind that the TCP/UDP redirect utilities might
be running as 'root' (if they are listening on "privileged" ports)
and, therefore might be a security risk <EM>on the router</EM>. There's a
way to use IPChains to redirect TCP traffic into a Unix domain socket
and I think there should be a utility to relay connections from
a Unix domain socket back to a TCP connection. However, I haven't
looked for one recently and I don't remember if there was one the
last time a question like this came up.
</BLOCKQUOTE>
<BLOCKQUOTE>
(The advantage of this approach would be that it would allow the
redirection utilities to run as "nobody", or (better yet) as a
set of mutually non-trusting "nobody" UIDs --- which minimizes
the risk to the router).
</BLOCKQUOTE>
<BLOCKQUOTE>
That's why the router in a firewall is called a "bastion." You
want it to be relatively simple with as few windows, doors as
possible and NO ornamentation.
</BLOCKQUOTE>
<BLOCKQUOTE>
I currently have a block of IP addresses, so I haven't had to
resort to incoming IP redirection. (Otherwise I'd tell you the
name of the utility that I was using).
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
I've said more than enough...time for a beer. Hope to hear from you soon.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
I agree. I'm off to BALUG (<A HREF="http://www.balug.org"
>http://www.balug.org</A>) where I'll fill up
on Tsing Tao and other chinese food.
</BLOCKQUOTE>
<!-- end 15 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/16"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 16 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Something comparable to Services in NT</H3>
<p><strong>From Michael Swanson
</strong></p>
<p align="right"><strong>Answered By Mike Orr
<br></strong></p>
<P><STRONG>
I've been playing with Linux for years, and just recently decided that I
wanted to learn more about it. At this point I feel as though I know
nothing. I have compiled and installed a proxy server in my Mandrake 7.1
system. But I have to log in as ROOT to run it. And I must run it everytime
I reboot. I would like to have this run at start everytime. As I
understand it, anything run at startup is root, and this program (squid) says
it changes user after initialization. The documentation mentions how the
program will respond after being automatically started, but gives no mention
at all on how to achieve this.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
See if Mandrake uses the System V init scheme like <A HREF="http://www.redhat.com/">Red Hat</A> and <A HREF="http://www.debian.org/">Debian</A>
do. You have one directory containing start/stop scripts, and other
directories containing symlinks to those scripts. On Debian (which I'm
familiar with), the script directory is <TT>/etc/init.d</TT>, and the normal
symlink directory is <TT>/etc/rc2.d</TT> . In that directory, put a link called
S##squid pointing to the script. (Replace "##" with a 2-digit number
indicating which order to run it--lower numbers get started first.)
Mandrake is probably the same but the directories may be named
slightly differently.
</BLOCKQUOTE>
<BLOCKQUOTE>
Look for a README in the script directory, <TT>/usr/doc/sysvinit</TT>,
"man init", etc. There's also a HOWTO "From Power Up to the Bash
Prompt"
(<A HREF="http://www.ssc.com/mirrors/LDP/HOWTO/From-PowerUp-To-Bash-Prompt-HOWTO.html"
>http://www.ssc.com/mirrors/LDP/HOWTO/From-PowerUp-To-Bash-Prompt-HOWTO.html</A>)
that explains everything that happens when the computer boots up;
this is worth looking through even just to know what info is available
in it.
</BLOCKQUOTE>
<!-- end 16 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/17"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 17 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Editing fstab file for tape backup</H3>
<p><strong>From Michael Dodge
</strong></p>
<p align="right"><strong>Answered By Mike Orr, Dan Wilder
<br></strong></p>
<P><STRONG>
Dear Answer Guy:
</STRONG></P>
<P><STRONG>
I have installed a tape drive onto a 586 intel. The tape drive is an HP
SCSI drive. I had someone that I know compile the Kernel to support SCSI,
but I wasn't able to mount the tape drive. I think that it is because I
haven't proplerly edited the fstab file.
</STRONG></P>
<P><STRONG>
I reads:
</STRONG></P>
<P><STRONG><BLOCKQuote>
<TT>/mnt/N</TT> tape
</BLOCKQuote></STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
I haven't actually used a tape drive, but I've never seen any that are
mountable in the way floppy disks are. So you don't need an entry in
fstab. (If you did, it would be
</BLOCKQUOTE>
<BLOCKQUOTE><pre>/dev/DEVICE /mnt/N FILESYSTEM_TYPE OPTIONS 0 0
</pre></BLOCKQUOTE>
<BLOCKQUOTE>
)
You would especially want the "noauto" option to prevent it from
automatically mounting the tape at boot time. (Which would cause an
unpleasant delay if there was no tape in the drive.)
</BLOCKQUOTE>
<BLOCKQUOTE>
But as I said, I doubt you can mount tapes at all anyway.
</BLOCKQUOTE>
<BLOCKQUOTE>
Normally, you must figure out which device it is, and then use that as
the "filename" argument to your backup program (e.g., tar). E.g.,
</BLOCKQUOTE>
<BLOCKQUOTE><pre>tar tvf /dev/rmt8 /home/me
</pre></BLOCKQUOTE>
<BLOCKQUOTE>
You use the "mt" command to skip forward or backward
over one or more tarfiles on the tape, rewind the tape, retension it, etc.
</BLOCKQUOTE>
<BLOCKQUOTE>
There is a ftape HOWTO. Although that's not the kind of tape drive you
have, section 7 ("Backing up and restoring data") may be of help.
</BLOCKQUOTE>
<p><em>... thanks, now to <strong>make</strong> the backup ...</em></p>
<P><STRONG>
<img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Tag,
</STRONG></P>
<P><STRONG>
Thanks for the advice. I have another question though. I use the tar
command to read from the tape, but how do I write to the tape. I would
greatly appreciate any advice on this matter. Thanks.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Dan]
To write to tape:
</BLOCKQUOTE>
<blockquote><pre> tar cf /dev/st0 files-to-tar
</pre></blockquote>
<BLOCKQUOTE>
To read from tape:
</BLOCKQUOTE>
<blockquote><pre> tar xf /dev/st0 files-to-tar
</pre></blockquote>
<BLOCKQUOTE>
"c" means "create" archive, "x" means "extract". In this case,
"<TT>/dev/st0</TT>" is your archive.
</BLOCKQUOTE>
<BLOCKQUOTE>
The answers to this and many other questions about "tar" are found
if you type
</BLOCKQUOTE>
<blockquote><pre> man tar
</pre></blockquote>
<p><em>... kudos gang! ...</em></p>
<P><STRONG>
<img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
I would like to thank Dan for the final piece of advice on this matter. You
have helped me solve a problem that I have been working on for some time. I
know that this stuff is probably cake for you guys at tag, but for someone
not as experienced with LINUX (myself for example), these tips really save
the day.
</STRONG></P>
<P><STRONG>
Sincerely,
<br>Mike Dodge
</STRONG></P>
<!-- end 17 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/18"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 18 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Mail gets nowhere?</H3>
<p><strong>From anonymous
</strong></p>
<p align="right"><strong>Answered By Mike Orr
<br></strong></p>
<P><STRONG>
Do I ask you what does it mean when I get permanent fatal errs for
</STRONG></P>
<pre><strong> MAILER-DAEMON@aol.com &lt;mailto:MAILER-DAEMON@aol.com&gt; transcript of session
follows while talking to yd.mx.aol.com
RCPT to:MAILER-DAEMON@aol.com &lt;mailto:MAILER-DAEMON@aol.com&gt;
&lt;&lt;550MAILER-DAEMON@aol.com &lt;mailto:550MAILER-DAEMON@aol.com&gt; &gt;...User
unknown
</strong></pre>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
"User unknown" really does mean user unknown. aol.com has no user
"MAILER-DAEMON".
</BLOCKQUOTE>
<BLOCKQUOTE>
If something comes "from" MAILER-DAEMON, it's an error message, probably
reporting a previously-failed message.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
If I am asking the wrong person please direct me to the appropriate person.
What prompt to e-mail MAILER-DAEMON was an user unknown message from an aol
subscriber.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Then either the person's account expired or AOL is messed up. You did
verify you typed the address correctly, no? If you think AOL is at fault,
complain to <A HREF="mailto:postmaster@aol.com"
>postmaster@aol.com</A>. (Ditto for any other site.) There's no
reason to write to MAILER-DAEMON, because there's nobody there to read it.
</BLOCKQUOTE>
<p><strong>
<img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Thank you for your prompt reply.
</strong></p>
<!-- end 18 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/20"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 20 -->
<H3 align="left"><img src="../gx/dennis/bbubble.gif"
height="50" width="60" alt="(!) " border="0"
>Loading SuSE Linux 6.4 via NFS</H3>
<p align="right"><strong>Answer By Chris Gianakopoulos
<br></strong></p>
<BLOCKQUOTE>
Hi all,
</BLOCKQUOTE>
<BLOCKQUOTE>
This weekend, I decided to load <A HREF="http://www.suse.com/">SuSE</A> Linux 6.4 onto my son's IBM
PS/ValuePoint computer.
</BLOCKQUOTE>
<BLOCKQUOTE>
The network configuration is illustrated below.
</BLOCKQUOTE>
<blockquote><pre> ----------------------- -------------------------
| | 10Base2 Ethernet | |
| IBM |----------------------| Linux Machine |
| PS/ValuePoint | | Host: stargate |
| Host: strikeforce | | with CDROM |
----------------------- -------------------------
Target machine for NFS server for
Linux install Linux install
</pre></blockquote>
<BLOCKQUOTE>
I have NFS running on my Linux machine, so I decided to install Linux
onto the IBM machine via NFS. I installed a minimal system so that I
could install user accounts in case problems occurred when I added more
packages to the system.
</BLOCKQUOTE>
<BLOCKQUOTE>
Once I had a minimal system up and running, I decided to use YAST (the
installation program) to added more packages into the system.
Everything worked fine until I was prompted to install CD2 of the
distribution. I was told that I was loading the wrong CD!
</BLOCKQUOTE>
<BLOCKQUOTE>
I investigated the problem by executing "tcpdump" on my Linux machine so
that I could observe traffic over the ethernet. To my surprise, I found
that the IBM machine was being denied access to CD2 (the second CD of
the SuSE distribution).
</BLOCKQUOTE>
<BLOCKQUOTE>
I then logged in as a user (not root) and then changed myself to root
with the 'su' command. This allowed me to mount remote filesystems
using NFS (for example:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQuote>
I decided to continue observing ethernet traffic while I manually (for
example: mount <TT>-t</TT> nfs stargate:/cdrom myMountDirectory, where
myMountDirectory is a local directory on host strikeforce). I now had a
controlled experiment, and I was able to determine that, out of the 6
CDs supplied with SuSE 6.4, CD number 2 could not be viewed, and this
was confirmed by the denied access packets observed via tcpdump on host
stargate.
</BLOCKQuote></BLOCKQUOTE>
<BLOCKQUOTE>
It turned out that, on CD number two the directory "." only had root
priviledges. On the other CDs, there existed read and execute
priviledge for group and world.
</BLOCKQUOTE>
<BLOCKQUOTE>
My solution was to copy the image of CD2 onto a top level directory of
my Linux machine (host stargate), make sure that group and world had
read and execute rights, and modify <TT>/etc/exports</TT> (the NFS export file
which allows other users to view your filesystem) to reference the
directory.
</BLOCKQUOTE>
<BLOCKQUOTE>
The lines in <TT>/etc/exports</TT> looks like this:
</BLOCKQUOTE>
<blockquote><pre>--------------------------------------- start of file ----------------
# used for all other CDs
/cdrom strikeforce(ro)
# used for CD number 2
/test/cdrom strikeforce(ro)
--------------------------------------- end of file ------------------
</pre></blockquote>
<BLOCKQUOTE>
I noticed one odd thing during this exercise (installing Linux via NFS).
</BLOCKQUOTE>
<BLOCKQUOTE>
Even though host strikeforce had unmounted the remote filesystem on
</BLOCKQUOTE>
<BLOCKQUOTE>
host stargate (I confirmed this via a telnet session onto host
strikeforce), I could not unmount my cdrom. In order to unmount the
cdrom, I had to comment out the line, in <TT>/etc/exports</TT>, which refers to
<TT>/cdrom</TT>, restart the NFS server by typing "nfsserver restart", and then
typing "unmount <TT>/dev/cdrom</TT>". I could then unmount the cdrom, change the
cdrom, mount the new cdrom, uncomment the abovementioned line in
<TT>/etc/exports</TT>, and restart the NFS server.
</BLOCKQUOTE>
<BLOCKQUOTE>
Perhaps, you do not have to unmount cdroms before changing them, but, I
would think that you would have to in order to maintain the proper
notion of the contents of the mounted cdrom.
</BLOCKQUOTE>
<BLOCKQUOTE>
The bottom line: My copy of SuSE Linux 6.4 does not have group and world
access rights to CD number 2, thus, you have to install from an image
copied onto the hard disk of the NFS server.
</BLOCKQUOTE>
<BLOCKQUOTE>
Perhaps this message is too long winded (I tend to ramble) for a 2 cent
tip. I'll let all of you decide if this message is worth posting. All
I know is that if I did not have strong networking and protocol
experience (my NFS knowledge is questionable), I wouldn't have known how
to use tcpdump, and I wouldn't have solved the problem in the speedy 5
hours that it took me.
</BLOCKQUOTE>
<BLOCKQUOTE>
Keep up the fantastic work, and thanks for all of your hard work for
this fine magazine!
</BLOCKQUOTE>
<BLOCKQUOTE>
Chris G.
</BLOCKQUOTE>
<!-- end 20 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/21"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 21 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>RE: classified disk</H3>
<p><strong>From Anonymous
</strong></p>
<p align="right"><strong>Answered By Ben Okopnik, Dan Wilder
<br></strong></p>
<P><STRONG>
Hey there gang! I was in the Air Force for almost 21 years and worked in
the intelligence career field. Depending on the level of classification the
overwrite method is not always allowable. Shane Welton needs to contact his
security manager for clarification. I took several computer security
courses taought by the NSA (yeah, I know the None Such Agency) and they
would not allow overwriting because they were able to recover all the data.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Heh. When I was in the Military Intelligence (yep, it's a non-sequitur
like "giant shrimp"), we dealt with NoneSuch; their "set in stone because
we say so" policies provoked a lot of comment among my fellow soldiers.
</BLOCKQUOTE>
<BLOCKQUOTE>
The ability to recover data through a simple format is the reason for the
7X overwrite method with random garbage. As long as 15 years ago, I
remember there being a guy in California who had a SQUID (Super-Conducting
Quantum Interference Detector) that could pull up a relatively high
percentage of data from a hard drive that had been through six low-level
formats (of course, he charged a few pennies for the privilege - $60k was
the figure I heard.) Those are typically just overwrites with all zeroes,
and he simply had to dig for a faint-but-present remainder of the original
ones and zeroes. He would try, but did not promise anything, with a
<EM>single</EM> data overwrite (I believe he was relying on the blank spots in the
current data.) After seven overwrites with random bits, there's <EM>nothing</EM>
of the original data left to be read - there's absolutely no way to
distinguish a '1' written seven overwrites ago from a '1' two overwrites
ago.
</BLOCKQUOTE>
<blockquote>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Dan]
If that's true, why not just overwrite seven times with all "0" or all
"1", on alternating passes? Or run "badblocks <TT>-w</TT>" which writes
all 0xaa, 0x55, 0xff, then 0x00, several times? Seems like it'd
be a lot faster than waiting for entropy on the <TT>/dev/*random.</TT> And,
it guarantees that every bit gets flipped multiple times.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
&lt;Shrug&gt; I always thought it would be sufficient, but the government spec
requires randomness. Given that "<TT>/dev/urandom</TT>" is non-blocking, I can't
see it as being much slower than any of the above, and I believe that a
pseudo-random source still qualifies - but given that my familiarity with
the pertinent regulations is from many years back, Your Mileage May Vary.
</BLOCKQUOTE>
</blockquote>
<BLOCKQUOTE>
If a company's the security policy disallows this kind of a solution, fine;
the technology is still a valid one.
</BLOCKQUOTE>
<p><em>... to which our spooky querent replies ...</em></p>
<p><strong>
<img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Yeah, I know what you mean. I dealt with SCI material, we couldn't even
think of declassifying anything. We finally got permission for me only
since in a prior life i was a machinist (my dad owned a machine shop) to be
able to take a hard drive apart, chuck up the drive platter and remove the
top .030 (thirty thousandths) on each side AND then we had to smash the
platter. The easiest thing was to just box up any drives and have the
courier take them up to Fort (Fumble) George G. Meade for them to destroy.
</strong></p>
<p><strong>
Hey, thanks for the trip down memory lane. Linux lives!!!
</strong></p>
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/22"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 22 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>multiple subnets, one DNS</H3>
<p><strong>From Damir Horvat
</strong></p>
<p align="right"><strong>Answered By Dan Wilder
<br></strong></p>
<P><STRONG>
Hello!
</STRONG></P>
<P><STRONG>
I have one linux server and 2 subnets on private network.
</STRONG></P>
<P><STRONG>
I would like to have this:
If the request (nslookup) come from subnet #1, DNS server would
show only the subnet #1 net table. And the other way around. The
two subnets should not "see" eachother.
</STRONG></P>
<P><STRONG>
any ideas?
</STRONG></P>
<P><STRONG>
kind regards,
<br>damir horvat
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Dan]
A so-called "split DNS" arrangement will do that.
</BLOCKQUOTE>
<BLOCKQUOTE>
Each subnet runs its own DNS server, which considers itself
authoritative for your domain. Each server forwards other
requests to one or more third servers, possibly those of your
ISP, which handle all other requests.
</BLOCKQUOTE>
<BLOCKQUOTE>
The server on subnet #1 has entries in its zone table
only for hosts on subnet #1, and for any outside
hosts belonging to your domain that need to be reachable
from subnet #1. Likewise, subnet #2.
</BLOCKQUOTE>
<BLOCKQUOTE>
Assuming your local subnets are 192.168.1.0 and .2.0
and that your ISPs nameservers are 10.0.0.1 and 10.0.0.2,
with BIND-8.2, your boot file (often <TT>/etc/named.conf</TT>),
has stanzas containing:
</BLOCKQUOTE>
<blockquote><pre>options {
directory "/var/named";
allow-query { 192.168.1.0/24; 127.0.0.1; };
notify no;
allow-transfer { none; };
datasize 20M;
forward only;
forwarders {
10.0.0.1;
10.0.0.2;
};
};
zone "your.domain." IN {
type master;
file "your.domain.zone";
};
</pre></blockquote>
<BLOCKQUOTE>
along with any other options and stanzas you need.
</BLOCKQUOTE>
<BLOCKQUOTE>
"<TT>/var/named/your.domain.zone</TT>" on each subnet lists <EM>all</EM> hosts
belonging to your domain that are visible from that subnet.
This includes any hosts off the subnet, as this setup will not
query the third-party DNS for hosts it doesn't know about in
your domain.
</BLOCKQUOTE>
<BLOCKQUOTE>
Substitute the proper IPs. Subnet #1 lists 192.168.1.0 network
in its allow-query field; subnet #2, 192.168.2.0. Hosts
on each subnet point to their own nameserver. If the subnet is
large enough to warrant the effort, set up two nameservers on each
subnet, the second a slave to or a mirror of the first, so the
subnet won't be left without name service if you have to take
the nameserver down.
</BLOCKQUOTE>
<BLOCKQUOTE>
If you have only one Linux server to implement this with,
run two copies of BIND, each listening only on the IP connected
to its respective subnet. Use the "listen-on" directive for that;
for more information, see "man named.conf.5".
</BLOCKQUOTE>
<p><em>... Damir replies ...</em></p>
<p><strong>
<img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Hello!
</strong></p>
<p><strong>
Thank you. Yesterday I've done some reading myself, and
successfuly setup one box with two NICs.
</strong></p>
<p><strong>
Kind Regards.
</strong></p>
<!-- end 22 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/23"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 23 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>responding to DESQview/386 Die Hards into the Next Millennia</H3>
<p><strong>From Jim Barnett
</strong></p>
<p align="right"><strong>Answered By Heather Stern
<br></strong></p>
<P><STRONG>
Jim,
</STRONG></P>
<P><STRONG>
I'm beginning the serious stage of a large AI project. For several reasons I (naturally) looked to Linux. However, what I really need is a robust but SIMPLE multitasking OS that will juggle my ANSI C code and stay out of the way. So far it looks like it may take the rest of my life to learn Linux, all the while I make no progress on my real project.
</STRONG></P>
<P><STRONG>
Then I remembered DESQview.
</STRONG></P>
<P><STRONG>
In a previous comment,
</STRONG></P>
<blockquote><font color="#00007f"><em>
<P><STRONG>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
I presume that Quarterdeck's aquisition by Symantec has spelled complete obscurity and orphanage to DV. They probably didn't even have the decency to release the sources to a "free world."
</STRONG></P>
<P><STRONG>
You might be far better off with a combination of Linux and its <A HREF="http://www.dosemu.org/">DOSEMU</A> or VMWare. It's a pity that you'd lose DESQview's UI (I'd really like to see a Linux console manager that would match the features and feel of the DESQview popup menu system --- but add configurability like DV/X). However you gain support for modern hardware (including CD's, CD-R, CD-RW, DVD and DVD-RAM) and procotols (running DV under a TCP/IP stack used to be like waltzing with a bear in a china shop!). You also lose all problems with memory management (forget about conventional vs. EMS and "largest program size").
</STRONG></P>
<P><STRONG>
All that and you get the sources, too. (A feature that would be even more exciting if I were a real programmer, and not just the occasional hack).
</STRONG></P>
</em></font></blockquote>
<p><strong>
you said it would probably not be possible to get Dv drivers for modern devices like CDROMs. Just doing some preliminary surfing today, it looks like you may be right. However, if I can find a copy of the actual program (there are tons of add-ons &amp; utilities online), I'd like to give DESKview a shot.
</STRONG></P>
<P><STRONG>
Assuming I stick with Linux, do you have any suggestions for shortening my learning curve? Is there a small, non-network, non-graphics release of Linux you would recommend?
</STRONG></P>
<P><STRONG>
Trying not to fall down the learning curve,
<br>Jim
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
Sorry to run a mite late, but you can easily consider Tom's Root Boot (it
runs off a floppy, needs no graphics whatsoever, and lives in RAMdisks) or
<A HREF="http://www.debian.org/">Debian</A> base (the install is a bit annoying, tho) - I think <A HREF="http://www.libranet.com/">LibraNet</A> can give
you a somewhat easier Debian setup without attempting to use graphics.
</BLOCKQUOTE>
<BLOCKQUOTE>
TomsRtbt is a libc5 based Linux system. Tom Oehser says he lives in it
day to day, and I assume he is able to use a compiler in it, since he creates
the code for new small utilities on his disk. It <em>does</em> have networking.
</BLOCKQUOTE>
<BLOCKQUOTE>
The advantage of Debian would be the ability to use their apt-get package
manager to fetch new applications or languages if you need them, eg. Lisp,
scheme, etc. The full-screen textmode utility 'console-apt' is also worth
the time to download, since you can use that to read descriptions of packages
that you're considering.
</BLOCKQUOTE>
<!-- end 23 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/24"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 24 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>DOS partition from Linux</H3>
<p><strong>From Rick Rodgers
</strong></p>
<p align="right"><strong>Answered By Mike Orr
<br></strong></p>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Does anyone know how to create a bootable DOS partition on a hardisk
using Linux? It seems that fdisk doesn't do it right and FreeDOS can
not boot.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
First, the DOS partition has to be a primary partition (one of the first four
partitions). Exactly one partition should be marked 'active' using fdisk.
This is the partition that will boot. If the DOS partition is active, you
will boot only into DOS. If your Linux partition is active AND you set up
LILO, or if you set up LILO on the master boot record, you can choose Linux
or DOS from the LILO menu. See the LILO documentation in <TT>/usr/doc/lilo/</TT> or
thereabouts, and the LILO HOWTO and the other HOWTOs at
<a href="http://www.linuxdoc.org/">www.linuxdoc.org</a>.
</BLOCKQUOTE>
<BLOCKQUOTE>
Actually, there is a DOS program called loadlin that will allow you to first
boot DOS, then go into Linux, but usually people use LILO instead.
</BLOCKQUOTE>
<BLOCKQUOTE>
I don't know about FreeDOS, but in MS-DOS or you have to copy the system files
in order to make a bootable disk. You can do that when you format the disk
by using the <TT>/s</TT> option to the DOS FORMAT command, or by using the DOS SYS
command to copy the system files from a disk that already has then (e.g., a
bootable floppy: &quot;<tt>SYS A: C:</tt>&quot
<IMG SRC="../gx/dennis/smily.gif" ALT=";)"
height="24" width="20" align="middle">. The required files are <tt>IO.SYS</tt>, <tt>MSDOS.SYS</tt> and
<TT>COMMAND.COM</TT>. IO.SYS and MSDOS.SYS are hidden files in the root of your C:directory (or A:\ on bootable floppies). COMMAND.COM is the DOS shell that
gives you the C:\&gt; prompt. Without these three files, the DOS partition is
not bootable.
</BLOCKQUOTE>
<BLOCKQUOTE>
In Windows95, these same three files and commands are used, and bring up Win95
in MS-DOS mode (without the GUI). For the GUI, you'll have to install Windows.
If you have the Windows installation files on a CD, you can copy them to the
DOS partition from Linux, boot DOS somehow, and then run the Windows SETUP.EXE
program. You probably won't be able to use the CD-ROM from DOS without
Windows; that's why you'd need to copy the setup files to the hard drive first.
</BLOCKQUOTE>
<BLOCKQUOTE>
All bets are off with Windows 2000.
</BLOCKQUOTE>
<BLOCKQUOTE>
If this doesn't answer your question, tell us more specifically what the
problem is (what error messages you're getting, what partitions you have),
and that may help us give a better answer.
</BLOCKQUOTE>
<!-- end 24 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/25"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 25 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>e-mails not getting through</H3>
<p><strong>From DJ Bellerose
</strong></p>
<p align="right"><strong>Answered By Mike Orr
<br></strong></p>
<p><strong>
Dear James,
</strong></p>
<p><strong>
Could you please give me some info as to why my e-mails are not being
recieved by the intended recipient. After sending them I do not get them
back in my own mail saying that they were undeliverable. I have on
occasion gotten some back but the ones I am sending to my boyfriend are
not getting to him although it says they are being sent. I have sent a
few and then have gone to his place so we could see what was happening
but nothing shows in his mailbox. All my other e-mails do make it to
whomever I send them to. Also the e-mails I have sent to my boyfriend
before have made it but for some reason in the past week and a half none
of them were sent to his mailbox. I know I have the right addy as he has
been here with me when we sent some. I hope you can help with this. If
you need his addy or mine I will send them to you upon request. When
they do come back to me it is from Mailer Daemon.
</strong></p>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
This is the biggest clue right here. It should be an error message
saying (perhaps cryptically) why the mail is being returned. Also look
at the headers of the original message (which the error message will
hopefully include). Every mail system the message passes through will
add a Received: line before the other Received: lines. Did the message
go all the way to his ISP? Can you write to his ISP's tech support
address or to <A HREF="mailto:postmaster@his-isp.com"
>postmaster@his-isp.com</A>? You need to determine whether it's
only his address that's failing or all addresses at his ISP.
</BLOCKQUOTE>
<BLOCKQUOTE>
If you are on a Linux system (which you are, right, since you wrote to
<en>Linux Gazette</em>?), look in your mail log (in <TT>/var/log/mail</TT> or
<TT>/var/log/exim</TT>, etc) to verify the message was successfully sent off
your computer and where it was sent to.
</BLOCKQUOTE>
<!-- end 25 -->
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<A NAME="tag/26"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 26 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Exiting X and Rebooting with One Keystroke</H3>
<p><strong>From stefan
</strong></p>
<p align="right"><strong>Answered By Ben Okopnik, Jim Dennis
<br></strong></p>
<!-- ::
Exiting X and Rebooting with One Keystroke
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
:: -->
<P><STRONG>
i've following problem:
i've set up a couple linux-pc's with X, but w/o a windowmanager, on which i
run an icaclient (citrix, u know!).
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
I'm not familiar with Citrix/ICA client, but a quick look at their website
tells me that the solution that I had in mind would work, as long as you
can create either desktop or toolbar icons.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
now for shutting down the computer the user first has to exit
X (by ctrl+alt+backspace) an can then press ctrl+alt+del.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Try creating an icon that runs "super halt". A number of people out there
don't like "super", but as far as I know, its security problems
(particularly the "buffer overflow" bug) have been fixed, and it is very
handy for something like this. "super" allows a user to run a specific
command as if they were root, which "halt" requires. When I did this
myself, initially, I was concerned about some possibility of creating a
problem by not exiting X directly, but then realized that it was simply an
old MS-Windows mental block: after all, "Ctrl-Alt-BkSp" kills X; what can
shutting down do that's any worse?
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
If you always want to reboot after exiting X then just start X
with a script like:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQUOTE><CODE>
#!/bin/sh
<BR>startx
<BR>exec /sbin/shutdown -r now
</CODE></BLOCKQUOTE></BLOCKQUOTE>
<BLOCKQUOTE>
... so any exit from X will then execute the next line of your shell
script. I'm sure there are more elegant ways. You might even want
to patch the X sources to use [Ctrl]+[Alt]+[Del] as the "Zap"
key instead of [Ctrl]+[Alt]+[Backspace]. I don't know of an option
to configure that. However, I haven't even looked at XFree86 version
4.x yet!
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
but this is a little to complicated (very dumb users
<IMG SRC="../gx/dennis/smily.gif" ALT="; )"
height="24" width="20" align="middle">).
i'm looking for a possibility to assign a key-combination
(eg. ctrl+alt+f12) for shutting down X and the pc in one step.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
I don't know how this would be any different from simply hitting
"Ctrl-Alt-Del", unless "ica-client" intercepts that. If it doesn't, simply
make sure that your "<TT>/etc/inittab</TT>" contains lines that look like this:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQUOTE><CODE>
# What to do when CTRL-ALT-DEL is pressed.
<BR>ca:12345:ctrlaltdel:/usr/bin/super /sbin/halt
</CODE></BLOCKQUOTE></BLOCKQUOTE>
<BLOCKQUOTE>
Hint: if you make "halt" an alias for "super halt", everyone who is
authorized via "<TT>/etc/super.tab</TT>" will be able to shut down the machine
simply by typing "halt" in an xterm.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
thanks,
stefan
</STRONG></P>
<P><STRONG>
ps: sorry for my bad english.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
I find that most folks who apologize for their English - and yours is fine,
by the way - tend to be far more understandable (since they make an effort
to be understood) than native english speakers who write in with things
like "dOOdz U got 2 hepl mE My proBlM nVIDIa caRD WhaT I dO noW?????????"
It's not even the kOOl or 3l33t slang, but simply the fact that they don't
take the trouble to relay any useful information... oops, one of my
favorite rants. I'll stop now.
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</BLOCKQUOTE>
<!-- end 26 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/27"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 27 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Multiplexing ppp connections</H3>
<p><strong>From David Hunt
</strong></p>
<p align="right"><strong>Answered By Ben Okopnik
<br></strong></p>
<P><STRONG>
Dear Answer Gang
</STRONG></P>
<P><STRONG>
I have a RedHat 6.1 box that we use for dial out internet
access using ppp at 19200 baud. We would like to increase
our bandwidth, but according to our ISP the only way we can
do this, due to their system, is to have two dial out
connections and multiplex them together or have one for
outgoing and the other for incoming.
</STRONG></P>
<P><STRONG>
Is this possible to do in linux?
</STRONG></P>
<P><STRONG>
Where can I find documentation about how to do this?
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Oh-oh. Time for me to put on The Curmudgeon Hat. The "baud vs. bps"
confusion is one of my Rant Topics (don't worry; it's a general rather
than a directed rant.)
</BLOCKQUOTE>
<BLOCKQUOTE>
If you are indeed connecting at 19200 baud (and that is far from certain),
it means absolutely nothing - unless you're doing something like packet
radio stuff, in which case you'd be dealing with the raw numbers. "baud"
refers to the actual switching frequency of the modem, which, given the
communication protocols in use today, bears less and less relation to the
bps (bytes per second) transmitted or received - the only thing that we
really care about, as it is the "real" data transfer rate (barring some
esoteric considerations.)
</BLOCKQUOTE>
<BLOCKQUOTE>
(By the way, doing a search for "bps baud confused" on Google produces
over 7,000 hits. Don't feel like you're alone.
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</BLOCKQUOTE>
<BLOCKQUOTE>
Let's see... by using Deep Magic, I can see that you're coming out of (or
at least e-mailing from) the Great State of Texas. Chances are pretty high
that the average ISP down thataway will let you connect at speeds up to
56k (nominally, that is; 53k is the actual upper limit due to phone system
voltage restrictions, unless they've changed it and forgot to notify me
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
If your ISP is restricting you to something below that, changing your ISP
is probably the best bet.
</BLOCKQUOTE>
<BLOCKQUOTE>
Now, all that out of the way - if you actually do want to multiplex two
modems, and your ISP supports the scheme - and according to what you've
written, they do, then, yes, Linux does indeed support modem multiplexing.
Take a look at the "eql" package in the distribution, as well as
</BLOCKQUOTE>
<BLOCKQUOTE>
"<TT>/usr/src/kernel-source-&lt;version&gt;/Documentation/networking/eql.txt</TT>"
</BLOCKQUOTE>
<BLOCKQUOTE>
in the source tree. (This assumes that you have the kernel source
installed.) Note that modem multiplexing of this sort does not decrease
your latency, which is an entirely different issue and has quite a lot to
do with perceived "speed" of communications.
</BLOCKQUOTE>
<BLOCKQUOTE><dl><dt>
Also, check out Robert Novak's "EQL HOWTO" -
<dd><A HREF="http://home.indyramp.com/masq/eql/eql.html"
>http://home.indyramp.com/masq/eql/eql.html</A>
</dl></BLOCKQUOTE>
<BLOCKQUOTE>
Pretty good stuff for load balancing info, which sounds like what you're
trying to do - unless switching ISPs is a better answer.
</BLOCKQUOTE>
<p><em>... David responds ...</em></p>
<P><STRONG>
<img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Thanks very much for your quick reply. This was exactly what I
was after. After hearing about EQL from you I have since found a
lot of info about it.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
You are certainly welcome; I'm very glad that the information was of use
to you.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Just to let you know why I'm after multiplexing 2 19200bps lines.
Firstly we are not in the States but in the middle of Asia.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Ah. 'sil.org' is in Texas, and I gather you're posting via their web/mail
interface. If your ISP is AsiaOnLine.net, you have my profound sympathy; I
have several acquaintances who are vehement about calling it AphasiaOnLine
(it "forgets" a high percentage of their mail) and are unanimous in cursing
it to high heaven.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Also
there is only one ISP in our area and for some reason or another
they say the max connection speed is 19200bps. One last
complication is we don't have a land line but only a microwave
connection to the nearest town.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Well - sounds like load-balancing experimentation is not a hobby for you
but more of a necessity. I must say that I find it interesting that your
ISP supports EQL; I assume you realize that it has to be supported at both
ends. Since they are the ones who suggested it, they most likely do. I wish
you the best of luck.
</BLOCKQUOTE>
<!-- end 27 -->
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<A NAME="tag/28"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 28 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>[Tony@thermo-king.com: new to Linux]</H3>
<p><strong>From Tony Ormsby
</strong></p>
<p align="right"><strong>Answered By Heather Stern
<br></strong></p>
<P><STRONG>
Hi;
</STRONG></P>
<P><STRONG>
I am currently a Windows 98ME user. I have recently started studying Linux
OS at Tech.
I am looking at installing Linux onto an old PC at home to start with before
looking at possibly
replacing my current OS later on down the track.
My old PC is a i386 with 8Mb of RAM and about 250Mb of HDD space.
I am about to ask some silly questions which I hope you may be able to help
me with.
</STRONG></P>
<P><STRONG>
Firstly, for such an old system, is there a Linux OS available for it? (with
or without a GUI)
Secondly, I have an old Linux OS (similar to the old MS-DOS 3.3 OS) which I
am playing with
and am looking at writing a script which will help me to do the following:
</STRONG></P>
<strong><ul>
<li> advise user of terminal
<li> advise user of others logged on
<li> make an ext2 file system on a floppy
<li> mount a floppy at a location /mnt/floppy
<li> unmount the floppy from /mnt/floppy
<li> display date
<li> create back up of users home directory to floppy
<li> display current directory
<li> exit menu script.
</ul></strong>
<P><STRONG>
Actually, I'm also going through some old books but they don't five examples
of how these scripts
should be approached. I'm hoping that if I can get an example, it will give
me more of an idea on how
Linux directory system operates.
It does appears that the floppy drive once mounted becomes part of the root
directory rather than remain
a seperate drive as in MS OS .
</STRONG></P>
<P><STRONG>
I would like to know more about Linux. I believe that in the next few years,
it will grow more competitive
and become a real alternative to Windows.
I also have a copy of <A HREF="http://www.redhat.com/">Red Hat</A> 6.2 which I am looking at putting onto a spare
i486 with 16MB RAM
which I have in pieces.
I have been told however, that Mandrake 7.0 is a much easier alternative
when starting out in Linux.
I guess I'm looking for some help in determining which direction I'm going.
</STRONG></P>
<P><STRONG>
kind regards;
Tony Ormsby
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
<A HREF="http://www.debian.org/">Debian</A> can run easily in the limitation you described - its "base" only
uses about 60 Mb or so. (might be less, I haven't really counted it).
Graphical setups cost a lot more space - you should avoid using weighty
applications like Emacs, the big environments like Gnome, K or the Office
Suites, because they will be very slow for you, if you even get them to fit.
</BLOCKQUOTE>
<BLOCKQUOTE>
You probably want to investigate some of the specialty distributions listed
at Linux Weekly News (<a href="http://www.lwn.net/">www.lwn.net</a>).
</BLOCKQUOTE>
<BLOCKQUOTE>
Whichever distro you use for the 386, make sure that you are fairly minimal
about what you allow it to install. You might even consider calling the
staff for the companies (in the case of corporate distributions like <A HREF="http://linux.corel.com/">Corel</A>
or Redhat) and asking them what is the minimum space they can be installed
in, and the minimum RAM that configuration will run with.
</BLOCKQUOTE>
<BLOCKQUOTE>
The 486 you describe has a better chance of using something fairly ordinary,
though you'll probably still want to be picky about how to use your disk
space. Again, 16 Mb is okay but a bit low, so the weightier apps won't be
all that happy in it.
</BLOCKQUOTE>
<BLOCKQUOTE>
Mandrake is a nice distro (when it works at all in your system) but since
it is optimized for 586 or higher-powered processors only, it won't work on
either of the two systems you mentioned. Sorry.
</BLOCKQUOTE>
<BLOCKQUOTE>
If you have to, you can always use a much earlier distribution (though it
will have the security bugs that plagued those releases) or you can use a
"mini" distribution - usually optimized for running from floppies, but many
of them can be carefully set up to run from hard disks as well.
</BLOCKQUOTE>
<BLOCKQUOTE>
Tom's root boot is a nice tiny distro (floppy based) to use to learn more
about things under Linux without getting too complex. It runs from RAM so
you don't have to ruin any harddisks until you decide what you want to do.
Of course, its documentation is very minimal, because too much wouldn't fit
on a floppy. You can find his work at <A HREF="http://www.toms.net/rb"
>http://www.toms.net/rb</A>
</BLOCKQUOTE>
<BLOCKQUOTE>
Best of Luck
</BLOCKQUOTE>
<!-- end 28 -->
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<A NAME="tag/29"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 29 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Trident Providia 9685</H3>
<p><strong>From J C White
</strong></p>
<p align="right"><strong>Answered By Heather Stern
<br></strong></p>
<P><STRONG>
Hi There,
</STRONG></P>
<P><STRONG>
I was told you might be able to direct me to where I can
find the drivers (Win98SE) for the Trident PV 9685...I have
this PCI vid
card with no drivers...I also have the AGP version...again
no drivers
</STRONG></P>
<P><STRONG>
any assistance will be greatly appreciated
</STRONG></P>
<P><STRONG>
J C White
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
The card that you have has actually come up before in The Answer Guy column,
in issue 31. (<A HREF="../issue31/tag_trident.html">www.linuxgazette.com/issue31/tag_trident.html</A>) It's been
supported in <A HREF="http://www.redhat.com/">Red Hat</A> (at least on a hardware list) since at least version
4.2. So, the card's been around awhile, and we can at least assure you that
it works for Linux...
</BLOCKQUOTE>
<BLOCKQUOTE>
Unfortunately that's not what you've asked. Sadly, we have no particularly
great idea where to find just about anything specific for Windows (any
revision)... that's not the OS we write about.
</BLOCKQUOTE>
<BLOCKQUOTE>
However, I do find an occasional gem for Windows (when I have to go looking)
at either winfiles.com, or TUCOWS. That's short for: The Ultimate Collection
Of Windows Software. They've of course spread out into more OS flavors and
hardware such as Palm pilots andd our fave, Linux.
</BLOCKQUOTE>
<BLOCKQUOTE>
Under Linux, the card you mention works under Xfree86 version 3.3.6 as well
as the new, restructured to be nice and fast, 4.0. I even saw a mention of
a 64-bit version of it being okay (AGP wasm't mentioned over in the list at
www.xfree86.org, but I'm guessing that's what you really have). Metro-X has
a commercial server for it too.
</BLOCKQUOTE>
<BLOCKQUOTE>
Though it's mentioned in scattered references as "unsupported" I have to add
that in Linux terms, that means Trident has been worthless in helping us use
their stuff, so it doesn't mean exactly that it doesn't work, it means that
we probably are not making the card behave at its very best. We might be -
we might even do a better job than your missing Windows drivers - but we
really can't tell. Not a lot of developers will throw extra money at more
pieces of unusable hardware if they should fry one while trying to code things
to make it work.
</BLOCKQUOTE>
<BLOCKQUOTE>
To be utterly fair to Trident, there aren't that many companies that are
"supported" in the sense of really giving us data that we can use for coding
up new X server support. It's kind of strange that vendors won't help, even
with some raw information about expected input and output signals, since they
claim they want to sell hardware. Even if it would somehow reveal some great
secret about their hardware (I find this difficult to believe), you don't see
very many companies helping us out even with their <EM>older</EM> cards, saving juicy
protectionism for the Hottest New Toy. There are a few... <A HREF="http://www.suse.com/">SuSE</A> and Precision
Insight have given a lot of extra help to the X Free86 project by helping
convince and aid vendors in going our route... as for the others, too bad for
them. We tend to buy what we can use, and we're really good at friendly word
of mouth for helpful vendors. So if things don't work out for you (though I
hope they do), allow me to recommend 3D Labs, ATI (we handle so many ATI cards
I stopped counting them. Get a Rage 128 and save yourself from wondering
which server entry to pick), Matrox (Milleniums are excellent), 3Dfx, or any
of the other vendors who've done XFCom servers. They can use the
encouragement
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</BLOCKQUOTE>
<BLOCKQUOTE>
[Note]
3dfx appears to be effectively out of business since Nvidia bought them,
which might not matter to you, but it seemed wise to mention, as you might
not want to buy cards that have been orphaned that way.
</BLOCKQUOTE>
<p><em>... John went on to find the REAL answer he needed ...</em></p>
<P><STRONG><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
found ALL drivers and will forward to list...even found
jumper settings to use as SVGA, S-Vid, or NtSC output in
Win95 or 95; again , will send....gimme addy where to upload
these gems to as well as a Trident total support page with
drivers for everything they ma(de)ke!!
</STRONG></P>
<P><STRONG>
Thanks Again
</STRONG></P>
<P><STRONG>
John
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
You can reply to <A HREF="mailto:linux-questions-only@ssc.com"
>linux-questions-only@ssc.com</A> and I'll publish ... mainly because the
jumper details might be useful to Linux'ers too. If you create
your own web page where you're keeping track of these, you can tell
us the link. And, that'd make it pretty easy for you to submit the
tip to Windows related sites, as well.
</BLOCKQUOTE>
<BLOCKQUOTE>
I don't know if Trident maintains such a "total support page" - do
they? But as time marches on, lots of companies stop maintaining
details for older cards.
</BLOCKQUOTE>
<BLOCKQUOTE>
[Note] John didn't forward the drivers, but if anybody needs to get ahold of
him for these, send a note to The Answer Gang (<A HREF="mailto:linux-questions-only@ssc.com"
>linux-questions-only@ssc.com</A>) and I'll
forward it along to him.
</BLOCKQUOTE>
<!-- end 29 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/30"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 30 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>The New network On The BLock</H3>
<p><strong>From Robert Smith
</strong></p>
<p align="right"><strong>Answered By Dan Wilder
<br></strong></p>
<P><STRONG>
Next year i'm hoping to set up a home network that will have internet connection through a firwall, then a DSL connection. With such a set up, is there any need to set up DNS services if we are to have a static IP address, or can we use the ISP's?
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Dan]
You can use the ISP's DNS services. Put internal hostnames in
the <TT>/etc/hosts</TT> files, or equivalent for other OSs, and point
all hosts to the ISPs nameservers for resolution of external
hosts. On Linux, <TT>/etc/host.conf</TT> should read
</BLOCKQUOTE>
<blockquote><pre>order hosts,bind
multi on
</pre></blockquote>
<BLOCKQUOTE>
and <TT>/etc/resolv.conf</TT> should have:
</BLOCKQUOTE>
<blockquote><pre>search your.internal.domain
nameserver IP.for.your.ISPs.nameserver
nameserver IP.for.another.of.your.ISPs.nameserver
</pre></blockquote>
<BLOCKQUOTE>
"your.internal.domain" is whatever you call your network. No need
for it to be a registered domain. "IP.for.your.ISPs.nameserver"
is the IP number for your ISP's nameserver.
</BLOCKQUOTE>
<BLOCKQUOTE>
It becomes worthwhile to set up an internal nameserver when
the internal network grows large enough to make propogating
the <TT>/etc/hosts</TT> files (and equivalent) a nuisance. There are
a couple of other reasons to set up internal nameservers ...
consigning external banner ad servers to oblivion, for example ...
but AFAIK, these are all amenities you can easily live without.
</BLOCKQUOTE>
<!-- end 30 -->
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<A NAME="tag/31"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 31 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Mail Daily sylog message to remote e-mail</H3>
<p><strong>From Ling Ling
</strong></p>
<p align="right"><strong>Answered By Ben Okopnik
<br></strong></p>
<P><STRONG>
Hi,
</STRONG></P>
<P><STRONG>
I am sorry about the interruption. But I have no way to find a help except
to try my luck everywhere I can (at least that's what I perceived). I have a
RH 6.2 server running as FTP server. Upon customer response, I will have to
send certain syslog message to their LAN account, like say <em>admin@system.com</em>.
I have read all the manual and even posted up a question on the linux
mailing list, but I have still no receiving the answer I want ... I now how
to redirect to a file or a local user, but this users is not a local system
users (but stay in the same domain), do you mind to guide me on this ??
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
I'm not exactly sure of what you're asking, but here is my best guess:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQuote>
1) You have a user connecting via FTP.
2) On a response (What kind of response? What kind is <EM>possible</EM> via
FTP?), you want to send e-mail to that user.
</BLOCKQuote></BLOCKQUOTE>
<BLOCKQUOTE>
Assuming that the response - however it's done - contains the user's name
and host, the answer is an easy one:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQUOTE><CODE>
tail /var/log/messages | mail -s "Your syslog info" <A HREF="mailto:Username@Host"
>Username@Host</A>
</CODE></BLOCKQUOTE></BLOCKQUOTE>
<BLOCKQUOTE>
The above, for example, would send the last 10 lines of
"<TT>/var/log/messages</TT>" to the specified user. You can, of course, specify
whatever information you want to send, and use whatever subject you want
(the '<TT>-s</TT>' switch on the above command line) - this is purely an example,
since you didn't say what it is that you wanted from the syslog. Note that
you may have a decision to make with regard to file permissions, as most
log files are only readable by 'root'.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Thank you very much.
</STRONG></P>
<P><STRONG>
Regards,
Ling Ling
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
You're welcome. If I'm off in my understanding of what you're trying to
do, please feel free to write back.
</BLOCKQUOTE>
<!-- end 31 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/33"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 33 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Scripted Serial Sessions</H3>
<p><strong>From nir
</strong></p>
<p align="right"><strong>Answered By Jim Dennis
<br></strong></p>
<!-- ::
Scripted Serial Sessions
~~~~~~~~~~~~~~~~~~~~~~~~
:: -->
<P><STRONG>
Hellow
</STRONG></P>
<P><STRONG>
I am qa engineer
</STRONG></P>
<P><STRONG>
I want to write send and recieve file script for minicom, so i will
be able to check a lot off AT commands. do you know about any tools
that could help me, or examples for those scripts.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
Read the man pages:
</BLOCKQUOTE>
<blockquote><pre>RUNSCRIPT(1) RUNSCRIPT(1)
NAME
runscript - script interpreter for minicom
SYNOPSIS
runscript scriptname [homedir]
DESCRIPTION
runscript is a simple script interpreter that can be
called from within the minicom communications program to
automate tasks like logging in to a unix system or your
favorite bbs.
</pre></blockquote>
<BLOCKQUOTE>
runscript is a utility that comes with minicom.
</BLOCKQUOTE>
<BLOCKQUOTE>
Of course, I can't just leave it at that. That would be far
too simple an answer. I really have to put in a plug for
Kermit if you're going to be doing any serious communications
scripting. Kermit is a rich programming/scripting language for
automating serial and network communications. I really suggest
that you try it instead of minicom's runscript.
</BLOCKQUOTE>
<BLOCKQUOTE>
I must admit that I usually use minicom for most of my simple
interactive serial terminal needs. However that's purely born of
laziness. Minicom is included with most LInux distributions while I'd
have to fetch kermit and build it from sources. If it was
"apt-get'able" from the <A HREF="http://www.debian.org/">Debian</A> archive system; I'd go back in a
heartbeat.
</BLOCKQUOTE>
<BLOCKQUOTE>
All of that aside, runscript can probably do what you need,
and if that doesn't give you enough power to do the job then
look at the 'expect' programming language from Don Libes. That
can automate any terminal/curses appllication under Linux/UNIX
and it supports the full TCL programming language. There is also
an "expect.pm" module for PERL if you prefer its syntax and features.
</BLOCKQUOTE>
<p><strong>
<img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Thank you.
</strong></p>
<p><strong>
Kermit is very good but their is one problem, i cant put AT commands in my
script.
i have the same problem in minicom (it dowsnt recognize AT commands)
i try even to combine the both (minicom and kermit).
i think kermit is powerful and thanks to you i learn it.
</strong></p>
<p><strong>
thanks again!!!
<br>Nir
</strong></p>
<!-- end 33 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/34"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 34 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Setting up print filters.</H3>
<p><strong>From Neo
</strong></p>
<p align="right"><strong>Answered By Ben Okopnik
<br></strong></p>
<P><STRONG>
Hi,
</STRONG></P>
<P><STRONG>
I'm a totally newbie about Linux, but I found it a real great OS (I
normally used Win98 !!!), but I have a small problem. I have just changed
my printer, a brand new Epson Stilus Color 670, but my Linux box won't use it
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
The main reason, Neo, is - of course - that the Matrix has you.
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</BLOCKQUOTE>
<BLOCKQUOTE>
Generally, I would not respond - few people would - to a request for help
that gives so little useful information. The reason that I'm answering this
question at all is because printing setups can be troublesome, and what I
want to do here is write a sort of a mini-troubleshooting guide. "My Linux
box won't use it" is rather useless; what does that mean? Are you
physically unable to connect the printer to the box? Does it not fit on the
same desk as the computer? Does it print perfectly except for skipping
every other comma? There is no way to tell, and most of us aren't into
guessing. Please try to make yourself clearer when asking for help; there's
no such thing as "too much information" when doing so.
</BLOCKQUOTE>
<BLOCKQUOTE>
If there's one bit of advice that I'd want to emphasize to the newcomers
in the Linux community, this would be it - make yourself as clear as
possible when asking for help, and include as much information as you
think necessary... and then add some more.
</BLOCKQUOTE>
<!-- ::
Check the hardware for compatibility.
~~~
:: -->
<BLOCKQUOTE>
A quick check of Epson's website didn't give me any specs on this printer,
just advertising crud. I suspect, though, that it is not a WinPrinter -
that's what I wanted to check up on. If it was, you'd have a bit of trouble
(software is available, but it's problematic.) In any case, WinPrinters
are beyond the scope of what I want to cover. We'll assume that you have a
real, honest-to-goodness printer with its own brain, and go from there.
</BLOCKQUOTE>
<!-- ::
Test the hardware at the lowest level of complexity.
~~~
:: -->
<BLOCKQUOTE>
Once you have connected the parallel cable (once again, USB printers are
outside the scope - look up the USB-HOWTO on the Web), powered up the
machine and the printer (DO NOT connect or disconnect parallel peripherals
under power: you stand a high chance of frying the peripheral and the
machine), and made sure that the printer's power light is on, it's time
for the basic test. Pick a text file that is about 1k in size - the
default "<TT>/etc/inittab</TT>" is a pretty fair example - and shove it straight out
through the parallel port:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQUOTE><CODE>
cat /etc/inittab &gt; /dev/lp0
</CODE></BLOCKQUOTE></BLOCKQUOTE>
<BLOCKQUOTE>
This assumes two things: 1) that you are logged in as root, and 2) that
the first parallel port, "lp0" (known as "LPT1:" under DOS/Windows) is
where your printer is connected.
</BLOCKQUOTE>
<BLOCKQUOTE>
If this doesn't work, look at any error messages that may be generated:
"Permission denied" probably means that you *didn't* log in as root.
"Device not configured" would mean that you either don't have the "lp"
module loaded (check by typing "lsmod") or do not have the kernel
parallel-port driver enabled, which would be a strange thing to do (but
I've seen it happen.)
</BLOCKQUOTE>
<BLOCKQUOTE>
If no error messages are generated and there's still no output, try
assuming that it's the other parallel port - there are rarely more than
two on machines today; for that matter, more than one is becoming rare.
Anyway, try
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQUOTE><CODE>
cat /etc/inittab &gt; /dev/lp1
</CODE></BLOCKQUOTE></BLOCKQUOTE>
<BLOCKQUOTE>
- it can't hurt.
</BLOCKQUOTE>
<BLOCKQUOTE>
One rare, odd thing that can make this test fail - check the parallel port
settings in your BIOS. I've seen an "ECP/EPP" setting disable a Brother
printer under both Linux and Windows; all other settings allowed it to
work. Yes, Brother printers are weird - but this was about as strange as
snake suspenders...
</BLOCKQUOTE>
<BLOCKQUOTE>
If none of the above works, check the hardware by booting into DOS or
Windows and printing from there. If you still can't get it to print,
there's a problem with your hardware - port, cable, or printer. Curse life,
weep loudly, and replace whatever is necessary.
</BLOCKQUOTE>
<!-- ::
Setting up the printer spooler.
~~~
:: -->
<BLOCKQUOTE>
Install "lpr" or "lprng". For a home user, it makes no difference which
one you choose. Either one handles the tricky bit with the permissions -
you don't have to be root to print anymore. "cupsys", available with the
new version of <A HREF="http://www.debian.org/">Debian</A> (and probably other distros) takes care of this and
the next (filtering) stage. Make sure your "<TT>/etc/printcap</TT>" is correct (see
"man printcap") and test the system by typing
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQUOTE><CODE>
lpr /etc/inittab
</CODE></BLOCKQUOTE></BLOCKQUOTE>
<!-- ::
Setting up print filters.
~~~
:: -->
<BLOCKQUOTE>
If all you were going to do is print text, you'd be done at this point.
However, most folks like their graphics and want to pretty-print stuff
like Web pages, etc. For this, you need a series of "translators" that
accept an arbitrary file type and turn it into language that is
appropriate for your printer. "magicfilter" and "apsfilter", in my
experience, can both be rather fussy about installation - I've had
problems with both. Test the system by printing a <EM>small</EM> graphics file,
preferably something like a black 4x4 pixel GIF or JPG - if you only get a
dot (the correct output), try a larger image; if the filters are messed
up, you won't get more than a page of random garbage.
</BLOCKQUOTE>
<BLOCKQUOTE>
At this point, you're done. The next move, as the original Neo said, is up
to you.
</BLOCKQUOTE>
<!-- end 34 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/35"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 35 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Xwindows</H3>
<p><strong>From Wes Ragle
</strong></p>
<p align="right"><strong>Answered By Mike Orr, Heather Stern
<br></strong></p>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Is Xwindows a generic
part of Linux? All I ever see while researching the question is xfree86?
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
"Linux" refers only to the kernel. All Linux software comes from third
parties, including stuff that's necessary to boot and produce a shell
prompt. X-windows is just a protocol; Xfree86 is a concrete
implementation of that protocol.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
Actually strictly speaking, X is the protocol, windows are what it is about
painting, and people rarely see them apart unless they are programming an
X based application. Especially if they're programming a window manager;
window managers (whose names often end in wm: fvwm, qvwm, twm, flwm, icewm;
but not necessarily: blackbox, enlightenment, sawfish) are responsible for
listening to X protocol messages like "you got clicked" or "keystroke M" or
"please repaint coordinates so-and-so" and telling the right applications
what to do. It's the window manager that owns the scrollbars, the title
bar, and the background.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
XFree86 describes itself as "a non-profit organisation which produces
XFree86, a freely redistributable open-source implementation of the X
Window System that runs on UNIX(R) and UNIX-like (like Linux, the BSDs,
Mac OS X (aka Darwin) and Solaris x86 series) operating systems and
OS/2." (<A HREF="http://www.xfree86.org"
>http://www.xfree86.org</A>)
</BLOCKQUOTE>
<BLOCKQUOTE>
Linuxers adopted Xfree86 over other versions of X-windows because (1) it
runs on the x86 CPUs (a sine que non), (2) it's affordable (back when X
was unusable under Linux I almost bought BSDi [another UNIX-like OS]
instead, but didn't because of its price tag), and (3) meets our
standards for open source (not counting a few minor squabbles along the
way).
</BLOCKQUOTE>
<BLOCKQUOTE>
Linuxers chose X-windows over other graphical systems (e.g., MGR)
because almost all the graphical applications available for UNIX are
designed for X.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
There are other implementations of X, also... tinyX is one. You can read
far more than any of us can say here by following some of the links at
Kenton Lee's site:
<A HREF="http://www.rahul.net/kenton/xsites.html"
>http://www.rahul.net/kenton/xsites.html</A>
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Four other graphical "systems" to look at are the framebuffer, SVGAlib,
Berlin and GGI.
</BLOCKQUOTE>
<BLOCKQUOTE>
The framebuffer is an optional part of the Linux kernel
that runs the video card in graphics mode. This is required for
non-Intel systems (which don't have a text mode, so it must be
emulated). It's also useful on Intel because X-windows normally takes
control of the video card itself, and because X is such a huge beast,
buggy X programs and drivers can crash the X server, freezing the
screen+keyboard+mouse and necessitating a reboot. But with the
framebuffer, the kernel retains control of the video card and can tell
the X server where to go.
</BLOCKQUOTE>
<BLOCKQUOTE>
SVGAlib is a library that allows non-X programs to use graphics mode.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
However, there's only one fellow in charge of it and video cards keep moving
onward. Last I saw, he's not adding support for new cards - although many
with VESA 2.0 compatability will work.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Berlin is/was a project to make a windowing system better than X. I
can't find a URL for it, so I'm not sure if it still exists. (I thought
it was www.berlin.org, but that goes to www.berlin.de, which contains
tourist information about the city. Google and MetaCrawler don't seem
to have any links to it.)
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
Funny, I went to Google, typed in the keywords "berlin" and "gui" and it
popped right up:
<A HREF="http://www.berlin-consortium.org"
>http://www.berlin-consortium.org</A>
</BLOCKQUOTE>
<BLOCKQUOTE>
The trick is to make sure you don't get references to the city, by putting
in a more limiting keyword to go with it
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle"> They have news as of late
November, so I guess the project is still alive.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
GGI ("General Graphics Interface",
<A HREF="http://www.ggi-project.org"
>http://www.ggi-project.org</A>) is a portable graphics interface
of the "write once, run anywhere" variety. It can run with X and/or the
framebuffer and in other combinations.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Would you please straighten me out as to
exactly what is involved in generating nice graphics in Linux? Does Mesa
only work with drivers for a select few video chips?
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
I'll let others answer these since I don't know.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
I don't think that is the case... although certain video chips may get a
significant boost from having OpenGL support directly, Mesa is software that
allows non-supporting cards to display applications designed around OpenGL.
Mostly. The author is very careful to state that it is not a licensed SGI
implementation of OpenGL so if something isn't a perfect match, sorry. You
can read all about that at the Mesa project homesite, again not quite obvious:
<A HREF="http://www.mesa3d.org"
>http://www.mesa3d.org</A>
</BLOCKQUOTE>
<BLOCKQUOTE>
Anyways I hope that helps a bit. Since I don't know what kind of nice graphics
you're trying to do, I don't know if any of the APIs optimized for helping
gamers might help you out too. But this should be a good start.
</BLOCKQUOTE>
<!-- . . . . . . . . . . . . . . . . . . . -->
<HR WIDTH="40%" ALIGN="center">
<!-- begin 35 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Xfree 4.0.2</H3>
<BLOCKQUOTE><dL>
<dt>Definitely worth mentioning --
Xfree86 4.0.2 just came out. Release notes:
<dd><A HREF="http://www.xfree.org/4.0.2/RELNOTES.html"
>http://www.xfree.org/4.0.2/RELNOTES.html</A>
</ul></BLOCKQUOTE>
<!-- end 35 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/36"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 36 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>diald on a smoothwall box</H3>
<p><strong>From jim watkins
</strong></p>
<p align="right"><strong>Answered By Mike Orr
<br></strong></p>
<P><STRONG>
This may be the wrong place to ask a question! in which case please take no
notice.However if not......
</STRONG></P>
<P><STRONG>
I just made a box running smoothwall, a sucess until....I realized it
did not dial on demand...then I found diald ....to me this looks like
it should achieve what I want...
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
<br>1) What are you trying to do?
</BLOCKQUOTE>
<BLOCKQUOTE>
2) What's smoothwall?
</BLOCKQUOTE>
<BLOCKQUOTE>
Diald's main use is to automatically initiate a ppp connection when
there's outgoing traffic at your site but the link is down, and then
to tell ppp to hang up when the outgoing traffic has been idle for a
certain period of time.
</BLOCKQUOTE>
<BLOCKQUOTE>
For an ordinary firewall situation with ppp and an analog modem, where
you want the connection to go up and down automatically as needed, yes,
you would use diald.
</BLOCKQUOTE>
<BLOCKQUOTE>
Note that diald cannot measure <EM>incoming</EM> traffic when the link is
down. This would require something like diald at the ISP's end.
</BLOCKQUOTE>
<!-- end 36 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/37"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 37 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>...a bulk friendly ISP?</H3>
<p><strong>From needbulkisp
</strong></p>
<p align="right"><strong>Answered By Jim Dennis
<br></strong></p>
<!-- ::
...a bulk friendly ISP?
~~~~~~~~~~~~~~~~~~~~~~~
:: -->
<BLOCKQUOTE>
[the editor notes that the querent sent his mail as all HTML. Yuck.]
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Hello!
</STRONG></P>
<P><STRONG>
I'm trying to find a bulk friendly ISP, to host a very small website.
Can you help?
</STRONG></P>
<P><STRONG>
OR
</STRONG></P>
<P><STRONG>
Can you refer me to anyone?
</STRONG></P>
<P><STRONG>
Thanks very much,
</STRONG></P>
<P><STRONG>
HAPPY NEW YEAR!
</STRONG></P>
<P><STRONG>
From: <A HREF="mailto:needbulkisp@yahoo.com"
>needbulkisp@yahoo.com</A>
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Jim]
I don't know what you mean by "bulk friendly." However, you should
be aware that the phrase carries very negative connotations to
experience internet professionals.
</BLOCKQUOTE>
<BLOCKQUOTE>
To must of us that suggests that you are planning to spam (e-mail)
people and you want to hook up with an ISP that will tolerate your
abuse of the Internet and shield you from the wrath of the people
that you offend.
</BLOCKQUOTE>
<BLOCKQUOTE>
Since you say it's a "very small website" I presume that you don't
mean that you have a "bulk" of content that you wish to make
available. Perhaps you mean that you have a small volume of content
that you believe will get an immense amount of traffic. Obviously
there are lots of ISP and co-location facilities out there. For
commercial traffic they are <EM>very</EM> "bulk friendly" (since they
charge for all the traffic --- the more traffic you generate, the
more money they charge and the friendlier they get).
</BLOCKQUOTE>
<BLOCKQUOTE>
Anyway, I'll refrain from suggested actual companies here. Among
other things I don't know enough about your needs and resources
(money) to make any reasonable suggestions, and I'm not in the
business of shopping for ISPs (bulk-friendly or otherwise).
</BLOCKQUOTE>
<BLOCKQUOTE>
However, I've left your name in this message since your
e-mail address is clearly and solicitation for relevant advertising.
I'm sure that "bulk friendly" ISPs will just be banging down your
inbox within a few days. (Normally we filter e-mail addresses
out of LG Answer Gang articles to protect or correspondents from
spammers; however this appears to be a "trowaway" e-mail account
which will be abandonned as soon as you've made your selection
--- so I'll suggest to my editors that we make an exception in your
case).
</BLOCKQUOTE>
<!-- end 37 -->
<center>
<H1><A NAME="tips"><IMG ALIGN=MIDDLE ALT="" SRC="../gx/twocent.jpg">
More 2&cent; Tips!</A></H1> <BR>
Send Linux Tips and Tricks to <A HREF="mailto:gazette@ssc.com">gazette@ssc.com</A></center>
<!-- BEGIN tips -->
<UL>
<!-- index_text begins -->
<li><A HREF="#2c/1"
><strong>Let cron put backup files into your Gnome trashcan</strong></a>
<li><A HREF="#2c/2"
></a>Baffled --or--
<br><A HREF="#2c/2"
><strong>Seeing what's changed since your tar backup</strong></a>
<li><A HREF="#2c/3"
><strong>2cent tip: lynx mpg123 and mp3.com</strong></a>
<li><A HREF="#2c/4"
></a>Dohhh! Check if your screen is really locked --or--
<br><A HREF="#2c/4"
><strong>The Unattended Risk</strong></a> Lock your system!
<li><A HREF="#2c/7"
><strong>Modem Question - Easy One</strong></a>
<li><A HREF="#2c/9"
><strong>Monitor goes blank in X</strong></a>
<li><A HREF="#2c/12"
><strong>Tips: sendmail offline</strong></a>
<li><A HREF="#2c/13"
><strong>Measure your modem connection - Bogospeed</strong></a>
<li><A HREF="#2c/14"
><strong>2-cent tip - module resource detection</strong></a>
<li><A HREF="#2c/15"
><strong>Backup via shell script</strong></a>
<li><A HREF="#2c/17"
><strong>devices list</strong></a>
<li><A HREF="#2c/19"
><strong>Linux core files</strong></a>
<li><A HREF="#2c/21"
><strong>linux login problem</strong></a>
<li><A HREF="#2c/23"
><strong>networked machine goes to sleep?</strong></a>
<li><A HREF="#2c/24"
><strong>NT Log on a Linux Box</strong></a>
<li><A HREF="#2c/25"
><strong>Graphics Programming for Printing / Faxing (Issue 60)</strong></a>
<li><A HREF="#2c/26"
><strong>About RS422</strong></a>
<li><A HREF="#2c/27"
><strong>x-base languages for Linux</strong></a>
<li><A HREF="#2c/28"
><strong>NT Event Reporting in Unix/Linux</strong></a>
<li><A HREF="#2c/29"
><strong>Need Outlook to speak to Linux</strong></a>
<li><A HREF="#2c/31"
><strong>Fat 32 Linux instillation</strong></a>
<li><A HREF="#2c/32"
><strong>Available spcae avail on Hd!</strong></a>
<!-- index_text ends -->
</UL>
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="2c/1"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Let cron put backup files into your Gnome trashcan</FONT></H3>
Sat, 30 Dec 2000 01:02:24 -0500
<BR>From: Allan Peda (<a href="mailto:linux-questions-only@ssc.com?cc:tl082@yahoo.com">tl082@yahoo.com</a>)
<BLOCKQUOTE>
Cron to put bacup files in trash (if you have a gnome desktop):
</BLOCKQUOTE>
<BLOCKQUOTE>
I typed this up to keep my home dir clean, it assumes backup files over
1 day old should
be moved to the trashcan. I run it every 5 minutes under cron
</BLOCKQUOTE>
<BLOCKQUOTE><pre>
#!/bin/sh
# script to move trash files to trash can
# use cron to run this every 5 minutes
if [ x"$HOME" = x ]; then
echo "\$HOME not defined"
exit 1
fi
TRASHCAN=${HOME}'/.gnome-desktop/Trash/'
if [ ! -d $TRASHCAN ]; then
echo "Need a trash can to work"
exit 1
fi
FARGS=' -maxdepth 1 -type f -mtime +1 '
find ~ $FARGS -name '.saves-*' -exec mv {} $TRASHCAN \;
find ~ $FARGS -name '\#*\#' -exec mv {} $TRASHCAN \;
</pre></BLOCKQUOTE>
<!-- sig -->
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<P> <A NAME="2c/2"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Seeing what's changed since your tar backup</FONT></H3>
Fri, 29 Dec 2000 09:35:11 -0800
<BR>Jim Dennis (<a href="mailto:linux-questions-only@ssc.com">The Answer Guy</a>)
<BLOCKQuote>
(If you have a full tar backup of your root and <TT>/usr</TT> filesystems
you can use the '<tt>tar df</tt>' or '<tt>tar dzf</tt>' directives to report on
differences between your current files and those in your backup.
</BLOCKQuote>
<!-- sig -->
<!-- end 2 -->
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<P> <A NAME="2c/3"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">2cent tip: lynx mpg123 and mp3.com</FONT></H3>
Mon, 11 Dec 2000 19:58:01 -0800
<BR>From: collver@softhome.net(<a href="mailto:linux-questions-only@ssc.com?cc:collver@softhome.net">collver@softome.net</a>)
<BLOCKQUOTE>
mp3.com uses MIME to describe audio content to web browsers.
A year or two ago, mp3.com had instructions to set up audio/mpeg and
audio/mpegurl in Netscape. These MIME types no longer work because
mp3.com now uses audio/x-mpeg and audio/x-mpegurl instead.
</BLOCKQUOTE>
<BLOCKQUOTE>
Two places to configure viewers for MIME types:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQuote>
/etc/mailcap
$HOME/.mailcap
</BLOCKQuote></BLOCKQUOTE>
<BLOCKQUOTE>
I suggest editting $HOME<tt>/.mailcap</tt> as it overrides <TT>/etc/mailcap</TT>.
</BLOCKQUOTE>
<BLOCKQUOTE>
You might already have entries placed by Netscape. If so, they assume you
only use X and they look like:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQUOTE><CODE>
#mailcap entry added by Netscape Helper
<BR>audio/x-scpls;xmms %s
<BR>#mailcap entry added by Netscape Helper
<BR>audio/x-mpegurl;xmms %s
<BR>#mailcap entry added by Netscape Helper
<BR>audio/x-mpeg;xmms %s
</CODE></BLOCKQUOTE></BLOCKQUOTE>
<BLOCKQUOTE>
If you don't want to use xmms, delete these lines.
If you want to use xmms when in X, replace '<TT>xmms %s</TT>'
with '<TT>xmms %s; test=test -n "$DISPLAY"</TT>'
</BLOCKQUOTE>
<BLOCKQUOTE>
Then add:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQuote><code>
audio/x-scpls; mpg123 -@ %s
<br>audio/x-mpegurl; mpg123 -@ %s
<br>audio/x-mpeg; mpg123 $s
</code></BLOCKQuote></BLOCKQUOTE>
<!-- sig -->
<!-- end 3 -->
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<P> <A NAME="2c/4"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">The Unattended Risk</FONT></H3>
Thu, 28 Dec 2000 18:57:54 -0800
<BR>allan
<P><STRONG>
I realized the other day that locking your screen is next to useless if
you start your linux box in text mode, performing a "startx &amp;" to begin
an X session, <em>unless</em> you Ctrl-Alt-F1 to your text virtual console
and Ctrl-D logout, then you can Ctrl-Alt-F7 back to the X console, and
lock the screen. Otherwise all a passerby need do is switch virtual
terminals and use you account.
</STRONG></P>
<P><STRONG>
It's sorta obvious when you think about it. Of course an unattended
Linux machine is not really secure, but still, just switching virtual
consoles is a little <em>too</em> easy.
</STRONG></P>
<P><STRONG>
Allan
</STRONG></P>
<BLOCKQUOTE>
I've been doing "<tt>exec startx</tt>" from non-xdm machines to save myself
having to log out when I quit my X session. I think it would help with
this situation too. -- Don Marti
</BLOCKQUOTE>
<BLOCKQUOTE>
... or
<br><code>startx &amp; vlock</code>
<br>... to ensure that your login session will not be
inadvertantly be left unlocked and unattended.
</BLOCKQUOTE>
<BLOCKQUOTE>
Naturally you'll also want to look at xautolock --- adding
it to your .Xclients, .xsession or other
windowing system start-up/configuration files as necessary.
<br> -- Jim Dennis
</BLOCKQUOTE>
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<P> <A NAME="2c/7"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Modem Question - Easy One</FONT></H3>
Sun, 17 Dec 2000 19:59:45 EST
<BR>From: Franklyn
(<a href="mailto:linux-questions-only@ssc.com?cc:I3utane@aol.com">I3utane@aol.com</a>)
<p><strong>
Answer Guy,
</strong></p>
<p><strong>
I've read an response that you posted about a win modem running in linux, it
wont'. But I it was posted on Feb 22, 1999. So I was hoping that came out
and gave us the source and stuff. I have a US Robotics 56k Voice Win. If
they haven't, i'm out to comp usa to buy a external 3 comm (or is a internal
ok?).
</strong></p>
<p><strong>
Be good man - thanx in advance.
</strong></p>
<p><strong>
Franklyn
</strong></p>
<BLOCKQUOTE>
See if <A HREF="http://linmodems.org"
>http://linmodems.org</A> or the Linmodem Mini HOWTO
www.linuxdoc.org/HOWTO/Linmodem-HOWTO.html+linmodem&amp;hl=en
help.
</BLOCKQUOTE>
<BLOCKQUOTE>
An external modem is usually better anyway because modems generate
a lot of heat, plus external modems don't have any OS-specific
idiosynchracies.
</BLOCKQUOTE>
<BLOCKQUOTE>
--
Mike Orr
</BLOCKQUOTE>
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<P> <A NAME="2c/9"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Monitor goes blank</FONT></H3>
Sun, 24 Dec 2000 15:29:28 +0200
<BR>From: Marius Andreiana
<P><STRONG>
I'd like to turn off blanking of the monitor in X. After 10 min or so
it goes blank, so I have to move the mouse from time to time when
watching movies
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</STRONG></P>
<P><STRONG>
I've tried setterm <TT>-blank</TT> 0 before starting the movie (put that in
rc.local too)
but no effect. setterm <TT>-blank</TT> 60 won't work either.
</STRONG></P>
<BLOCKQUOTE>
setterm affects only the console. My ~/.xsession has the following
command:
</BLOCKQUOTE>
<BLOCKQUOTE>
&quot;`
xset dpms 1800 2400 3600
&quot;'
</BLOCKQUOTE>
<BLOCKQUOTE>
which blanks the screen at 30 minutes, goes into power-save mode at 40
minutes, and "off" at 60 minutes. I use such a long time so it doesn't
blank out when I'm moving back and forth between the computer and the
kitchen.
</BLOCKQUOTE>
<BLOCKQUOTE>
There are also some options in XF86Config you can try. See
"man 5 XF86Config-v3" or "man 5 XF86Config". You have to put in a
"power_saver" option; then set the BlankTime, StandbyTime, SuspendTime,
and OffTime in the Screen section. These are overridden by xset.
</BLOCKQUOTE>
<BLOCKQUOTE>
--
Mike Orr
</BLOCKQUOTE>
<BLOCKQUOTE>
You're on the right track but in the wrong lane. The setterm
command only affects the (virtual) <EM>terminal</EM> settings. You
want the xset command.
</BLOCKQUOTE>
<BLOCKQUOTE>
Try the command:
</BLOCKQUOTE>
<blockquote><pre> xset s off
</pre></blockquote>
<BLOCKQUOTE>
... from any xterm. Then start your moving, kick back, and
watch the show.
<br>-- Jim Dennis
</BLOCKQUOTE>
<!-- end 11 -->
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<P> <A NAME="2c/12"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Tips: sendmail offline</FONT></H3>
Tue, 26 Dec 2000 23:35:19 +0100 (MET)
<BR>From: Karl-Heinz Herrmann
(<A HREF="mailto:k.-h.herrmann@fz-juelich.de"
>k.-h.herrmann@fz-juelich.de</A>)
<BLOCKQUOTE>
Hi,
</BLOCKQUOTE>
<BLOCKQUOTE>
since I just solved a little nuisance with the newer Sendmail 8.9.3 on my system I
thought it could help somebody else.
</BLOCKQUOTE>
<BLOCKQUOTE>
My setup: dialup connection, local sendmail is handling all outgoing e-mail and is
</BLOCKQUOTE>
<BLOCKQUOTE>
queuing them until online. In my ppp-start scripts sendmail will then be
triggered by '<TT>sendmail -q</TT>' to run the queue.
</BLOCKQUOTE>
<BLOCKQUOTE>
Now since the last upgrade this didn't always work for mails sent offline but would
work for mails sent while I was online. I now found out that sendmail is keeping a
persistent host status directory.
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQUOTE><CODE>
sendmail.cf says:
<BR>-------
<BR># persistent host status directory
<BR>O HostStatusDirectory=.hoststat
</CODE></BLOCKQUOTE></BLOCKQUOTE>
<BLOCKQUOTE>
[...]
</BLOCKQUOTE>
<BLOCKQUOTE>
O Timeout.hoststatus=60m
---------
</BLOCKQUOTE>
<BLOCKQUOTE>
So if a mail was undeliverable (offline) sendmail would remember that for 60m. Only
then it would ever try it again even if online and '<TT>sendmail -q</TT>' is run.
This status seems to be associated with each mail, so new ones go out, old ones
stay.
</BLOCKQUOTE>
<BLOCKQUOTE>
Possible solutions:
</BLOCKQUOTE>
<BLOCKQUOTE><ol>
<li> reduce the timeout to 1m or similar.
<br>or
<li> run '<tt>sendmail -bH</TT>' as well in the ppp-start script. This will purge the
host status cache.
</ol></BLOCKQUOTE>
<BLOCKQUOTE>
I Hope this helps others to get a similar setup working faster then me
<IMG SRC="../gx/dennis/smily.gif" ALT=";-)"
height="24" width="20" align="middle">
</BLOCKQUOTE>
<BLOCKQUOTE>
-- Karl-Heinz Herrmann
</BLOCKQUOTE>
<!-- end 12 -->
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<P> <A NAME="2c/13"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Measure your modem connection - Bogospeed</FONT></H3>
Sat, 16 Dec 2000 11:44:11 -0500
<BR>From: Ben Okopnik (<a href="mailto:linux-questions-only@ssc.com">of The Answer Gang</a>)
<BLOCKQUOTE>
This one does a 'bogo-measurement' of the modem connection speed. Given
that I'm in the process of playing with a rather shitful internal modem
(bleagh!), it comes in very handy.
</BLOCKQUOTE>
<BLOCKQUOTE>
Several times, I've seen people write in to LG and ask "How can I tell how
fast my modem connection is?" This little script will... well, it'll do
_something_ that will at least give you an idea.
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</BLOCKQUOTE>
<BLOCKQUOTE>
In the tradition of "BogoMIPS", "bogospeed" gives you a <EM>relative</EM> value
of your connection speed. This means that the numbers you see do not
represent the actual speed of your connection <TT>-</TT> in my experience, they are
about 25% high <TT>-</TT> but give you a general idea of what you should expect.
If, for example, you normally see "55000 bps" as your 'bogospeed', and you
see "33000 bps" on a given connection, you'll know that the connection
you've just made is about 40% slower than usual (and that you should
probably try reconnecting.)
</BLOCKQUOTE>
<BLOCKQUOTE>
"bogospeed" normally takes about 10-15 seconds to do its stuff on a decent
connection with a 56k modem, and MUCH longer on a very slow connection. To
stop you from wasting your time, it prints the time that is required for
the first 'ping' to reach your ISP, as well as the time that it takes to
execute that ping. In my experience, if that execution time is much longer
than 3 seconds, you've got a poor connection and should try redialing.
</BLOCKQUOTE>
<BLOCKQUOTE>
Ben Okopnik
</BLOCKQUOTE>
<BLOCKQUOTE><pre>
#! /bin/bash
# Estimates connection speed to your ISP
# Be nice to MindSpring; put in your own ISP's name here
ISP="www.mindspring.com"
# Check if 'traceroute' is installed on the system
[ -z `which traceroute` ] &amp;&amp; {
echo "\"${0:2}\" requires 'traceroute' to be installed."
exit
}
# Check if 'bing' is installed on the system
[ -z `which bing` ] &amp;&amp; {
echo "\"${0:2}\" requires 'bing' to be installed"
exit
}
remote=`time traceroute -m 1 $ISP 2&gt;/dev/null|awk '{gsub("\(|\)","");print $3 " " $4}'`
echo
echo -e "Ping time to ISP:" ${remote:15} "ms\nMeasuring speed...\n"
bing -c 1 -e 20 -S 1024 localhost ${remote:0:14} 2&gt;&amp;1|grep throughput
</pre></BLOCKQUOTE>
<!-- end 13 -->
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<P> <A NAME="2c/14"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">2-cent tip - module resource detection</FONT></H3>
Sat, 16 Dec 2000 11:19:44 -0500
<BR>From: Ben Okopnik (<a href="mailto:linux-questions-only@ssc.com">of The Answer Gang</a>)
<BLOCKQUOTE>
Here's a rather nifty script I've crufted. Given the number of times I've
seen people have problems with loading modules, I think it would be pretty
useful.
</BLOCKQUOTE>
<BLOCKQUOTE>
Actually, this two-cent tip is more like a dime (hey, I worked hard on this thing!
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle"> Recently,
I installed <A HREF="http://www.debian.org/">Debian</A> 2.2 (potato). For various reasons <TT>-</TT> namely, the fact
that I've got a weird soundcard <em>and</em> decided to play around with an
internal (yechhh) PnP modem <TT>-</TT> I needed to load several modules that
required various combinations of IRQs, DMAs, and I/O addresses. Having
suffered with this in the past, I decided, once and for all, to resolve
the mess.
</BLOCKQUOTE>
<BLOCKQUOTE>
If you are trying to load a module, and failing with a "Device or resource
busy" error, then 'shotgun' is just what you need. It will try to load your
module with permutations of the three supplied lists for the above values.
It's smart enough to figure out which modules don't require any parameters,
as well as warning you about modules that require other things. It will, as
a last resort, try to load the module with "auto" values, and will give you
good advice on what to do if everything else fails. All in all, it's a very
useful tool if you're going to load modules for strange hardware. It will
also let you know what the correct values are when it <em>does</em> succeed; this
allows you to write them into "<TT>/etc/modules</TT>" and forget them: they'll be
auto-loaded the next time you boot.
</BLOCKQUOTE>
<BLOCKQUOTE>
Happy resource hunting to all!
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</BLOCKQUOTE>
<BLOCKQUOTE>
Ben Okopnik
</BLOCKQUOTE>
<BLOCKQUOTE><pre>
#!/bin/bash
#
# Requires bash, basename, cat, find, grep, insmod/lsmod, strings
[ -z "$1" ] &amp;&amp; {
cat &lt;&lt; @END@
* 'shotgun' - a parameter guessing routine for module loading *
*** Copyright Ben Okopnik 2000 - released under the GNU GPL ***
Syntax: `basename $0` module_name
@END@
exit
}
# Parameter value lists - make sure the 'iolist' makes sense for your
# hardware!
#
# Note that '0' is not an actual value - it tells the module to try
# a default value. This usually works, but is not the best thing.
irqlist="3 4 5 6 7 8 9 10 11 12 13 14 15 0"
dmalist="1 2 3 4 5 6 7 0"
iolist="200 210 220 230 240 250 260 270 280 290 2a0 2b0 2c0 2d0 2e0 2f0 300 310 320 330 340 350 360 370 380 390 3a0 3b0 3c0 3d0 3e0 3f0"
# Clipping the ".o" for uniform syntax
module=${1#\.o}
fname=$(find /lib/modules -name ${module}.o)
[ -z "$fname" ] &amp;&amp; {
echo "No module called \"$module\" exists under /lib/modules."
exit
}
clear
warn
parms="$(strings -a $fname|grep ^parm)"
for p in $parms
do
par=${p#parm_}
echo ${par%=*}
done
[ -z $par ] &amp;&amp; {
echo "This module does not require any parameters. Loading..."
insmod $module &amp;&amp; echo -e "\n$module loaded.\n"
exit 1
} || {
echo -e "\nPress a key to start the test process or 'Ctrl-C' to quit."
}
read
echo -e "This might take a while...\n"
echo -n "Running"
for irq in $irqlist
do
for dma in $dmalist
do
for io in $iolist
do
echo -n "."
result="$(insmod $module irq=$irq dma=$dma io=0x$io 2&gt;/dev/null)"
invalid=$(echo "$result"|grep -c invalid)
unresolved=$(echo "$result"|grep -c unresolved)
if [ $(($invalid+$unresolved)) -eq 0 ]
then
out=$(lsmod|grep ^$module)
echo
echo
if [ -z "$out" ]
then
badnews
else
echo "If the module loaded successfully, you should see"
echo "its name on the following line:"
echo ${out% *}
echo
echo "The parameter values were: irq=$irq dma=$dma io=0x$io"
echo
exit
fi
fi
done
done
done
function badnews()
{
clear
cat &lt;&lt; @END@
Oops. It didn't load. OK, try typing "insmod $module" and see what it
says - if you get a whole bunch of 'unresolved symbol' messages, that
means there's another module that needs to be loaded before this one;
take a look in "/lib/modules/&lt;version&gt;/modules.dep" to find out what
that might be. Other than that, here are a few things to try:
1) Modify the values in the parameter lists at the beginning of this
script: the IRQ and the DMA ranges are probably OK, but the IOs can vary
widely - make sure they make some kind of sense for your module. This
might mean looking at the paperwork that came with your hardware or
starting up Windows to see what I/O address it's been assigned there.
2) Load the values manually. The module you're trying to load may
require more than just IRQ, DMA, and IO - the parameter list at the
start of this program will show you all the possibilities.
3) Do some more research on what the appropriate value ranges for your
module might be. Search the Web for your hardware name plus "linux" - I've
usually had good success with Google and AltaVista's "advanced" search.
4) Often, reading the appropriate part of the kernel source - even if
you are not a programmer - can be very helpful. As a good example,
reading the source for the SoundBlaster/ESS module - 'sb_ess.c' in the
'/usr/src/kernel-source-&lt;version&gt;/drivers/sound/' directory - enabled me
to get my WAV files to play at normal speed, by using the "esstype=1688"
parameter; it was explained in the comments near the top of the file.
The source files tend to be about half code and half comments: the good
folks that write them *want* you to understand.
Good luck!
@END@
exit
}
function warn()
{
cat &lt;&lt; @END@
NOTE: The following is a list of parameters your module can accept; usually,
most of these are not required. Most often, 'irq', 'io', and 'dma' are all
that are necessary; this script will try to load your module with various
values of those parameters.
If after pressing a key you do not see all three of these - 'irq', 'dma',
_and_ 'io' - on the list, you should probably quit the script by pressing
'Control-C', as the module will almost certainly fail to load despite the
lack of error messages. If the module takes <EM>no</EM> parameters, the script
will notify you of that and load it properly.
* Press 'Enter' to see the parameter list *
@END@
read
}
</pre></BLOCKQUOTE>
<!-- end 14 -->
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<P> <A NAME="2c/15"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Backup via shell script</FONT></H3>
Thu, 14 Dec 2000 11:27:58 -0600
<BR>From: Michael Williams (not from the answer gang)
<P><STRONG>
How do you back up your home file system to a remote system using shell
script
</STRONG></P>
<BLOCKQUOTE>
If the computers are connected via TCP/IP and you have rsync and ssh
installed on both machines, do:
</BLOCKQUOTE>
<BLOCKQUOTE><pre>
#!/bin/sh
# backup.sh
rsync -av --delete -e ssh /local/dir/ user@remote_computer:/remote/dir
</pre></BLOCKQUOTE>
<BLOCKQUOTE>
Put a slash at the end of the first argument but not on the second
argument. Try it first running rsync on the command line with option
<TT>-n</TT> added, to see what it would do. Otherwise you may discover you're
specifying the wrong directory and deleting stuff you don't want to delete.
</BLOCKQUOTE>
<BLOCKQUOTE>
You will have to configure ssh to let your script login without a
password. If you don't have an ssh public key yet, run "ssh-keygen".
Then copy your local ~/.ssh/identity.pub to the remote
~/.ssh/authorized_keys . (Or append to authorized_keys if you already
have some entries in it).
</BLOCKQUOTE>
--
Mike Orr
</BLOCKQUOTE>
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<P> <A NAME="2c/17"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">devices list</FONT></H3>
Thu, 14 Dec 2000 12:15:11 +0100
<BR>From: Monserrat Seisdedos Nu<4E>ez
<P><STRONG>
Hello those in the gazette:
</STRONG></P>
<P><STRONG>
My question is :
</STRONG></P>
<P><STRONG>
there is any <TT>/dev/devices</TT> list where it is pointed out which device
belongs to???
that is
<br>hdx--&gt; hard disks
<br>fdx--&gt; floppy disks
<br>etc...
</STRONG></P>
<BLOCKQUOTE>
Download the kernel source (any version) and look at
Documentation/devices.txt .
</BLOCKQUOTE>
<BLOCKQUOTE>
--
Mike Orr
</BLOCKQUOTE>
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<P> <A NAME="2c/19"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Linux core files</FONT></H3>
Wed, 13 Dec 2000 15:10:02 -0500
<BR>From: ken ramseyer
<P><STRONG>
I read your article in
<A HREF="../issue41/tag/4.html"
>http://www.ibiblio.org/mdw/LDP/LG/issue41/tag/4.html</A> which talks about
Linux core files.
</STRONG></P>
<P><STRONG>
Do you know of any reasons why a core file would go to a directory other
than the current working directory (cwd)?
</STRONG></P>
<BLOCKQUOTE>
I thought core files always went to the current directory. Meaning,
the current directory <EM>of the process that was killed</EM>.
</BLOCKQUOTE>
<P><STRONG>
Do you know if there is a way to tell the Linux kernel where to put core
files?
</STRONG></P>
<BLOCKQUOTE>
Not that I know of.
</BLOCKQUOTE>
<BLOCKQUOTE>
I have "ulimit <TT>-c</TT> 0" in my .zshrc to prevent core files from being written
at all. That affects the shell process and all its descendants. Since
I'm not (much of) a C programmer, core files are useless to me.
</BLOCKQUOTE>
<BLOCKQUOTE>
Initscript(5) says that if you have a shell script called
<TT>/etc/initscript</TT>, init will use it for every process it spawns.
"This script can be used to set things like ulimit and umask default
values for every process." Since init is the anscestor of everything,
this would be a way to stamp out all core files at once.
</BLOCKQUOTE>
<BLOCKQUOTE>
--
Mike Orr
</BLOCKQUOTE>
<!-- sig -->
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<P> <A NAME="2c/21"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">linux login problem</FONT></H3>
Wed, 27 Dec 2000 15:57:40 -0800
<BR>From: Joseph Cheek to Howard Hsu...
<P><STRONG>
I have found posts of yours which seem to relate to a
problem I am currently having. Any help which you
might provide would be greatly appreciated.
</STRONG></P>
<P><STRONG>
We are having trouble logging into our linux server
via the console or telnet, but are able to login using
the same l/p for ftp.
</STRONG></P>
<BLOCKQUOTE>
what are the permissions on <TT>/etc/securetty?</TT>
</BLOCKQUOTE>
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<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">networked machine goes to sleep?</FONT></H3>
Sun, 03 Dec 2000 18:41:56 -0500
<BR>From: Christopher Curtis
<BLOCKQUOTE>
This problem exists, or used to exist, for several people, including
myself. The concensus is that the problem has to do with a cisco
router: The router expects chatty windows machines that crash <TT>-</TT> if your
Linux box just sits around not saying anything, cisco assumes it's dead
and stops routing traffic towards it. There's a config option in the
router that can turn this 'feature' off, but, as for myself, I cron a
ping since I can't access the router.
</BLOCKQUOTE>
<BLOCKQUOTE>
Christopher
</BLOCKQUOTE>
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<P> <A NAME="2c/24"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">NT Log on a Linux Box</FONT></H3>
Wed, 13 Dec 2000 11:15:27 -0600
<BR>From: Jonathan Hutchins
<BLOCKQUOTE>
Boy, talk about "think outside the box...". [Cesar] complained that he
couldn't cron the dumpel.com program to dump the NT Event Log to a flat file
for viewing on Linux. While it isn't called cron, NT does have a scheduler.
The command line interface is "at", and a GUI interface comes with the
Resource Kit. Yes, he needs admin privileges on NT to schedule it, but he'd
need root if he were trying the same thing on a Linux box.
</BLOCKQUOTE>
<BLOCKQUOTE>
There are also various programs to give you a remote virtual console from an
NT box. We use PCAnywhere within Windows environments, but the VNC project
might be very useful... <A HREF="http://www.uk.research.att.com/vnc"
>http://www.uk.research.att.com/vnc</A>
</BLOCKQUOTE>
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<P> <A NAME="2c/25"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Graphics Programming for Printing / Faxing (Issue 60)</FONT></H3>
Tue, 5 Dec 2000 01:50:32 -0500 (EST)
<BR>From: Anthony E. Greene
&lt;<A HREF="mailto:linux-questions-only@ssc.com?cc:agreene@pobox.com"
>agreene@pobox.com</A>&gt;
<BLOCKQUOTE>
The quick and easy way for a Perl programmer to do convert data to faxable
invoices/reports is to output the data as HTML, convert it to Postscript
using html2ps &lt;<A HREF="http://www.tdb.uu.se/~jan/html2ps.html&gt"
>http://www.tdb.uu.se/~jan/html2ps.html&gt</A>;, then fax the
result using efax or mgetty+sendfax.
</BLOCKQUOTE>
<BLOCKQUOTE>
-- Tony
</BLOCKQUOTE>
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<P> <A NAME="2c/26"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">About RS422</FONT></H3>
Fri, 1 Dec 2000 16:46:54 +0800
<BR>From: Elijah Pau (<a href="mailto:linux-questions-only@ssc.com?cc:e.pau@tct.com.hk">e.pau@tct.com.hk</a>)
<BLOCKQUOTE>
Hi James,
</BLOCKQUOTE>
<BLOCKQUOTE>
Stumble across you page while looking for some info on RS422 product. Sorry
to say that you may be answering the wrong question. As far as I know,
RS422 is a hardware spec. i.e., it's about how hardware talk amongst
themselves. The original question seems to be about how Linux (software)
talk to the adaptor card. The representative for the card would probably be
a UART. Identify that, and you are almost home.
</BLOCKQUOTE>
<BLOCKQUOTE>
Just my 2cents.
</BLOCKQUOTE>
<BLOCKQUOTE>
Cheers, and keep the helping out spirit going.
</BLOCKQUOTE>
<BLOCKQUOTE>
=== Elijah Pau
</BLOCKQUOTE>
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<P> <A NAME="2c/27"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">x-base languages for Linux</FONT></H3>
Mon, 04 Dec 2000 22:55:06 -0500
<BR>From: Hiram & Patti Rosenberg
<BLOCKQUOTE>
Dear Mr. Answer Guy,
</BLOCKQUOTE>
<BLOCKQUOTE>
I do not know if this is the correct venue for writing to you in
relation to the Linux Gazette column, so please do not throw any
brickbats my way. I just wanted to add one piece of knowledge to the
puzzle raised by a Michael "Mookie" Kepler's inquiry from back in 1998.
I've been programming in Recital, a 4GL xbase product that runs over our
Sun Solaris network. They have a product for Linux; I can not recall
the price but a developer kit was only a 3 digit number as I recall. I
work in the tech pubs section of a major world-class helicopter factory
and we use their Unix product as the backbone of the publication
production and illustration tracking system.
</BLOCKQUOTE>
<BLOCKQUOTE>
Recital is in Danvers, MA, just north of Boston.
</BLOCKQUOTE>
<BLOCKQUOTE>
Hi Rosenberg
</BLOCKQUOTE>
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<P> <A NAME="2c/28"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">NT Event Reporting in Unix/Linux</FONT></H3>
Fri, 1 Dec 2000 13:58:37 -0500
<BR>From: Sheldon Dubrowin
(<A HREF="mailto:linux-questions-only@ssc.com?cc:sdubrowin@ibasis.net"
>sdubrowin@ibasis.net</A>)
<BLOCKQUOTE>
I was looking for something like this also and found an article in the
September 2000 issue of SysAdmin Magazine (www.sysadminmag.com). In that
article, they talk about a Perl Script that can be run on the NT box that
will format NT Event Log messages in a syslog format and send them to a
Unix/Linux syslog server. The article is by Joe Aguiar, I haven't tried
this technique yet, but I will be looking into trying this out, just not
yet. Anyways, I thought you might be interested in this article.
</BLOCKQUOTE>
<BLOCKQUOTE>
Sheldon M Dubrowin
</BLOCKQUOTE>
<!-- end 28 -->
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<P> <A NAME="2c/29"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Need info</FONT></H3>
Tue, 12 Dec 2000 12:26:11 +0200
<BR>From: Dori Adler
<P><STRONG>
Hi
</STRONG></P>
<P><STRONG>
I don't know if this is the appropriate email address if not I'm truly
sorry.
</STRONG></P>
<P><STRONG>
Question: Is there a MS Exchange Server Emulator for Linux?
</STRONG></P>
<BLOCKQUOTE>
We were given a Tip about Tradewinds in the last month or two. Not being
Windows users ourselves, we don't know how good it is. But you can try it,
and if it works for you, you could write an article for us.
</BLOCKQUOTE>
<P><STRONG>
I need to get MS Outlook Clients with MS Exchange server Services (Only) to
connect to the linus server , do you know how <TT>/</TT> where?
</STRONG></P>
<BLOCKQUOTE>
Normal Linux mail servers are POP3 ... IMAP is a bit less common but certainly
available. So if you are more concerned about the mail than about other
Exchange features, MS Outlook should already work.
</BLOCKQUOTE>
<P><STRONG>
Thanks and sorry again
Dori
</STRONG></P>
<BLOCKQUOTE>
Best of luck -- Heather
</BLOCKQUOTE>
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<P> <A NAME="2c/31"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Fat 32 Linux instillation</FONT></H3>
Sat, 16 Dec 2000 01:25:47 -0600
<BR>From: (<a href="mailto:linux-questions-only@ssc.com?cc:tomvanberkel@mindspring.com">tomvanberkel@mindspring.com</a>)
<p><strong>
Can I install Linux on a FAT 32 partition with a dual boot configuration
including windows ME on the primary partition?
Thanks, TVB
</strong></p>
<blockquote>Yeah, there's a handful of distros aimed at living on a FAT
filesystem. You can find a bunch of them listed on Linux Weekly
News (<a href="http://www.lwn.net/">www.lwn.net</a>) - Zipslack
and PhatLinux have been around a while, with new ones like Lin4Win
popping up occasionally.
<br>-- Heather
</blockquote>
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<P> <A NAME="2c/32"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Available spcae avail on Hd!</FONT></H3>
Tue, 12 Dec 2000 09:14:44 -0800
<BR>The Chief
<P><STRONG>
Hi:Iam Newbie with Linux How do I find out how much space avail on Hd! My
system I have mandrake 7.1 installed on my 3Gig Hd!
</STRONG></P>
<BLOCKQUOTE>
The "df" command shows the amount of free space on each filesystem.
</BLOCKQUOTE>
<BLOCKQUOTE><pre>
% df
Filesystem 1k-blocks Used Available Use% Mounted on
/dev/hda5 1981000 1620129 258459 87% /
/dev/hda1 7746 5141 2205 70% /boot
</pre></BLOCKQUOTE>
<BLOCKQUOTE>
My total amount of free space is 258459 + 2205 = 260664 KB (260 MB).
</BLOCKQUOTE>
<BLOCKQUOTE>
Extra hint: to see how much space a particular directory and all its
subdirectories use, run "<tt>du</tt> DIRECTORY". This lists each subdirectory
separately and then a total at the bottom. To get just the total, run
"<TT>du -s</TT> DIRECTORY".
</BLOCKQUOTE>
<!-- end 32 -->
<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<H1><font color="maroon">Linux On Your Desktop</font></H1>
<H2><EM>- setting up GNOME -</EM></H2>
<H4>By <a href="mailto:andreiana@yahoo.com">Marius Andreiana</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<P>First of all, a Happy New Year! If you don't use Linux at home yet, you'll learn now more
about it and you will have a happier year!
</P>
<P>
Why would one use Linux on the desktop ? Isn't Linux an operating system for servers ?
It was designed for multi-user, networked environments, but it's stability pushed it on the
desktop too (if you are on the desktop, doesn't mean you can afford you can boot from time to time).
</P>
<P>
Okay than, it's stable, but you still like MS Windows because you don't want to type commands, and
MS Windows is so easy to use! Easier and more user-friendly than Linux ? Don't think so!
Sometimes I use MS Windows machines and it's quite frustrating. Illegal operations,
Explorer not responding and popups from shareware applications. No thanks! Let's give Linux a try!
</P>
<P>
Get a recent Linux distribution (I recommend <A HREF="http://www.redhat.com">Red Hat</A> Linux 7.0 or
<A HREF="http://www.debian.org">Debian</A> 2.2) and install it (see the instalation manual included for
details). You don't need to delete Windows (yet :-), just make sure you have a 1G+ partition available.
</P>
<P>
I assume at this point you have it installed Linux, created an user (during instalation) to login with (don't use
the special user <B>root</B>, which has complete powers over all system, unless you need it) and installed
the <A HREF="http://www.gnome.org">GNOME</A> desktop environment (being by far my favourite), which I'll focus on.
Remember this article expresses my personal preferences, which may not suit you.
</P>
<P>
Login at the graphical promt and let's start! If English isn't your native language, you can select yours at login
time. After logging in, you see a panel and the default desktop launchers (shortcuts).
</P>
<P>
The panel hosts the main menu, applets and launchers. You can have more panels, but we'll stick to one for now.
Applets are small applications embedded in the panel, such as task list (all open windows have buttons with their title
and icon) and clock. You can remove/add applets easily by right-clicking them or right-clicking the panel, and selecting
Panel -> Add to panel -> Applet and the applet you want. Right-click on the clock now, Remove from panel, then add
Applet -> Clocks -> After Step Clock. Right click on it again, select Move and put it where you like. Feel free to experiment
with the applets. It's nice to have the Multimedia -> Mixer applet for sound card volume.
</P>
<P>
There's also the Desk Guide applet, which shows a list of desktops. What's that ? Well, you can have more desktops, unlike
MS WIndows, where there is only one. If you open lots of applications, it's getting hard to navigate through them. I like to use
a desktop for terminals, one for editing, one for internet browsing, and so on. You can flip through them clicking in the Desk Guide
applet or pressing ALT+F1, ALT+F2, etc. (note: this is the default on the Sawfish window manager. ALT is also called Meta).
</P>
<P>
Before going to the window manager, let's work a little more on the panel. I like it clean, so I remove the After Step clock, add back
the simple clock. RIght click the panel, select Panel -> Properties -> All properties, and choose the Tiny size. Notice how
the mixer applet changed, moving to the horizontal position to fit the panel size. You can add launchers to panel, I'll let you
figure out how (no need to read the manual for that :).
</P>
<P>
The window manager manages windows (surprise!). Moving a window, the title bar and all window-related operations is its job.
Sawfish is very nice. Go to Control Center, and after experimenting with different settings, try Sawfish window manager -> Shortcuts.
(M stands for Meta, which is the ALT key). I like start Netscape by pressing Ctrl+Meta+N, instead of selecting it from the menu or
panel launcher. To do that, choose Insert, Run Shell Command, type the command (netscape) and Grab the key shortcut.
<BR>
I have lots of keyboard shortcuts, and don't use desktop launchers at all (to double click one, you need to minimize all open
windows, or move to a unused desktop). Other shortcuts I use is Ctrl+Meta+M for maximizing window, Ctrl+Meta+D to delete it
(close). Windows have gravity, meaning when you open a new window, it will be posistioned in the place where it has the most
unoccupied space available.
</P>
<P>
Some quick tips:
<UL>
<LI>You can move windows by pressing Meta, press and hold click anywhere in the window and move the mouse
<LI>To copy & paste text, select it with the mouse, then click where you want to paste it with the middle mouse button (if you don't
have one and choose to emulate a 3 button mouse, press both buttons)
<LI>To log out quickly, press Ctrl+Meta+Del (it's the default shortcut on Sawfish). Your open applications wil open again next
time you log in
<LI>To open a link in Netscape in a new window, press it with middle mouse button
</UL>.
</P>
<P>
Here is a screenshot of my desktop :
<P>
<DIV ALIGN="CENTER">
<IMG SRC="misc/andreiana/marius_desktop.jpg" WIDTH="800" HEIGHT="600" BORDER="0" ALT="Marius' Desktop"></P>
</DIV>
</P>
<P>Don't like how it looks ? Change it! Use themes, both for GTK (Gimp Toolkit, such as buttons, labels...) and Sawfish.
Visit <A HREF="http://themes.org">themes.org</A> to see more themes than included ones. Now how about this (older screenshot):
<P>
<DIV ALIGN="CENTER">
<IMG SRC="misc/andreiana/marius_desktop_startrek.jpg" WIDTH="800" HEIGHT="600" BORDER="0" ALT="Marius' Desktop - Star Trek theme">
</DIV>
</P></P>
<P>
Next, you'll see how to manage your system. If this would have been about MS Windows, I would have talked about using
several shareware anti-virus programs, using Defrag, purchasing and using Norton Utilities, provide links to several sites with
shareware software, learn to install & remove them, cleaning up after them, making backups of your registry, and tips about how
to reboot faster.
<BR>Fortunalley, this is Linux, so managing your system means installing and removing applications! :-) An application comes
usually in a package (.rpm for Red Hat, .deb for Debian). Using Red Hat Linux, I'll focus on RPM.
</P>
<P>
Open GnoRPM (Main menu -> Programs -> System). If you want to install/remove packages, you'll need to enter root password.
Look around to see what you have installed now. To find out more about a package, Query it.
<BR>
You can search for software at <A HREF="http://freshmeat.net">freshmeat</A>. For example, get the Bluefish HTML editor,
which I've used to write this article. Download it, then in GnoRPM use Install.
</P>
<P>
I update my packages quite often, software evolving pretty fast, being free open-source software. If you use Red Hat Linux 7.0,
visit <A HREF="http://www.redhat.com/support/errata/rh7-errata-bugfixes.html">
http://www.redhat.com/support/errata/rh7-errata-bugfixes.html</A> and update glibc libraries to version 2.2.
</P>
<P>
A quick note about accesing your CD-ROM : in GNOME, when you enter a CD, a file-manager window opens. What happens
it that it's also automatically mounted. To access a storage device in Linux (CD-ROM, floppy, hard-disk), you have to mount it
in a directory. There are no letters for it (like A:, C:, D: etc). The CD-ROM is mounted by default in /mnt/cdrom.
<BR>
The easiest way to use Windows-formatted floppies is with a text terminal, with commands such as <B>mdir a:</B>,
<B>mcopy file.txt a:</B>, <B>mformat a:</B>.
<BR>
Please read the distribution manual for more details.
</P>
<P>
That's it for this month. Please have a look at the Getting Started manual and GNOME manual (skim through them to see what
they talk about, and return later when you need something).
</P>
<P>
Experiment & learn more about Linux; once you get used to it,
you'll love it. Don't use root if you don't know what you do.
<P>
Keep your files organized.
I've had more partitions, but always I was running out of space on one of them, so now I have one big
partition (10G). I've created two directories in <B>/</B> : <B>/opt</B> and <B>/my</B>.
As the Linux <A HREF="http://www.pathname.com/fhs">Filesystem Hierarchy
Standard</A> says, <B>/opt</B> is reserved for the installation of add-on
application software packages; large applications, such as <A
HREF="http://www.openoffice.org">Open Office</A>, can keep all their files
together. But I also store there files already saved on CDs, like mp3s and
documentation.
<P> <B>/my</B> isn't a standard, but I've found it to be a convenient location
for files I need to save when I make backup, such as my work or documentation.
<B>/home</B> is a symlink to <B>/my/home</B>. If you have a web site or MySQL
databases, you may want to symlink <B>/var/www</B> and <B>/var/lib/mysql</B>
into <B>/my</B> as well. You'll also need to back up <B>/etc</B> and
<B>/boot</B> too. (You could symlink these into <B>/my</B> as well but you
probably shouldn't, since the machine won't boot if these directories get
erased or anything funny happens to the symlink.)
<P>To learn more, visit <A HREF="http://linuxdoc.org">linuxdoc.org</A>. There you'll find, among others, HOWTOs, short documents
which talk about a specific thing. If you want to learn more about your computer & Linux, you can! Unlike MS Windows, Linux is
an open operating system, with lots of features and documentation.
</P>
<P>Some interesting sites to visit regularily are <A HREF="http://lwn.net">Linux Weekly News</A>,
<A HREF="http://linuxtoday.com">Linux Today</A>, <A HREF="http://slashdot.org">Slashdot</A> and
<A HREF="http://freshmeat.net">Freshmeat.</A></P>
<P>
Next month we'll talk about how to play mp3s cross-fading them, divx movies and more! Until then, happy Linuxing!
</P>
</BODY>
</HTML>
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2000, Marius Andreiana.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 61 of <i>Linux Gazette</i>, January 2001</H5>
<!-- *** END copyright *** -->
<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<H1><font color="maroon">HelpDex</font></H1>
<H4>By <a href="mailto:shane_collinge@yahoo.com">Shane Collinge</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<IMG ALT="touchtype.jpg" SRC="misc/collinge/touchtype.jpg"
WIDTH="750" HEIGHT="303">
<BR CLEAR="all">
<IMG ALT="faxvoice.jpg" SRC="misc/collinge/faxvoice.jpg"
WIDTH="750" HEIGHT="303">
<BR CLEAR="all">
<IMG ALT="msmodem.jpg" SRC="misc/collinge/msmodem.jpg"
WIDTH="750" HEIGHT="303">
<BR CLEAR="all">
<IMG ALT="fiftyeight.jpg" SRC="misc/collinge/fiftyeight.jpg"
WIDTH="750" HEIGHT="303">
<BR CLEAR="all">
<IMG ALT="popular.jpg" SRC="misc/collinge/popular.jpg"
WIDTH="750" HEIGHT="303">
<BR CLEAR="all">
<IMG ALT="bzzt.jpg" SRC="misc/collinge/bzzt.jpg"
WIDTH="750" HEIGHT="303">
<BR CLEAR="all">
<IMG ALT="restored.jpg" SRC="misc/collinge/restored.jpg"
WIDTH="750" HEIGHT="303">
<BR CLEAR="all">
<IMG ALT="insidious.jpg" SRC="misc/collinge/insidious.jpg"
WIDTH="750" HEIGHT="303">
<BR CLEAR="all">
<IMG ALT="os2.jpg" SRC="misc/collinge/os2.jpg"
WIDTH="750" HEIGHT="303">
<BR CLEAR="all">
<IMG ALT="redhat7.jpg" SRC="misc/collinge/redhat7.jpg"
WIDTH="750" HEIGHT="303">
<BR CLEAR="all">
<P> Courtesy
<A HREF="http://www.linuxtoday.com/helpdex">
Linux Today</A>, where you can read all the latest <EM>Help Dex</EM> cartoons.
<BLOCKQUOTE><EM>
[Shane invites your suggestions for future HelpDex cartoons.
What do you think is funny about the Linux world? Send him your
ideas and let him expand on them. His address is
<A HREF="mailto:shane_collinge@yahoo.com">shane_collinge@yahoo.com</A>
Suggesters will be acknowledged in the cartoon unless you request not
to be. -Mike.]
</EM></BLOCKQUOTE>
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2000, Shane Collinge.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 60 of <i>Linux Gazette</i>, December 2000</H5>
<!-- *** END copyright *** -->
<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<H1><font color="maroon">Using ssh</font></H1>
<H4>By <a href="mailto:dellomodarme">Matteo Dell'Omodarme</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<P>Every time we telnet into a remote machine the
connection data will cross the local network, giving an eventual
intruder the possibility to spy the connection and eventually insert
some malicious commands into the data flux. The use of some strong
cryptography systems will allow an enormous improvement in the security
of the net.
<P>From the manual page of ssh we can learn that: "Ssh
(Secure Shell) is a program for logging into a remote machine and
executing commands in a remote machine. It is intended to replace
rlogin and rsh, and provide secure encrypted communications between
two untrusted hosts over an insecure network. X11 connections and
arbitrary TCP/IP ports can also be forwarded over the secure
channel". It is a powerful, very easy-to-use program that uses
strong cryptography for protecting all transmitted confidential data,
including passwords.
<P> At present time there are two SSH protocol, referred
as SSH2 and SSH1, the first one being an improvement of the SSH1
protocol. SSH2 now supports other key-exchange methods besides
double-encrypting RSA key exchange. The current distribution comes
with Diffie-Hellman key exchange and has support for DSA and other
public key algorithms besides RSA.
<P>SSH2 can be compatible with SSH1, but it is not
compatible by default; the SSH2 server alone can't manage a SSH1
connection and a SSH1 server must be in place in order to do that.
<h1 align=center>Obtaining and installing SSH</h1>
<P>You can obtain SSH2 & SSH1 clients and servers from
the <a href="http://www.ssh.com"> master FTP server</a>, or from its
mirrors. The last version of SSH1 protocol is ssh-1.2.30.tar.gz,
while for SSH2 you can download ssh-2.3.0.tar.gz.
<P>The installation process is really easy. The first
step is unpack your SSH1 sources:
<pre>
tar -zxf ssh-1.2.30.tar.gz
</pre>
<P>This will create a directory ssh-1.2.30. Now go into
that directory and start the configuration process:
<pre>
cd ssh-1.2.30
./configure
</pre>
<P>The <em>configure</em> script carries out all the
configuration needed in the compiling stage, searching the system for
the required library and programs. When the scripts end its job you
can start the compilation:
<pre>
make
</pre>
<P>After the compilation stage, become super-user and
install binaries, configuration files, and hostkey by typing:
<pre>
make install
</pre>
<P>This will normally install clients (scp1, ssh-add1,
ssh-agent1, ssh-askpass1, ssh-keygen1, ssh1) to /usr/local/bin, and a
server (sshd1) to /usr/local/sbin. Notice that, in /usr/local/bin
there are also symbolic link (without the trailing "1") to the real
executables.
<P>The next step is to install SSH2. The operations
needed are the same required by SSH1:
<pre>
tar -zxf ssh-2.3.0.tar.gz cd ssh-2.3.0 ./configure make
</pre>
and as a super-user:
<pre>
make install
</pre>
<h3 align=center>Compatibility SSH1 - SSH2</h3>
<P>In the following part we suppose you have either SSH1
and SSH2 installed.<br> In order to make the SSH2 server able to
manage a SSH1 connection you should edit SSH2's configuration files,
which are normally placed in the directory /etc/ssh2/.<br> In that
directory edit the file <em>sshd2_config</em>, the configuration file
for sshd2 (Secure Shell Daemon) which is the daemon program for
ssh2. Add the lines:
<pre>
Ssh1Compatibility yes Sshd1Path /usr/local/sbin/sshd1
</pre>
<P>Obviously modify the information
/usr/local/sbin/sshd1 to agree with your sshd1 installation directory.
With this configuration, sshd2 server will forward requests from SSH1
client to sshd1.
<P>Then add two lines to the file <em>ssh2_config</em>,
placed in the same directory:
<pre>
Ssh1Compatibility yes Ssh1Path /usr/local/bin/ssh1
</pre>
<P>now ssh2 client will invoke ssh1 client when
contacting a SSH1 server.
<h1 align=center>Starting SSH</h1>
<P>There are mainly two different techniques to start
sshd at boot time.
<ul>
<li ><P> Go into /etc/rc.d directory, and edit the file
<em>rc.local</em>. At its end add the lines:
<pre>
echo "Starting sshd ...." /usr/local/sbin/sshd
</pre>
<P>In such a way, at the end of your next computer
reboot, sshd is invoked and the message <em>Starting sshd ....</em> is
printed on the screen. To start sshd without rebooting the machine
type from the command line:
<pre>
/usr/local/sbin/sshd
</pre>
<li> Alternatively, in systems using System V
initialization, you can put the <em>sshd2.startup</em> script,
which came with this distribution, to /etc/rc.d/init.d, naming it
sshd2. Then go to rc$number.d directory, where $number is your
default runlevel. If you don't know your runlevel search in the
file /etc/inittab the line specifying it:
<pre>
id:5:initdefault
</pre>
or
<pre>
id:3:initdefault
</pre>
In the first case your runlevel is 5, in the second one it is 3.
<P>In the directory rc$number.d issue the command:
<pre>
ln -s ../init.d/sshd2 S90sshd2
</pre>
Then change directory to /etc/rc.d/rc0.d and run the command:
<pre>
ln -s ../init.d/sshd2 K90sshd2
</pre>
Repeat the operation in the directory /etc/rc.d/rc6.d.
<P>After doing that you can start sshd2 with out
rebooting the machine, simply running the script:
<pre>
/etc/rc.d/init.d/sshd2 start
</pre>
</ul>
<h1 align=center>Establish a SSH connection</h1>
<P>Once sshd is running on your machine you can test
your configuration trying to login into it using the ssh client. Let's
suppose that you machine is named <em>host1</em> and your login name
is <em>myname</em>. To start a ssh connection use the command:
<pre>
ssh -l myname host1
</pre>
<P>In such a way ssh2 client (default client) tries to
connect to <em>host1</em> port 22 (default port). sshd2 daemon,
running on <em>host1</em>, catches the request and asks for the
<em>myname</em> password. If the password is correct it allows the
login and open a shell.
<h3 align=center>Generating and managing ssh keys</h3>
<P>Ssh allows another authentication mechanism, based
upon <em>authentication keys</em>, a public key cryptography
method. Each user wishing to use ssh with public key authentication
must runs <em>ssh-keygen</em> command (without any option) to create
authentication keys. The command starts the generation of the keys
pair (public and private) and ask for a passphrase in order to protect
them.<br> Two file are created in the $HOME/.ssh2/
directory: <em>id_dsa_1024_a</em> and <em>id_dsa_1024_a.pub</em>, the
user private and public key.
<P>Let's suppose that we have two accounts, <em>myname1</em> on
<em>host1</em> and <em>myname2</em> on <em>host2</em>. We want to login
from host1 to host2 using ssh public key authentication. In order to do that
four steps are required:
<ol type=1>
<li> On host1 generate the key pair using ssh-keygen
command, and choose a passphrase to protect it.<p>
<li> Login into host2, using ssh password
authentication, and repeat the previous operation. Then change
directory to $HOME/.ssh2 and create a file, named
<em>identification</em>, containing the following lines:
<pre>
# identification
IdKey id_dsa_1024_a
</pre>
<P>This file is used by sshd to identify the key pair to
be used during connections.<p>
<li> <P>From host2, get the ssh host1 public key and
rename it in a suitable way (e.g. <em>host1.pub</em>):
<pre>
ftp host1
[...]
cd .ssh2
get id_dsa_1024_a.pub host1.pub
</pre>
<P>At the end of ftp process a copy of host1 public key,
named <em>host1.pub</em>, resides in host2 $HOME/.ssh2 directory.<p>
<li> Create the file <em>authorization</em>
containing the following lines:
<pre>
# authorization
Key host1.pub
</pre>
<P>This file lists all trusted ssh public keys placed in
$HOME/.ssh2 directory. When a ssh connection is started from a user
whom public key matches one of the entry of <em>authorization</em>
file the public key authentication scheme starts.
</ol>
<P>In order to test the previous configuration, you
could try to connect from host1 to host2 using ssh. Sshd must reply
asking for a passphrase, otherwise, if password is requested, some
mistakes occurred in the configuration process and you must check
carefully steps 1 to 4.<br>
The passphrase required is your LOCAL passphrase (i.e. passphrase
protecting host1 public key).
<h1 align=center>Coming next...</h1>
<P>The next article will present other programs and facilities
from ssh suite: ssh-agent and ssh-add (two useful
passphrase management programs), and sftp and scp (a secure
way to transfer files across the net).
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2000, Matteo Dell'Omodarme.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 61 of <i>Linux Gazette</i>, January 2001</H5>
<!-- *** END copyright *** -->
<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<H1><font color="maroon">The emelfm File Manager</font></H1>
<H4>By <a href="mailto:pevans@catholic.org">Paul Evans</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<img src="misc/evans/emelfm.jpg" width="320" height="213" border="1" alt="emelfm full screen" align="right" hspace="20" vspace="20">
<p>After migrating from the Amiga to the original Slackware distribution of Linux, I spent several years searching out a replacement for Directory Opus.
Now, a 'file manager' means different things to different people. Some simply want to copy, move, rename files etc. Others want to be able to operate
on those files in esoteric ways. At whim. Configurably. As you may have guessed, I'm one of the latter.</p>
<p>I tried everything that came along, whether they claimed to be clones of Dopus or just great file managers. All fell short in some way. Some were too slow,
others were fast, but not configurable enough. Still others had both, but configuring them was difficult.</p>
<p>In the mean time, I used the venerable Midnight Commander (good ol' mc). You can do anything with mc - you just have to configure it, but it's still console
based and a lot of basic operations are more easily done from a gui. New problem: after six years of using mc, I had added the desire for a Linux Dopus that behaved like
mc. Great. Now I wanted superb keyboard navigation <i>and</i> key-mapping <i>and</i> mousing <i>and</i> configurable button banks. Prospects were looking pretty grim</p>
<p>And then <a href="mailto:macst92@imap.pitt.edu">Michael Clark</a> came along and wrote <A HREF="http://www.pitt.edu/~macst92/emelfm/">emelfm</A>.</p>
<p>emelfm has <b><i>all these</i></b> - and more.</p>
<BR CLEAR="all">
<H2>Overview</H2>
<img src="misc/evans/emelfm_context.jpg" width="431" height="254" border="1" alt="an emelfm context menu" align="right" hspace="20" vspace="20">
<p>As a graphical file manager, emelfm has no peer. Any file operation imaginable may be carried out using emelfm. It has all the functionality of a modern
gui based file manager, yet at the same time mirrors the functionality of mc, including the ctrl+o shell. In addition, emelfm allows you to easily construct shell scripts
of a few lines and put them on a button - or in a context menu. Yes, you could put these in a shell script or an alias (and, of course, you still can), but there's
something just so <i>very nice</i> about drag-selecting a few files and then clicking one button which performs magic on them. </p>
<p>I'm always a little at a loss when the "GUI vs. Console" wars break out. I like and use both <i>when I find it appropriate</i>. Thus far, there is no simple, intuitive
way to provide point and click access to all the power the command line has to offer and I'm the first to dive in there when the need arises (or even just for sport).
Now then, just suppose I'd delved into the manual for mpage and written 'mpage -P -m50lb20t20r -j 1%2'. Yes, I needed the command line. Yes, it's very useful
to me. No, I won't remember it past my next cup of tea. Solution: add it to the context menu for .txt files in emelfm - or put it on a button. The above example is
quite trivial compared to what's really possible with emelfm. It simply serves to underline the point that emelfm actually bridges between your work on the command line
and your use of the gui. </p>
<BR CLEAR="all">
<img src="misc/evans/example_foo.jpg" width="268" height="247" alt="one of emelfm's file-type dialogs" align="left" hspace="20" vspace="20">
<p>Nearly all gui file managers allow for some default action when you double-click on a file. emelfm goes beyond that. If you right click over the same file you'll be
able to select from a list of <i>alternative</i> actions. Two things to note: 1) you've got more options and 2) it's context sensitive, i.e. you only see choices related
to that particular file-type. For example, in my own case, if I were to double-click an htm,html,shtm or shtml file I would be reading it in kless via w3m. However,
if I right click the same file a whole range of options open up to me. As if that's not enough, there's always the "open with" item, so I can type in a command on
the fly.</p>
<p>Also included in the emelfm repertoire are a 'vfs' for diving into tarballs and zip files, a pack plugin for making archives (with an elegant, intuitive interface),
an easy to use 'for each', a rename by extension (pattern really - much better) and many more.</p>
<p>Here's some other stuff in no particular order:</p>
<UL>
<LI>very simple configuration for unknown file-types
<LI>configurable coloured highlighting of file types
<LI>drag and drop internally and between other gtk apps
<LI>configurable fonts
<LI>plugins and a reference manual for writing your own
<LI>one-click access to your home directory
<LI>cloning of a file to the same dir under a different name
<LI>verbose file listings
<LI>various sorting methods via a single click
<LI>bookmarks
<LI>default startup dirs
<LI>capture of command output
<LI>more. I forget till I need it.....
</UL>
<BR CLEAR="all">
<H2>Installation</H2>
Even if you've never compiled a program before, emelfm will be trivial to compile.<br><br>
<UL>
<LI>Download the tarball and unpack it somewhere.<br>
<LI>Pop a shell and cd into the same directory and type 'make'.<br>
<LI>Then 'su' to root and type 'make install'.<br><br>
</UL>
You're done! Ctrl+d to get out of root and run emelfm by typing its name. That's all there is to it.<br>
Now, you can make an icon for emelfm or add it to your menu structure. It happens that I use KDE, so I used khotkeys and assigned emelfm to ctrl+esc for quick access.<br>
<H2>Navigation</H2>
<p>As detailed above, part of our shopping list was keyboard navigation and emelfm works out of the box. Up and down cursor keys respond predictably. Left cursor moves you up a directory and right cursor on a directory moves you down into that directory. Tab or space will toggle the active pane. Return or right arrow on a file will run the default command on that file.</p>
<p>If you press the shift key while moving up or down, you will highlight a range of files. Like mc, you can also use the 'insert' key to tag files.</p>
<p><a href="emelfm_keys.txt">Here's</a> a list of default keybindings. These are just a beginning. You can easily map all the default mc keys into emelfm. Then add all your own personal keybindings. As you can see by the screen shot, the configuration is pretty paul-proof.</p>
<img src="misc/evans/emelfm_keys.jpg" width="524" height="310" border="1" alt="emelfm keys dialog" hspace="20" vspace="20">
<p>Of course, navigating with the mouse is the same as the keyboard and it's intuitive enough that I don't feel I need to go into it. Double-clicking performs the
default action and Ctrl+click allows spot selection etcetera. One thing I need to mention is that 'drag and drop' is performed using the <i>middle</i> mouse button.</p>
<BR CLEAR="all">
<H2>Usage</H2>
<p>Where do I begin? You can configure everything from the key bindings to what's shown in the columns.
There are so many ways to configure emelfm,
I'll just give you a few thoughts:</p>
<UL>
<LI>Some misc. tips available from the readme are <a href="misc/evans/emelfm_tricks.txt">here.</a>
<LI>configure a button like 'kdesu -c emelfm'. We all su to root sometimes. We have to... Now, tell emelfm to show dirs in red, that way you'll know you're running as root. Also, resist changing the default config for root's emelfm - the less at home you are the better and - the sooner you'll leave.
<LI>Make a button for xterm as root and another for xterm as user. The nice part is they alway open in the target directory
<LI>Almost completely unrelated timesavers: create aliases for cf='./configure', mk='make' and only in root, mi='make install'
<LI>both df and du work nicer with the '-h' (human) option
<LI>Read the whole <a href="misc/evans/emelfm_readme.txt">Readme</a> it's worth it!
</UL>
<H2>Summary</H2>
<p>This program is not only the equal of 'Dopus' it's actually better. Before you flame me, I used Amigas since 1986 and
had thousands of lines of rexx hanging off of dopus. Now I have (so far)
a few hundred lines of perl and bash hanging off of emelfm. That, and a lot of ELF binaries. </p>
<p>No single program pleases everyone, but I know both ex-Amigoids and new Penguinistas who have and use emelfm.
If you're looking for something that most resembles Dopus visually, you should try
<A HREF="http://www.informatik.uni-halle.de/~hoffmanr/worker-e.html">Worker</A> by Ralf Hoffmann. There's also an article
about "Worker" <A HREF="http://www.canadacomputes.com/v3/story/1,1017,4954,00.html?tag=81&amp;sb=79">here</A>.
For a reliance on file magic give <A HREF="http://www.obsession.se/gentoo/">gentoo</A> by Emil Brink a download. For built-in ftp,
Henrik Harmsen wrote <A HREF="http://www.cd.chalmers.se/~hch/filerunner.html">filerunner</A>. I think emelfm probably owes the most
to "filerunner" in terms of look and feel.
</p>
<H4>Wish list</H4>
<UL>
<LI>Right-click alternatives and "dog-ears" for command buttons
<LI>du of selected files
<LI>Colouring of buttons etc.
<LI>CD-RW plugin
<LI>ftp
</UL>
<p>I know the author is seriously considering at least the first four.
</p>
<p>In sum, it's guys like Michael Clark that keep guys like me from having to learn 'C'. :-)</p>
<p>You will find Mr. Clark both helpfull and responsive to bug reports and requests for features.</p>
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2000, Paul Evans.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 61 of <i>Linux Gazette</i>, January 2001</H5>
<!-- *** END copyright *** -->
<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<H1><font color="maroon">Tuxedo Tails</font></H1>
<H4>By <a href="mailto:kasten@sunpuppy.com">Eric Kasten</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<IMG ALT="holiday.png" SRC="misc/kasten/holiday.png"
WIDTH="370" HEIGHT="510">
<HR NOSHADE WIDTH="80%" ALIGN="center">
<IMG ALT="servdali.png" SRC="misc/kasten/servdali.png"
WIDTH="370" HEIGHT="510">
<BR CLEAR="all">
<BLOCKQUOTE><EM>
[Eric also draws the <I>Sun Puppy</I> comic strip at
<A HREF="http://www.sunpuppy.com">http://www.sunpuppy.com</A>. -Ed.]
</EM></BLOCKQUOTE>
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2000, Eric Kasten.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 60 of <i>Linux Gazette</i>, December 2000</H5>
<!-- *** END copyright *** -->
<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<H1><font color="maroon">Using the Wireless Modem Ricochet</font></H1>
<H4>By <a href="mailto:python@kepnet.com">Mark Nielsen</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<ol>
<li>
<a href="#REF">References</a></li>
<li>
<a href="#Introduction">Introduction</a></li>
<li>
<a href="#getting">Getting Ricochet</a></li>
<li>
<a href="#install">Installing the Ricochet modem</a></li>
<li>
<a href="#firewall">Setting up a firewall for your network</a></li>
<li>
<a href="#Why">Why use the Ricochet modem?</a></li>
<li>
<a href="#Conclusion">Conclusion</a></li>
</ol>
<h3>
<a NAME="REF"></a>References</h3>
<ol>
<li><a href="http://phobos.illtel.denver.co.us/~abelits/metricom/">Metricom modems support in Linux</a>.
This is the only place I found that explained how to install the faster modems.</li>
<li>
<li> If this article changes, it will
<a href="http://www.gnujobs.com/Articles/11/Ricochet.html">available at GNUJobs.com</a>.
<li><a href="../lg_index.html"> LG index</a> which has many
articles on networking and firewalls. You may also want to look at <a href="http://www.linux.org/docs/index.html">Linux.org</a>
to find documentation on how to setup a firewall.
</ol>
<h3>
<a NAME="Introduction"></a>Introduction</h3>
The Ricochet modems are wireless modems that let you connect your computer
to the internet through an ISP provider that is hooked up to the
wireless network. It is only available in
<a href="http://www.ricochet.com/about_us/coverage_maps/index.html">certain areas</a>.
<p>
None of the ISPs support Linux. They officially only support crappy
horrible operating systems are not good for a technical person or
a real programmer. Naturally, Linux, FreeBSD, and other good quality
operating systems are ignored. It makes sense from profit point of view.
Call the ISPs and let me know you want them to support real operating systems.
<p>
The modems will connect at 80 Kbps with a serial port and 128 Kbps for a USB
connection. I only use the serial port connection, for now, and it seems
faster and more stable compared to a normal dial-up over the phone. Sometimes
it crawls, but overall, I am very happy with the modem.
<h3>
<a NAME="getting"></a>Getting Ricochet</h3>
None of the ISPs support Linux. <a href="http://www.wwc.com">Wireless Web Connect</a>
seems to be more liberal, so I choose them. All the other service providers
seemed to have staff that had no clue what Linux was and they had a big
corporate feel, which I usually try to avoid. I bought my modem through
the service provider for around $100, which apparently was a special price,
but I have noticed that special prices tend to become the normal prices
over time in the ISP market.
<h3>
<a NAME="install"></a>Installing the Ricochet modem</h3>
Installing the modem was really easy after I found the right webpage.
<a href="http://phobos.illtel.denver.co.us/~abelits/metricom/">Metricom modems support in Linux</a>.
<p>
It was this simple on a RedHat 6.2 system (when am I going to switch to Debian for good?),
<ol>
<li> Start the control panel with the command "control-panel" in Xwindows.
<li> Click on the Network Configurator.
<li> Click on the "Interfaces" button.
<li> Click "Add".
<li> Choose the PPP option and continue.
<li> Type in "3333" for the phone number, and the username and password. Select
the PAP option.
<li> After you have added the ppp interface, click on the interface, click
on the Edit button and type in "noipdefault" where it says "PPP Options".
Then click on "Done".
<li> Save and quit the control-panel.
</ol>
Now you need to follow the specific instructions the above article talks about.
You need to modify /etc/resolv.conf for the DNS and edit /etc/ppp/pap-secrets as described
in the article.
<p>
Overall, it was simple once I knew what to do.
<p>
If you have tried to figure out how to setup the modem, and you cannot,
and you have read this article and the other article mentioned above, then
send email to <a href="mailto:articles@gnujobs.com"> GNUJobs.com at
articles@gnujobs.com</a> and perhaps I can point you in the right direction.
If you attend the
<a href="http://www.svlug.org">SVLUG</a> meetings in the Bay Area, bring your laptop and send
me email when you are attending the next meeting, and I can help out.
<h3>
<a NAME="firewall"></a>Setting up a firewall for your network</h3>
I have a desktop computer and a laptop. I don't like using the touchpad on my
laptop, and since I have to use the serial port for my external mouse, I can't
use the Ricochet modem (unless I use the touchpad). Thus, I use my desktop
computer as a firewall. I connect
the desktop computer and laptop to a 100 mbit hub. Then I connect the Ricochet modem
to the desktop computer.
<p>
The desktop becomes my firewall. I don't have any services running on it
except for ssh. All the other ports are closed. Please use the program
<a href="http://www.insecure.org/nmap/">nmap</a> to
scan your computers to find out which ports are open. I would also disable
the root account from logging in with ssh.
<p>
If you wish to know how to setup a firewall, I 9have written many old articles
for the Linux Gazette about networking and firewalls. There are lots of resources
out there. Try linux.org also with their HOWTOS.
<h3>
<a NAME="Why"></a>Why do this stuff?</h3>
As an independent consultant, having the ability to go anywhere and
be connected is nice. Not having to pay startup costs every time you want
to get a 2nd phone line in an apartment is nice. I really loathe the local
phone companies for hitting businesses with high phone bills. The wireless
modem ends up paying for itself after you combine a phone bill and an ISP bill.
<p>
It isn't super fast, but for my needs it is just fine. I am still going to get
a DSL hookup. This will provide me with two alternate ways of connecting to
the internet should one route die for a day. That can be very bad for an
independent consultant, so two routes are a must.
<p>
I leave the modem on all day and the firewall on all day. It is nice
that it doesn't tie up a phone line and it is also nice that I don't have
wires all over the place. When I had to move to a different room because
the guy who was assembling my furniture kicked me out of my office, it was
nice that I could take the laptop with the Ricochet modem to another room.
<h3>
<a NAME="Conclusion"></a>Conclusion</h3>
The Ricochet modem is good for connecting to the internet and is a must
for a traveling independent consultant. I don't work for or get paid by
Ricochet or the service providers for Ricochet, so my opinion isn't skewed.
It is easy to setup, with just a few modifications. If you cannot afford
it as a business expense, don't do it and get a DSL line instead for
personal use because it is not going to be as fast as DSL and it can be more
expensive than DSL. There are bonuses and negatives to getting the Ricochet modem.
If we ever get to the point where the speed gets upto 500 Kbps, then DSL
has no real advantage for me (except in the Bay Area getting a fixed ip address
with DSL seems to be $30 more a month which is a lot cheaper than what I paid
for to get a fixed ip address using Cable Modems in Columbus, Ohio).
<P>
<i> Mark works as an independent consultant donating time to causes like
GNUJobs.com, writing articles, and writing free software.</i>
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2000, Mark Nielsen.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 61 of <i>Linux Gazette</i>, January 2001</H5>
<!-- *** END copyright *** -->
<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<H1><font color="maroon">When Apache Redirect Doesn't Work the First Time</font></H1>
<H4>By <a href="mailto:python@kepnet.com">Mark Nielsen</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<p><!-- END header -->
<ol>
<li>
<a href="#REF">References</a></li>
<li>
<a href="#Introduction">Introduction</a></li>
<li>
<a href="#problem">The Problem with Redirect</a></li>
<li>
<a href="#perl">Using a Perl script</a></li>
<li>
<a href="#rewrite">Using the mod_rewrite module for Apache</a></li>
<li>
<a href="#redirect">Using Redirect with Virtual Host</a></li>
<li>
<a href="#Conclusion">Conclusion</a></li>
</ol>
<h3>
<a NAME="REF"></a>References</h3>
<ul>
<li><a href="http://httpd.apache.org/"> Apache webserver</a></li>
<li> <a href="http://httpd.apache.org/docs/mod/mod_rewrite.html">Module mod_rewrite
URL Rewriting Engine</a></li>
<li> <a href="http://www.perl.com">Perl programming language</a>
<li><a href="http://www.gnujobs.com/Articles/">Mark's other articles</a>
<li><a href="http://perl.apache.org/">The Apache/Perl Integration Project</a>
</ol>
<h3>
<a NAME="Introduction"></a>Introduction</h3>
Apache has been a growing project for many years. It is personally
amazing to me how Apache is so powerful, flexible, and easy to configure for
a programmer. There is so much documentation about how to configure and do
things in Apache, other commercial webservers just can't compare. Apache
makes webserving fun for programmers. There are a lot of things you can test
and tinker with.
<p>
Along with the growing, comes new ways of doing things without getting rid
of the old ways of doing things. I have a problem with my computer at
<A HREF="http://gnujobs.com">gnujobs.com</A>.
Basically, I need to forward every request for 'http://www.tcu-inc.com/mark/articles'
to 'http://www.gnujobs.com/Articles'. I tried the Apache
<a href="http://httpd.apache.org/docs/mod/mod_alias.html#redirect">
Redirect directive</a>, but it didn't work. So, I had to figure out why it didn't work
and to see if there was any way around it.
<h3>
<a NAME="problem"></a>The Problem with Redirect</h3>
The problem is, 'Redirect' didn't work for me when I tried to forward
'http://www.tcu-inc.com/mark/articles' to 'http://www.gnujobs.com/Articles'
since both websites where running on the same webserver. However, I found out
later, and it was obvious when I thought about it twice,
I was using Redirect incorrectly. Nevertheless, it set me on a trip to
get reacquainted with mod_rewrite. The solutions I had were
<ol>
<li> Use a Perl script.</li>
<li>Use mod_rewrite with Virtual Host</li>
<li>Correctly use Redirect with Virtual Host</li>
</ol>
<h3>
<a NAME="perl"></a>Using a Perl script with Virtual Host</h3>
This was my first solution after I couldn't get Redirect to work right.
The only reason why I used it was because it was quick and dirty. It is
actually fairly complex because you have to understand Perl programming,
what "Location" does, and how to get a Perl script to execute with your
Apache webserver. Besides that, it was simple for me to do because I have
done similar things a million times over.
<p>
The nice thing about using a Perl script, is that you don't have to
recompile the Apache server. You do have to change the configuration slightly.
You don't have to install mod_perl, but if you do, the configuration
can be slightly different if you want to cache the perl script.
Also, this can be done is any programming language, not just Perl.
<p>
I had to change the httpd.conf file slightly:
<pre>
&lt;VirtualHost 206.21.120.103&gt;
ServerAdmin info@gnujobs.com
ServerName www.tcu-inc.com
DocumentRoot /www/htdocs/
ScriptAlias /mark/articles "/www2/TCU.pl"
&lt;/VirtualHost&gt;
</pre>
<p>
The ScriptAlias is the key part here.
It redirects all requests from /mark/articles
to the TCU.pl perl script.
<p>
And the perl script looked like this,
<pre>
#!/usr/bin/perl
print "Location: http://www.gnujobs.com$ENV{'REQUEST_URI'}";
</pre>
$ENV{'REQUEST_URI'} is the key part here. It is an environment
variable that is equal to the file asked for
on the www.tcu-inc.com webserver. The perl script takes the file asked for, and
then redirects the browser to the new website.
Also, I did a "chmod 755 TCU.pl" on the perl script to make sure it was
executable.
<p>
<h3>
<a NAME="rewrite"></a>Using the mod_rewrite module for Apache</h3>
Aaron Bush from <a href="http://www.colug.net">COLUG</a> is responsible for
getting me to do it in mod_rewrite. I didn't like my Perl solution, and knew
I could use mod_rewrite to do it, but I was being lazy.
I knew I should do it in mod_rewrite,
and Aaron asked me "Why don't you use mod_rewrite?".
Feeling lazy, I was
unhappy, for I knew that what separates the men from the boys can be
issues like this, so I said to myself "screw it, I haven't used mod_rewrite
in a long time, let me do it the right way".
<p>
You have to have mod_rewrite compiled into Apache in order to
use this option. Mod_rewrite is a nice module that
"provides a rule-based rewriting engine to rewrite requested URLs on the fly".
It is a very powerful module, and is essential to learn if you want to become a true
webmaster or web programmer. It is not essential that you use it, but that
you know what it can do so that you can present the options to your boss
when you want to do weird things with your webserver.
<p>
I compiled mod_rewrite into Apache and applied this configuration option
to httpd.conf.
<pre>
&lt;VirtualHost 206.21.120.103&gt;
ServerAdmin info@gnujobs.com
ServerName www.tcu-inc.com
DocumentRoot /www/htdocs/
RewriteEngine on
RewriteCond %{HTTP_HOST} ^www\.tcu\-inc\.com$
RewriteRule ^(/articles)(.*) http://www.gnujobs.com/Articles$2 [R]
&lt;/VirtualHost&gt;
</pre>
RewriteCond sets the condition for which we are going to use mod_rewrite, which
basically says pay attention to the webserver if www.tcu-inc.com is the base
website name being used. RewriteRule takes the conditions (everything at www.tcu-inc.com)
and says that if the requested file starts with "/articles" redirect it to
www.gnujobs.com. The "$2" corresponds to "(.*)". The rest
of the requested file after "/articles" is equal to "(.*)". [R] means "Take this
match and redirect it".
<h3>
<a NAME="redirect"></a>Using Redirect with Virtual Host</h3>
After I figured out how to redirect www.tcu-inc.com to gnujobs.com with
the other two methods, I realized
I was doing a mistake with the standard "Redirect". I wasn't putting the
Redirect command into the VirtualHost section. Once I did that, it worked fine.
<pre>
&lt;VirtualHost 206.21.120.103&gt;
ServerAdmin info@gnujobs.com
ServerName www.tcu-inc.com
DocumentRoot /www/htdocs/
Redirect /mark/articles http://www.gnujobs.com/Articles
&lt;/VirtualHost&gt;
</pre>
<h3>
<a NAME="Conclusion"></a>Conclusion</h3>
I did a lot of work for nothing, but I made this nice article explaining different
options for other people to learn from. Here are my suggestions about which of these
3 methods you should use:
<ol>
<li> If you don't forsee ever having programmers work on your website, use
the standard Redirect command.</li>
<li> If you are a programmer or a true webmaster, then please use mod_rewrite.
If you standardize on using mod_rewrite, you might find other uses for it as well
which you might not realize unless you have had previous practice with mod_rewrite. </li>
<li> I don't know why you would want to use a Perl script to do this, unless you
want to record certain stats (which are possible in other ways) or do something
else that is weird. Using a Perl script would just add more overhead. If you
used it with mod_perl, you might end up using more memory because of caching.
I wouldn't use a Perl script to do this, although that was my first working
solution. Bad solutions are good only in the fact that you at least have
something working.
</ol>
<i> Mark works as an independent consultant donating time to causes like
<A HREF="http://GNUJobs.com">GNUJobs.com</A>, writing articles, and writing
free software.</i>
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2000, Mark Nielsen.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 61 of <i>Linux Gazette</i>, January 2001</H5>
<!-- *** END copyright *** -->
<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<H1><font color="maroon">Learning Perl, part 1</font></H1>
<H4>By <a href="mailto:ben-fuzzybear@yahoo.com">Ben Okopnik</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<p>If you've been using Linux for any length of time, you've surely heard
of Perl; probably even run a number of scripts, perhaps without even knowing
it. Programs like "inews", "mirror", "debconf", "majordomo", "sirc", and
a host of others are written purely in Perl. Taking a quick "zgrep" through
the "Packages.gz" file in the Debian distro tells me that 382 of the packages
depend on Perl (meaning that a critical part of that package is written
in it), and 28 other packages either suggest or recommend it.
<br>&nbsp;
<p><b>So, What's It Good For?</b>
<p><tt>"Perl is great at text-processing, and it's great at tying and integrating
things together. To a scripting language, all those different elements
look the same."</tt>
<br><b><tt><font size=-1>&nbsp;-- John Ousterhout, author of the Tcl scripting
language</font></tt></b>
<p>"Perl" is supposed to stand for the "Practical Extraction and Report
Language". Right: bo-oring, but I guess that's what you've got to have
if you're going to convince $HUMONGOUS_CORP to use it. Actually, Larry
Wall <tt>&lt;larry@wall.org&gt;</tt> (the author of Perl) says in the Perl
man page: "Perl actually stands for Pathologically Eclectic Rubbish Lister,
but don't tell anyone I said that." Umm... OK, Larry. Not a word out of
me.
<p>Perl has been variously referred to as "A scripting language with delusions
of full language-hood", "The Swiss Army Chainsaw of Unix", "The duct tape
of the Web", and other equally, umm, complimentary names. It has been used
to write single-line scripts, fast-executing programs, large projects (Amazon.com's
entire editorial production and control system, Netscape's content management
and delivery system, the Human Genome Project's DNA sequencing and project
management, etc.), and millions of quick programs that do an amazing variety
of things.&nbsp; Perl can also emulate a number of common Unix system utilities
(hint: if you're looking at having to learn 'awk', 'sed', 'grep', and 'tr',
I'd suggest starting in on Perl, instead. All the functionality, much faster,
and you'll never outgrow the capabilities. Sure wish I'd known that, way
back when...)
<p>As you would expect of any modern language, Perl allows you to do object-oriented
programming. It also handles networking (sockets, etc.), is highly portable
(a well-written script will run on Linux, BSD, Solaris, DOS, Win9x, NT,
MacOS, OS/2, AmigaOS, VMS, etc. without modification), and has a very short
write/debug cycle - since there's no compilation required, you just write
the changes and run the script. There's a tremendous wealth of modules
(pre-built Perl routines) available to perform just about any task; the
Comprehensive Perl Archive Network (CPAN) is one of the best resources
a Perl programmer can have.
<br>&nbsp;
<p><b>Yeah, But What Is It <u>Really</u>?</b>
<p>Good question. I hope that, after using it for a year or so, <b>you</b>
can tell <b>me</b>. A description of anything is a container... and I'm
still trying to find one big enough to fit Perl (preferably one with a
strong lockable lid.)
<br>&nbsp;
<p><b>What Kind Of Things <u>Isn't</u> Perl Good For?</b>
<p>Hmmm. I wouldn't set out to write a GUI word processor, a video game,
or a graphic browser in it. Perl can indeed do glitzy front ends via its
interfaces to many other languages, so you <u>could</u> do all of those
things - but in my opinion, there are more efficient ways to do them in
other languages. "To a man with a hammer, every problem looks like a nail"
- let the programmer beware!
<p>Note, also, that Perl itself isn't written in Perl; neither is the Linux
kernel. Low-level stuff of that sort is best left to C/C++ with some assembler
thrown in; 'the right tools for the right job' should be every programmer's
motto.
<br>&nbsp;
<p><b>One Final Warning Before Pulling The Ripcord</b>
<p>If you know a bit of Perl, and see something in this series that 'Aint
The Way I Larned It', just remember Perl's motto: There's More Than One
Way To Do It. Usually abbreviated TMTOWDI, and pronounced "tim-today",
it is a core philosophy of Perl. Of course, corrections of any obvious
errors are welcome.
<p>
<p>Those of you who read my earlier series on shell scripting may remember
that a script starts out with the so-called "hash-bang" or "shebang" line:
<p><tt>#! /bin/bash</tt>
<p>This tells the shell to spawn a subshell in which the following code
will be executed by the specified program. This is also what's needed for
Perl scripts - the first line must be
<p><tt>#! /usr/bin/perl</tt>
<p>or whatever is the correct path to your "perl" executable.
<p>Note the requirements for a hash-bang:
<p><b>1) It must be the first line in the script.</b>
<br><b>2) The hash (#) must be the first character on the line, and there</b>
<br><b>&nbsp;&nbsp; cannot be anything between it and the bang (!).</b>
<br><b>3) You must use the absolute path, not just the executable name.</b>
<p>So, let's try writing our first Perl script:
<p>
<br><tt>#!/usr/bin/perl</tt>
<br><tt># "goodbye" - a modern, high-angst replacement for "Hello World"</tt>
<p><tt>print "Goodbye, cruel world!\n";</tt>
<br><tt>unlink $0;</tt>
<br>
<p>Well... at least it says "goodbye" before going away; Ms. Manners would
be proud. What did we do here? Several things that are rather obvious:
first, the "hash-bang"; next, a line that tells us what the script does
- another thing that carries over from shell scripting, and is an excellent
idea (there's no such thing as too many comments in the code!) Next, we
print the message using the `print' function. Note the "\n" at the end
of the string: Perl does not automatically provide you with a line-feed,
so you get to decide whether you want one or not. Also, note the semi-colon
at the end of the statement: just like C, Perl demands those, and Woe Betide
The Hapless Programmer Who Forgets! Actually, Perl's error checking is
pretty good stuff, with relatively readable messages; it's just that semicolons,
being statement separators, often cause the error to be reported as being
on the next line down. If you're aware of that quirk, it's not a big deal.
Better yet, just remember to use the semicolons.
<p>The last line is what does the evil deed of erasing the file - "goodbye
cruel world" indeed. The "$0" is simply a reference to the name of the
script being executed, and "unlink" does the same thing as "rm". Note that
"$0" is a lot more useful than "goodbye" or even "./goodbye" - no matter
what the file has been named, "$0" returns that name.
<br>&nbsp;
<p><b>Oh, By The Way: Some Code Guidelines</b>
<p>Far be it from me to claim perfection in writing code: on past occasion,
I've done "write-only" code that would make anyone trying to read it turn
various colors. The thing is, I'm constantly trying to improve - and I'd
surely like to see that idea take hold.
<p>Perl treats "white space" - tabs and spaces - with the contempt it deserves,
i.e., it's ignored. Because of this, you can structure your Perl code to
convey the idea of what it is you're doing. Just to give one quick example:
<p><tt>@boats = ("Aloa", "Cheoy Lee", "Pearson", "Mason", "Swan", "Westsail",
"S2", "Petersen", "Hereshoff");&nbsp; # List of sailboats</tt>
<p>Here, we've filled an array called `@boats' with sailboats. OK, that
works - but it could be more understandable:
<p><tt>@array = ("Aloa",&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; # French OSTAR/IOR
boat</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "Cheoy Lee",&nbsp;&nbsp;
# Comfortable but expensive</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "Pearson",&nbsp;&nbsp;&nbsp;&nbsp;
# Strong but rather heavy</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "Mason",&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
# Well designed, but a bit of a pig</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "Swan",&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
# Classy boat - if you've got the money</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "Westsail",&nbsp;&nbsp;&nbsp;
# Wetsnails are OK, for double-enders</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "S2",&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
# Nice bay boats - not for offshore use</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "Petersen",&nbsp;&nbsp;&nbsp;
# Steel world cruiser, roomy but slow</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "Hereshoff");&nbsp;
# Fast and gorgeous; cramped and expensive</tt>
<p>These habits apply to more than just Perl. Most modern languages allow
additional whitespace in order to make the code human-readable. As I go
through this series, I'll do my best to demonstrate at least my own version
of good coding style; I'd like to encourage everyone to make it a consideration
in writing their own code.
<br>&nbsp;
<p><b>Variables</b>
<p>In Perl, the focus is "ease of use". It is a so-called "loosely-typed"
language, where the variable definitions are not rigidly forced into straightjackets;
in fact, there's no way to define a variable that will <b>only</b> hold
a positive 32-bit floating point number.
<p>The three types of variables in Perl are <u>scalars</u>, <u>arrays</u>,
and <u>hashes</u>. Despite the scary names, they're all rather simple:
just variables that contain different arrangements of data.
<p><b>scalars</b> - numbers, strings, or references
<br>A scalar variable is denoted by a `$' sign, i.e. <tt>$num, $joe, $pointer</tt>
<br>Examples:
<br><tt>"0.0421", "Joe's glove", memory location "0xA000"</tt>
<p><b>arrays</b> - sequentially-numbered lists of scalars
<br>An array variable is denoted by an `@' sign, i.e. <tt>@v, @list, @variable</tt>
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Example:
<br><tt>&nbsp;&nbsp; 0 - "Sunday"</tt>
<br><tt>&nbsp;&nbsp; 1 - "Monday"</tt>
<br><tt>&nbsp;&nbsp; 2 - "Tuesday"</tt>
<br><tt>&nbsp;&nbsp; 3 - "Wednesday"</tt>
<br><tt>&nbsp;&nbsp; ...</tt>
<p><b>hashes</b> - key-referenced lists of scalars
<br>Hashes are denoted by '%', i.e. <tt>%people, %x, %this_is_a_hash</tt>
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Example:
<br><tt>&nbsp;&nbsp; resident - "Sherlock Holmes"</tt>
<br><tt>&nbsp;&nbsp; addr&nbsp;&nbsp;&nbsp;&nbsp; - "221B Baker Street"</tt>
<br><tt>&nbsp;&nbsp; code&nbsp;&nbsp;&nbsp;&nbsp; - "NW1"</tt>
<br><tt>&nbsp;&nbsp; city&nbsp;&nbsp;&nbsp;&nbsp; - "London"</tt>
<br><tt>&nbsp;&nbsp; country&nbsp; - "GB"</tt>
<br><tt>&nbsp;&nbsp; job&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; - "sleuth"</tt>
<br><tt>&nbsp;&nbsp; ...</tt>
<p>Note that, while arrays are stored in numerical order, hashes are not
- retrieving the first element of a hash will often have nothing to do
with the first element you loaded into it. Hash elements are referred to
by their keys, not their position in the structure.
<p>Within these three data types, you can contain (or point to) anything
you want - and access it easily.
<p>Another important note: $a, @a, and %a are completely unrelated to each
other. They are in different <u>name spaces</u>. I am careful not to use
visually conflicting names like these in my programs, especially since
things like
<tt>$a[0]</tt> (a reference to the 1st element of the @a array)
exist - but this is something you should be aware of.
<br>&nbsp;
<p>Given that variables can contain different types of data - numeric and
string - we're going to need operators that work for both types. Perl provides
these, and you should remember which type goes with what:
<p><tt>&nbsp;&nbsp; Operator&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
Num&nbsp;&nbsp;&nbsp;&nbsp; Str</tt>
<br><tt>&nbsp;&nbsp; --------------------------------------</tt>
<br><tt>&nbsp;&nbsp; Equal&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
==&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; eq</tt>
<br><tt>&nbsp;&nbsp; Not equal&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
!=&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; ne</tt>
<br><tt>&nbsp;&nbsp; Less than&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
&lt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; lt</tt>
<br><tt>&nbsp;&nbsp; Greater than&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; gt</tt>
<br><tt>&nbsp;&nbsp; Less than or equal to&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
&lt;=&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; le</tt>
<br><tt>&nbsp;&nbsp; Greater than or equal to&nbsp;&nbsp; >=&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
ge</tt>
<p>Easy mnemonic - when comparing letters (strings), use letters.
<p>Since I like to give concrete examples, here's a way to give yourself
gray hair and a nervous breakdown:
<br>
<br><tt>#!/usr/bin/perl</tt>
<br><tt># A political evaluation script</tt>
<p><tt>$a = "Al";</tt>
<br><tt>$b = "George";</tt>
<p><tt>if ( $a > $b)&nbsp;&nbsp; { print "$a would make a better President.\n";
}</tt>
<br><tt>if ( $a &lt; $b)&nbsp;&nbsp; { print "$b would make a better President.\n";
}</tt>
<br><tt>if ( $a == $b)&nbsp; { print "$a or $b, there's no difference...\n";
}</tt>
<br>
<p>Hm. The output says that there's no difference. This may reflect political
reality, but what about our comparisons?... oh yeah. We should have used
string operators, huh?
<p>
<br><tt>#!/usr/bin/perl</tt>
<br><tt># A political evaluation script</tt>
<p><tt>$a = "Al";</tt>
<br><tt>$b = "George";</tt>
<p><tt>if ( $a gt $b)&nbsp;&nbsp; { print "$a would make a better President.\n";
}</tt>
<br><tt>if ( $a lt $b)&nbsp;&nbsp; { print "$b would make a better President.\n";
}</tt>
<br><tt>if ( $a eq $b)&nbsp;&nbsp; { print "$a or $b, there's no difference...\n";
}</tt>
<br>
<p><u>Now</u> the comparison operators work properly (and the real-world
logic is backwards... but I digress.)
<p>By the way - why is it that Perl decided that "Al" was the same as "George"
in the first example? Since when do programs have political opinions?
<p>The reason is actually an important one - it has to do with the way
that Perl separates "true" from "false". Given that all of our tests -
"if", "while", "until", etc. depend on that distinction, we need to understand
it.
<p><b>"0" is false, whether it is a number or a string.</b>
<br><b>All undefined variables (those that have not had a value assigned
to them) are false.</b>
<br><b>An empty string - "" or '' - is false.</b>
<br><b>Everything else is true.</b>
<p>All right, here's some tricky stuff - look at these values and decide
whether they're true or false:
<p><tt>"00"&nbsp;&nbsp;&nbsp; "-1"&nbsp;&nbsp;&nbsp; " "&nbsp;&nbsp;&nbsp;
"5 - 5"</tt>
<p>See note <a href="#1">[1]</a> at the end of this article for the answers.
<br>&nbsp;
<p>Another issue that is important is variable interpolation, which is
a way of determining whether something in quotes gets interpreted or not.
Here's an example:
<p><tt>$name =&nbsp; 'Bessie';</tt>
<br><tt>print&nbsp;&nbsp;&nbsp; 'Our cow is named $name.';</tt>
<p>Oops. The output reads
<p><tt>Our cow is named $name.</tt>
<p>I don't think any self-respecting cow would come if called something
like that (I won't even mention the difficulty of pronouncing it.) So,
how do we get Bessie to come to us?
<p><tt># Note the double quotes where the singles used to be!</tt>
<br><tt>$name =&nbsp; 'Bessie';</tt>
<br><tt>print&nbsp;&nbsp;&nbsp; "Our cow is named $name.";</tt>
<p>Successful animal husbandry (and those of you thinking dirty thoughts,
<b>stop
it</b>) via Perl. I <u>told</u> you you could do anything.
<p>What if we wanted to print the variable name? Perl makes that easy,
too.
<p><tt>$joe =&nbsp;&nbsp; "Joe";</tt>
<br><tt>print&nbsp;&nbsp;&nbsp; "The variable \$joe contains the value
$joe.";</tt>
<p>We can print any <u>metacharacter</u>, that is, characters that have
a special meaning in Perl, by <u>escaping</u> them - that is, preceding
them with a backslash. Take a look at this:
<p><tt>$joe =&nbsp;&nbsp; "Joe";</tt>
<br><tt>print&nbsp;&nbsp;&nbsp; "The variable \"\$joe\" contains the value
\"$joe.\"";</tt>
<p>Uh... TMTOWDI:
<p><tt>print&nbsp;&nbsp;&nbsp; 'The variable "$joe" contains the value
"', $joe, '".';</tt>
<p>Take your pick; just be sure you understand the difference. Note that
separate values in the "print" statement take a comma as a separator -
without one, it has a completely different meaning, which we'll discuss
in a future article.
<p>Before we wrap this up, one important consideration: when creating your
script file, always use the "-w" parameter as part of your hash-bang -
<p><tt>#! /usr/bin/perl -w</tt>
<p>This will generate warnings and tell you where the problems are in your
script. Be sure to use it if you're a Perl beginner... and be <u>doubly</u>
sure to use it if you're a Perl expert. The errors don't go away as you
progress; they just grow smarter. :)
<br>&nbsp;
<p><b>Wrap-up</b>
<p>This time around, we took a bit of a journey, skipping lightly over
the rocks and shoals of a simple intro. Next month, we'll get a little
deeper into it; perhaps explore arrays and hashes, and maybe dive head-first
into the incredibly powerful "regular expressions", or regexes of Perl.
My suggestion, meanwhile, is to try a few of the things we've talked about,
maybe do a little experimentation on your own - I've found that the best
way to learn a language is to hack until I hit the limits of my knowledge,
then bring my frustrations to someone who knows more than I do. You can't
get any good answers if you don't even know the questions.
<p>Happy Perl hacking!
<br>&nbsp;
<p>Ben Okopnik
<br><tt><font size=-1>perl -we '$@="\145\143\150\157\040\042\112\165\163\164\040\141\156".</font></tt>
<br><tt><font size=-1>"\157\164\150\145\162\040\120\145\162\154\040\110\141\143\153\145\162".</font></tt>
<br><tt><font size=-1>"\042\040\076\040\057\144\145\166\057\164\164\171";`$@`'</font></tt>
<br>
<br><a NAME="1"></a><b>Note [1]</b>: All true. None of them fit the "false"
categories: "00" is <u>not</u> the same as "0"; neither is "-1". A space,
" ", is not the same as an empty string (""), and "5 - 5", unless <u>evaluated</u>,
is not "0".
<p>References: "Perl: The Complete Reference", Martin C. Brown
<p>Relevant Perl man pages (available on any pro-Perl-y configured system):
<p><tt><font size=-1>perl&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; - overview&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
perlfaq&nbsp;&nbsp; - frequently asked questions</font></tt>
<br><tt><font size=-1>perltoc&nbsp;&nbsp; - doc TOC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
perldata&nbsp; - data structures</font></tt>
<br><tt><font size=-1>perlsyn&nbsp;&nbsp; - syntax&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
perlop&nbsp;&nbsp;&nbsp; - operators and precedence</font></tt>
<br><tt><font size=-1>perlrun&nbsp;&nbsp; - execution&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
perlfunc&nbsp; - builtin functions</font></tt>
<br><tt><font size=-1>perltrap&nbsp; - traps for the unwary&nbsp;&nbsp;
perlstyle - style guide</font></tt>
<p><tt><font size=-1>"perldoc" and "perldoc -f"</font></tt>
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2000, Ben Okopnik.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 61 of <i>Linux Gazette</i>, January 2001</H5>
<!-- *** END copyright *** -->
<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<H1><font color="maroon">Booting Linux from the NT Boot Menu</font></H1>
<H4>By <a href="mailto:p_padala@yahoo.com">Pradeep Padala</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<p>
Why an article on Linux in an NT boot menu? We have HOWTOs, don't we?
The HOWTOs give step by step instructions, but unfortunately
they don't provide everything we want. They are geared towards people who are
new to Linux and are very good at explaining things to
newbies. But when it comes to doing something out of the ordinary,
we're stuck. This article is a meant to fill that void.
</p>
<p>
To start with one, day I got the crazy idea that it would be nice to
have a single boot loader to boot everything from one manager instead of
having both a LILO and an NT boot manager. So which manager should I
choose? I chose NT boot manager because when we install LILO and
boot NT from it, NT still presents its own boot menu and it's annoying
enough
to need to be asked two times to boot the right operating system . So I
thought of removing LILO and using NT loader to present a nice menu for
booting all the operating systems I have. Okay then, How do we do it? I
searched through the HOWTOs. The mini HOWTO <a href="http://www.linuxdoc.org/HOWTO/
mini/Linux+NT-Loader.html">HOWTO NT OS Loader + Linux mini-HOWTO</a>
gives a good overview of the
process. But unfortunately my brain couldn't grasp the concept. As a
result, when I first followed the steps I got an unusable system. After
3 days of hard work and rebooting and fiddling with an unusable system
3 times, concepts began to become clear.</p>
<P> Here we Go.
<h3>NT Boot Loader</h3>
<p>
The NT boot loader loads the operating system image by reading the
initialization file boot.ini. Have a look at it now. It contains something
like:
</p>
<pre>
[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINNT
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Windows NT Workstation Version 4.00"
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Windows NT Workstation Version 4.00
[VGA mode]" /basevideo /sos
</pre>
<p>
this says to boot the operating system from the partition as
mentioned. That is it takes the first 512 bytes of information which
is required for booting the corresponding OS. So how do we boot Linux
using this concept. Simple! we can have the first 512 bytes of Linux
boot partition (the boot sector for Linux) in a file and give it to
NT boot manager. We can modify the boot.ini file as follows:</p>
<pre>
[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINNT
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Windows NT Workstation Version 4.00"
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Windows NT Workstation Version
4.00 [VGA mode]" /basevideo /sos
<b>C:\boot.lnx="Redhat Linux 6.2"</b>
</pre>
<p> Where boot.lnx is the file which contains the required 512 bytes.
But
we have to get the 512 bytes. How do we do that? The HOWTO gives a
good example of how to do it. Here we need the first 512 bytes of
Linux boot partition which says to NT just to boot Linux. So we make
a dummy lilo.conf file and pass it to LILO and tell it to install the
boot sector for linux at the top of Linux partition. Then we peel the
first 512 bytes from this and put it into a file and give it to NT.
Then we install LILO in MBR and take care of loading WINNT as the
default OS. We create the lilo.conf to write NT as default and
install it.
</p>
<h3>Let's do it.</h3>
<p>
First let me explain my example environment. I loaded Red Hat out
of the box with the default options during installation. It installs
LILO in MBR and updates it according to the options given during
installation regarding what other OSes (such as NT) you have. Here I
have
NT only. When I reboot after installation, LILO comes up with two
options to boot--Linux and DOS. When I enter DOS, it goes into NT boot
manager.
What are we trying to make? We want to make LILO start the NT boot
manger as default and in NT boot manager, we want to have an option
to
boot Linux.</p>
<p>
What are we trying to make? We want to make LILO to start NT boot manger as
default and in NT boot manager we want to have an option to boot Linux.
</p>
<p>
We start here. First boot into Linux. Make a dummy lilo.conf file like
this:
Copy lilo.conf to lilo.dummy and open lilo.dummy with vi. edit it to look
some thing like this:
</p>
<pre>
# lilo.dummy file
boot = /dev/hda3 # Linux resides in /dev/hda3 in my machine.
# replace it with the partition in which you installed linux
timeout=0 # Time out zero to avoid lilo waiting for us
vga = normal
read-only
default=linux
image = /boot/vmlinuz
label = linux
root = /dev/hda3
</pre>
<p>
Then execute LILO with this dummy file as the argument with the command. This
installs linux boot sector on /dev/hda3.
</p>
/sbin/lilo -C lilo.dummy<br>
Peel off the first 512 bytes with this command.<br>
dd if=/dev/hda3 of=boot.lnx bs=512 count=1 <br><br>
We copy the file boot.lnx to c drive. If c drive is mounted as /win/c we
copy with the command <br><br>
cp boot.lnx /win/c
<br>
or mount c drive and copy the file as
<br>
mount /dev/hda1 /win/c<br>
cp boot.lnx /win/c<br>
<br>
Then change the boot.ini file as indicated here.
<br>
<pre>
[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINNT
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Windows NT Workstation Version 4.00"
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Windows NT Workstation Version
4.00 [VGA mode]" /basevideo /sos
C:\boot.lnx="Redhat Linux 6.2"
</pre>
<h3>Installing LILO in MBR.</h3>
<p>
Just change the lilo.conf file to reflect winNT as the default OS with
no delay in booting into it and tell LILO to install it in MBR.
</p>
<pre>
boot = /dev/hda # Install it in MBR
timeout=0
vga = normal
read-only
default=win # We need NT as default
image = /boot/vmlinuz # We can remove this entry with out any
#problems as we will not be booting Linux from LILO
label = linux
root = /dev/hda3
other = /dev/hda1
label = win
</pre>
<p>
install LILO again. Before rebooting, make sure that you have a rescue disk
at hand. You can use the Red Hat installation disk as the rescue disk.
See the Pitfalls section to find out how to use to for rescue. or
You can make a boot disk with the command
</p>
mkbootdisk,
<br>
<br>
which you can use for rescue. See the <a href=http://www.linuxdoc.org/HOWTO/Bootdisk-HOWTO/index.html>Bootdisk-HOWTO</a> for more details on how to make boot disk.<br><br>
Then reboot and watch the magic.
<br>
<p>
Are you still unsatisfied? I know what is bothering you. You want LILO to
be eliminated completely. Do this. Get a DOS floppy that has fdisk and
boot the machine with the floppy. Then run "fdisk /mbr" to overwrite the
master boot record. I don't know what happens with this option. I am still
unsure about
this and if any one knows what this option does, please <a href="mailto: ppadala@hss.hns.com">
write to me</a>.
</p>
<ol><lh><h3>Pitfalls:</h3>
<li>
<p>
Remember every time you change your kernel or make any changes to
lilo.conf, you have to follow the process again and make a new copy of
boot.lnx and give it to NT.
</p>
<li>
<p>
If you have done some thing wrong and you can't boot Linux, then boot with
the rescue disk and install LILO again as follows:
</p>
(You can use red hat installaion CD as the rescue disk. At the installation menu type rescue and enter)<br><br>
<ul type=disc>
<li>boot with rescue disk<br>
<li>mount linux partition<br>
mount /dev/hda3 /mnt<br>
<li>change root<br>
chroot /mnt<br>
<li>change lilo.conf to some thing sane like
<pre>
boot = /dev/hda
timeout=500
prompt
vga = normal
read-only
default=linux
image = /boot/vmlinuz
label = linux
root = /dev/hda3
other = /dev/hda1
label = win
</pre>
<li>install lilo<br>
/sbin/lilo<br>
<li>do a sync and unmount /dev/hda3<br>
sync<br>
umount /mnt<br>
<li>Reboot<br>
/sbin/reboot<br>
</ul>
</ol>
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2000, Pradeep Padala.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 61 of <i>Linux Gazette</i>, January 2001</H5>
<!-- *** END copyright *** -->
<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <HR> <P>
<!--===================================================================-->
<!-- END header -->
<img SRC="misc/steffler/penguinInBalloon.gif" height=230 width=200 align=right>
<center>
<h1>
<img SRC="misc/steffler/makingSmalltalk.png" ></h1></center>
<center>
<h3>Bags o' Fun</h3>
<H4>By <a href="mailto:jagwar@magma.ca">Jason Steffler</a></H4></center>
<H2><a NAME="abstract"></a>Abstract</h2>
&nbsp;&nbsp;&nbsp; For those who haven't read the previous articles, be
sure to read <font size=+1><a href="#statementOfPurpose">the statement
of purpose</a></font> first.&nbsp; This month, we're going to discuss inheritence,
polymorphism, and abstract classes as well as introducing some collection
objects.&nbsp; For those looking to read the whole series locally or information
about upcoming articles, you can
<font size=+1><a href="http://www.magma.ca/~jagwar/makingSmalltalkForwardingPage.html">check
the MST page</a></font>.&nbsp; For those looking for further information
on learning Squeak, here are <a href="http://minnow.cc.gatech.edu/squeak/377">some
good resources</a>.
<h2>
<a NAME="quoteOfTheDay"></a>Quote of the day</h2>
"Why Smalltalk? Smalltalk uses a simplified version of English. Nouns and
verbs. Object are the nouns. Verbs are messages sent from one object to
the next. Easy as 1, 2, 3. It is no longer necessary to write cryptic programs.&nbsp;
This means that almost anyone can learn to write Smalltalk programs."
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; - Peter William Lount
<h2>
<a NAME="inheritence"></a>Inheritence</h2>
&nbsp;&nbsp;&nbsp; Last month, we were using <b>aPerson</b> object for
illustrative purposes.&nbsp; This month we'll only build on this example
briefly, as it quickly gets too contrived for my liking.&nbsp; Also, this
is a good opportunity to introduce the collection objects of Smalltalk.&nbsp;
We'll return to <b>aPerson</b> next month though, as the emphasis will
be on the building aspect, and not on the object itself.
<br>&nbsp;&nbsp;&nbsp; The notion of inheritence in OO is very similar
to the normal use of this term.&nbsp; Just like a person can inherit certain
characteristics from their parents, so too can objects inherit certain
characteristics from their parents.&nbsp; Objects inherit the methods and
instance variables of their parents, among other things.
<br>&nbsp;&nbsp;&nbsp; To get this discussion going, lets introduce the
object <b>anOrderedCollection, </b>whose class is <b>OrderedCollection</b>.&nbsp;
This is a very common object to use in Smalltalk.&nbsp; An <b>OrderedCollection</b>
is just what it sounds like:&nbsp; it's a collection of objects where order
is important.&nbsp; To better position the topics at hand, it'd useful
to have an idea of how you can use this type of collection:
<p><i>[ex1]</i>
<br>&nbsp;&nbsp;&nbsp; "Inspect this code.&nbsp; Here we're creating a
new
<b>OrderedCollection</b>, and asking it to add 1, then add 2, then
add 3, then finally return yourself"
<br><b>&nbsp;&nbsp;&nbsp; (OrderedCollection new)&nbsp; add: 1; add: 2;
add: 3; yourself.</b>
<p><i>[ex2]</i>
<br>&nbsp;&nbsp;&nbsp; "This is normally not written on one line, but is
written like this:"
<br>&nbsp;&nbsp;&nbsp; <b>(OrderedCollection new)</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; add: 1;</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; add: 2;</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; add: 3;</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; yourself.</b>
<p>&nbsp;&nbsp;&nbsp; Here, we're asking the class (remember, this is a
blueprint for creating objects) <b>OrderedCollection</b> to create a new
collection.&nbsp; Then we're asking the new collection to add 1 to itself.&nbsp;
Then we're asking the same new collection to add 2 to itself, then 3, and
then finally we're asking the collection to return itself.&nbsp; You normally
don't have to send that last message to an object, as the default return
is the object itself (we call this the <a href="#articleGlossary">receiver</a>
of the the messages), but the message <b>add:</b> returns the parameter
you're passing, so in this case, if we want to see the <b>OrderedCollection</b>
that we're creating, we need to ask it to return itself as the last message
send.&nbsp; This may be a little confusing; I showed the above snippet
as it explicitly creates a new object.&nbsp; You could get the same results
by inspecting the below two snippets, that don't explictly create a new
object - this is done implicitly from the message sent:
<p><i>[ex3]</i>
<br>&nbsp;&nbsp;&nbsp; "Here, we're asking the <b>OrderedCollection</b>
class to give us a new <b>OrderedCollection</b> object with the values
1, 2, and 3 in it."
<br><b>&nbsp;&nbsp; OrderedCollection with: 1 with: 2 with: 3</b>
<p><i>[ex4]</i>
<br>&nbsp;&nbsp;&nbsp; "Here, we're asking the <b>OrderedCollection</b>
class to give us a new <b>OrderedCollection</b> object with all of the
values 1, 2 and 3<sup><a href="#footnotes">1</a></sup>"
<br>&nbsp;&nbsp;&nbsp; <b>OrderedCollection withAll: #(1 2 3)</b>
<p><i>[ex5]</i>
<br>&nbsp;&nbsp;&nbsp; Now, if you <b>print it</b> to the above code, you'll
see an ASCII representation of the object:&nbsp; <b>OrderedCollection (1
2 3 )</b>.&nbsp; When you inspect the above code, and click on <b>self</b>
you will see:
<br><img SRC="misc/steffler/orderedCollection1.png" height=203 width=273>
<p><i>[ex6]</i>
<br>&nbsp;&nbsp;&nbsp; There are several ways that we could make an ordered
collection with a fourth <b>Integer</b> in it, here's a neat way.&nbsp;
Say that you have this <b>OrderedCollection</b> with only the first 3 integers
in it, and realize 'wups, I actually wanted 4 integers in it.'&nbsp; You
don't have to go back to the code you typed in above and redo it, you can
just ask the object you're inspecting to add a fourth integer to itself:
<br><img SRC="misc/steffler/orderedCollection2.png" height=201 width=272>
<p><i>[ex7]</i>
<br>&nbsp;&nbsp;&nbsp; Highlight the code entered in the bottom pane, and
<b>do
it.&nbsp; </b>Here, you're asking the object itself (<b>self</b>) to add
4 to itself.&nbsp; If you have <b>self</b> highlighted, you'll notice that
it is updated (if you don't have <b>self</b> highlighted, then click on
it to see the updates.&nbsp; You'll see:
<br><img SRC="misc/steffler/orderedCollection3.png" height=199 width=249>
<p>&nbsp;&nbsp;&nbsp; This is an illustration of being able to view and
manipulate objects in real time, which is <b>Immensely Powerful</b>.&nbsp;
If you're coding along and something isn't quite working right, you can
stop execution, grab the troublesome object and see exactly what is going
on.&nbsp; If you want to simulate certain conditions, <u>you can just change
the object directly</u>.&nbsp; For example, say you realized that you shouldn't
have the integer 4, but rather the string 'four', you can click on the
fourth element, delete 4, and tye in <b>'four'</b>, then <b>middle click>accept.
</b>The
fourth element in this collection is now the string <b>'four'.
</b>Try
clicking on the 3rd element, then back to the fourth element to confirm
this, you'll see:
<br><img SRC="misc/steffler/orderedCollection4.png" height=199 width=249>
<p>&nbsp;&nbsp;&nbsp; ...and remember, we did all this without the hassle
of compiling, linking, and running the compiled program!&nbsp; Ok, now
that we have an idea about how to create a collection, we're going to do
something with this collection, lets add up the integers in the collection.&nbsp;
To do this, you can <b>do it</b> the following snippet:
<p><i>[ex8]</i>
<br><b>&nbsp;&nbsp;&nbsp; | anOrderedCollection aSum |</b>
<br><b>&nbsp;&nbsp;&nbsp; aSum := 0.</b>
<br><b>&nbsp;&nbsp;&nbsp; anOrderedCollection := OrderedCollection withAll:
#(1 2 3).</b>
<br><b>&nbsp;&nbsp;&nbsp; anOrderedCollection do: [:anElement | aSum :=
aSum + anElement].</b>
<br><b>&nbsp;&nbsp;&nbsp; aSum inspect.</b>
<p>&nbsp;&nbsp;&nbsp; Here, the lines of code mean:
<br>&nbsp;&nbsp;&nbsp; 1) declare temporary variables
<br>&nbsp;&nbsp;&nbsp; 2) initialize the sum
<br>&nbsp;&nbsp;&nbsp; 3) create a new ordered collection, assign it to
one of the temporary variables
<br>&nbsp;&nbsp;&nbsp; 4) ask the ordered collection to do something for
each element.&nbsp; For each element, we're asking the sum to add the element
to itself.
<br>&nbsp;&nbsp;&nbsp; 5) here, we're asking the sum to open an inspector
on itself (yeah, you can do this programatically - cool eh?)
<p>&nbsp;&nbsp;&nbsp; For the folks with programming experience, you'll
note that we didn't have to worry about bounds checking, or the size of
the collection, or declaring temporary variables to index the collection
- this is all handled by the collection.&nbsp; Very nice and it helps to
reduce errors.&nbsp; We very naturally just asked the ordered collection
to <b>do</b> something with each element.
<br>&nbsp;&nbsp;&nbsp; Back to inheritence now, as the name suggests, <b>OrderedCollection</b>
is a type of <b>Collection</b>, and inherits methods and instance variables
from <b>Collection.&nbsp; </b>To be more precise, it inherits from a class
called <b>SequenceableCollection</b>, which in turn inherits from <b>Collection.</b>&nbsp;
Now, I could use UML, or any number of other industry software modeling
diagrams here, but I want to save time so I'm going to use a textual shorthand
for outlining class relationships - I'll denote inheritence by tabbing,
so indicating the above inheritence looks like this:
<br><b>&nbsp;&nbsp;&nbsp; Collection</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; SequenceableCollection</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
OrderedCollection</b>
<p>&nbsp;&nbsp;&nbsp; You can think of this as <b>OrderedCollection </b>is
a type of <b>SequenceableCollection</b>, which is a type of <b>Collection.</b>&nbsp;
For example, a creation method we used - <b>withAll:</b> is inherited from
<b>Collection</b>,
I'll show this <a href="#articleGlossary">class method</a> by:
<br><b>&nbsp;&nbsp;&nbsp; Collection</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; >>withAll:</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; SequenceableCollection</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
OrderedCollection</b>
<p>&nbsp;&nbsp;&nbsp; Both <b>Collection</b>, and <b>SequenceableCollection</b>,
are what we call <a href="#articleGlossary">abstract classes</a> - classes
that would never instantiate an object themselves, but serve as good logical
building points.&nbsp; Here, it doesn't matter if we have an <b>OrderedCollection,
or
</b>a <b>SortedCollection</b>, or a <b>Bag </b>(an unordered collection),
or whatever - we'd want all of them to know how to respond to <b>withAll:</b>.
<u>Here's
the sweet thing:</u>&nbsp; we implement the method that all these classes
should respond to <i>in one spot<b>,</b> and reuse it. </i>So, if you need
to change withAll: for these classes, <i>then there's only one spot to
go to</i>.
<br>&nbsp;&nbsp;&nbsp; If you need to have an exception to the rule, say
you have have a <b>Heap</b><sup><a href="#footnotes">2</a></sup> class
that needs to implement the <b>withAll: </b>method differently, then you
can do what is called <a href="#articleGlossary">overriding</a> the method
in <b>Heap</b>.&nbsp; Adding <b>Heap</b> to our outline, and indicating
abstract classes in italics gives us:
<br><b><i>&nbsp;&nbsp;&nbsp; Collection</i></b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; >>withAll:</b>
<br><b><i>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; SequenceableCollection</i></b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
OrderedCollection</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
Heap</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
>>withAll:</b>
<p>&nbsp;&nbsp;&nbsp; Note:&nbsp; when we send the <b>withAll:</b> message
to <b>Heap</b> or to <b>OrderedCollection, </b><i>these two classes have
different implementation of the same message</i> - this is known as <a href="#articleGlossary">polymorphism</a><i>.
</i>This
is another one of those esoteric terms that really means something pretty
simple.
<br>&nbsp;&nbsp;&nbsp; The corollary of polymorphism is a very powerful
one though, it allows you to <i>get out of a decision making</i> frame
of mind, and <i>get into a commanding frame</i> of mind.<i> </i>This allows
us to get away from a common procedural programming trait - having lot
of code that is checking stuff and conditionally doing stuff (if it's an
<b>OrderedCollection</b>,
do this, if it's a <b>Heap</b>, do this, if it's a <b>Bag</b>, do this,
etc), and lets us just do stuff.&nbsp; It doesn't matter what type of collection
it is, when we ask it to do <b>withAll:</b>, it will do the right thing!
<br>&nbsp;&nbsp;&nbsp; Finally, if we also add the above mentioned <b>SortedCollection
</b>and<b>
Bag </b>(&lt;groan> here's where this month's title pun comes from ;-),
we get:
<br><b><i>&nbsp;&nbsp;&nbsp; Collection</i></b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; >>withAll:</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Bag</b>
<br><b><i>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; SequenceableCollection</i></b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
OrderedCollection</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
SortedCollection</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
Heap</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
>>withAll:</b>
<p><b>&nbsp;&nbsp;&nbsp; </b>It's easy to see how there are lots of opportunities
for reuse here, it's generally a good thing when you can code something
in one spot, and have many objects reuse that one implementation.&nbsp;
That way, when you have to make an udpate, you only update that one spot
and don't have to worry with tracking down many different spots and keeping
the update in synch.
<br>&nbsp;&nbsp;&nbsp; Now we're going to start getting to the question
of how we know what objects are where and how to use them.&nbsp; As with
other topics in this series, I'm introducing this one a bit at a time as
well.&nbsp; A common problem for Smalltalk beginners is that they're overwhelmed
with the rich class library as there are thousands of objects you can use.&nbsp;
To help reduce this problem, I've extended one of the Smalltalk browsers
and made a <b>ScopedBrowser</b>.&nbsp; This is a good example of the reflectiveness
we mentioned earlier - I was able to extend or alter the behavior of the
IDE to suit my needs.&nbsp; This <b>ScopedBrowser</b> will only show you
the classes we need to concentrate on for this article.&nbsp; My intent
is to add to the scope that is being browsed over time as more objects
are introduced.&nbsp; For this time, I've included all the above mentioned
collections objects as well as a couple more collections objects for those
interested (a total of 9 classes).&nbsp; To open this browser, you first
need to file in the <a href="misc/steffler/MakingSmalltalk-Article3.st">MakingSmalltalk-Article3.st</a>
code to your image (<a href="../issue60/steffler.html#puttingItAllTogether">see
article 2 on how to do this</a>).&nbsp;
Then open the browser by doing the snippet:
<p><i>[ex9]&nbsp;&nbsp;&nbsp; [Squeak-only-suspected]</i>
<br><b>&nbsp;&nbsp;&nbsp; ScopedBrowser openBrowserForArticle3</b>
<p>&nbsp;&nbsp;&nbsp; For the read-along folks, this is what you'll see
after navigating to the <b>withAll:</b> method:
<br><img SRC="misc/steffler/scopedBrowser1.png" height=283 width=582>
<br><font size=-1>&nbsp;&nbsp;&nbsp; <i>(Note: I set my browser colour
to purple - the default colour is green, I'll come back to customization
in a future article)</i></font>
<br>&nbsp;&nbsp;&nbsp; To find the <b>withAll:</b> method, click on the
<b>class</b>
button, then <b>Collections-Abstract>Collection>instanceCreation>withAll:</b>
<br>&nbsp;&nbsp;&nbsp; This browser has 5 panes and 3 buttons, from left
to right and top to bottom:
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; pane 1: shows categories
- these are collections of classes <i>(pun intended)</i>
<br><i>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </i>pane 2: shows classes
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; pane 3: shows categories
- these are collections of methods
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; pane 4: shows methods
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; pane 5: shows Smalltalk
code
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; button 1: toggles the browser
to show the instance methods of the object
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; button 2: toggles the browser
to show the class comments
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; button 3: toggles the browser
to show the class methods of the object
<br>&nbsp;&nbsp;&nbsp; Now, if we step back a little bit, and click on
<b>Collections-Sequenceable>OrderedCollection</b>,
you'll see:
<br><img SRC="misc/steffler/scopedBrowser2.png" height=284 width=581>
<br>&nbsp;&nbsp;&nbsp; Note that the code pane shows who <b>OrderedCollection</b>
inherits from, as well as their instance variables, if you then go back
to the abstract classes and click on <b>SequenceableCollection</b>, you'll
notice that it inherits from <b>Collection</b> just as we discussed.&nbsp;
Take some time poking around these classes and get comfortable with navigating
in this browser.&nbsp; Look for the classes and methods we discussed above.
<br>&nbsp;&nbsp;&nbsp; Finally, I'm going to introduce one more browser
- the hierarchy browser.&nbsp; This one is good when you're concentrating
on hierarchies and inheritence when you're coding.&nbsp; To open it, first
click on <b>OrderedCollection</b> again, then <b>middle-click>spawn hierarchy</b>.&nbsp;
You'll see:
<br><i>[ex10]</i>
<br><img SRC="misc/steffler/hierarchyBrowser1.png" height=318 width=537>
<br>&nbsp;&nbsp;&nbsp; Note, that this browser hasn't been scoped, and
shows the full hierarchy.&nbsp; Notice that Collection inherits from an
object called <b>Object</b> - no surprise here, most things about Smalltalk
are just what you would expect.&nbsp; Finally, the topmost object is <b>ProtoObject</b>,
which implements some really fundamental methods.&nbsp; The question naturally
arises:&nbsp; "What does <b>ProtoObject</b> inherit from?".&nbsp; The answer
is nothing, or <b>nil</b> to be more precise.
<h2>
<a NAME="lookingForward"></a>Looking forward</h2>
&nbsp;&nbsp;&nbsp; The next article will cover the making of aPerson; we'll
go over not only the basics of creating objects, but we'll also discuss
what the Smalltalk code that we're writing means.
<h2>
<a NAME="sweetSqueak"></a>A Sweet Squeak</h2>
This section won't explore/explain code or example, but merely present
a neat thing to try out.&nbsp; This time, we're going to look at downloading
projects.&nbsp; Remember in <a href="../issue59/steffler.html#firstLooks">article
1</a> when we created a new project?&nbsp; Well, you can not only save the project
to transfer across images, but you can drop it on the internet and download
it directly to your image too.&nbsp; Here's an example, do this:
<p><i>[ex11]&nbsp;&nbsp;&nbsp; [Squeak-only-suspected]</i>
<br><b>&nbsp;&nbsp;&nbsp; Project thumbnailFromUrl:&nbsp;&nbsp;&nbsp;&nbsp;
'http://www.squeak.org/Squeak2.0/2.7segments/SqueakEasy.extSeg'</b>
<p>&nbsp;&nbsp;&nbsp; For the read-along folks, you'll see a simple turtle
game project, and when you enter the project you can direct the turtle
by entering Smalltalk code:
<br><img SRC="misc/steffler/turtleGame1.png" height=479 width=639>
<h2>
<a NAME="questionsAndAnswers"></a>Questions and Answers</h2>
These are the answers for questions on previous articles that I could work
through in my limited time available.&nbsp; I picked out the ones I thought
most appropriate for the series.&nbsp; If you want a faster response, or
I didn't get to your question, try posting your question to the comp.lang.smalltalk
newsgroup, or the <a href="http://minnow.cc.gatech.edu/squeak/1">Swiki</a>.
<p><b>Q: How compatible with [VisualWorks, VisualAge, Smalltalk/X, Dolphin,
etc] Smalltalk will the code examples be?</b>
<br>A:&nbsp; Though I'm not writing these articles with code portability
in mind, and I'm not doing any portability testing, much of the basic code
should be compatible.&nbsp; By basic code, I mean things like how collections
are used, how classes are declared, instance variable use, etc.&nbsp; Traditionally
where the different flavours of Smalltalk differ most is in GUI code.&nbsp;
With Squeak specifically, some of the cool stuff we're going to look at
isn't portable to other flavours, for example:&nbsp; the halo stuff, morphic
stuff, and downloading projects.
<br>&nbsp;&nbsp;&nbsp; What I'll start doing though, is any code that I
a priori suspect is Squeak specific, I'll tag with<b> </b><i>[Squeak-only-suspected]</i><b>.&nbsp;
NOTE:&nbsp; </b>this will only indicate my <i>suspicion</i> - I don't plan
on spending time on testing it in different flavours, or searching for
ways to accomplish the same task in a different manner.
<br>&nbsp;&nbsp;&nbsp; This would be a great use of the Linux Gazette's
talkback sections - if other Smalltalkers note what does and doesn't work
in other flavours, they can post this info.&nbsp; Also starting with this
article, I'll start indexing the examples so they're easier to refer to
for this purpose (ie: ex1, ex2).&nbsp; I haven't done this yet, as I wanted
to keep the series informal, but I expect enumerating examples will make
it easier/clearer to post talkbacks.&nbsp; If you don't like the enumerating
- post a talkback.
<h2>
<a NAME="articleGlossary"></a>Article Glossary</h2>
This is a glossary of terms that I've used for the first time in this series,
or a term that I want to refine.&nbsp; <!-- If you don't see a term defined
here, try the ongoing glossary in the local location: <a href="../ongoingSeriesGlossary.html">[LL].</a -->
<br><b>abstract class</b>
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; A class that would never
instantiate an object itself, but serves as good logical building point
for other classes that do instantiate themselves (concrete classes).&nbsp;
Abstract classes are indicated <i>in italics</i> in class outlines.
<br><b>class method</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </b>(def1 - simple) A
method that a class implements (as opposed to an instance), usually to
create a new object.&nbsp; I denote a class method by: &gt;&gt;aClassMethod
<br><b>concrete class</b>
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; A class that would instantiate
an object itself.
<br><b>instance method</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </b>(def1 - simple) A
method that an instance of an object implements (as opposed to it's class).&nbsp;
I denote an instance method by: &gt;anInstancemethod
<br><b>polymorphism</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </b>When two different
objects interpret the same message differently by implementing two different
methods.
<br><b>receiver</b>
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The receiver of a message
send.&nbsp; The object that receives a message send.&nbsp; For example,
if we say <b>aPerson sing</b>, the receiver of the <b>sing</b> message
is <b>aPerson</b>
<br><b>[Squeak-only-suspected]</b>
<br><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </b>This tag is for any code
that I a priori suspect is Squeak specific<b>.&nbsp; NOTE:&nbsp; </b>this
will only indicate my suspicion - I don't plan on spending time on testing
it in different flavours, or searching for ways to accomplish the same
task in a different manner.
<h2>
<a NAME="footnotes"></a>Footnotes</h2>
[1] For those folks who have programming experience, the parameter that
we're passing here is an <b>Array</b>, you can just highlight the array
and inspect it too if you like.&nbsp; The reason I'm not using an <b>Array</b>
for illustrative purposes here, as because they are not as flexible or
user friendly as an <b>OrderedCollection</b>.&nbsp; Where arrays have a
fixed size, an ordered collection grows or shrinks as you need it to.
<br>[2] For those folks never lucky enough to be in a comp sci class that
studies heaps and stacks and other data structures&nbsp; adnauseam, a heap
is a type of binary tree in which the value of each node is greater than
the values of its leaves.
<p>
<h2>
<a NAME="statementOfPurpose"></a>Statement of purpose</h2>
&nbsp;&nbsp;&nbsp; When I wrote the first Making Smalltalk with the Penguin
<a href="../issue51/steffler.html">article
back in March of 2000</a>,
my target audience was experienced programmers who didn't have much exposure
to <a href="#articleGlossary">OO</a> programming or to Smalltalk.&nbsp;
The article's intent was to give an overview of my favourite programming
language on my favourite operating system.&nbsp; Since then, I've had a
fair amount of email asking introductory type questions about Smalltalk
and OO programming.&nbsp; So I thought I'd try my hand at a small series.
<br>&nbsp;&nbsp;&nbsp; The target audience for this series are people new
to OO or new to programming altogether.&nbsp; The intent is to not only
introduce OO programming, but to also spread the fun of Smalltalking.&nbsp;
Why do this format/effort when there's lots of good <a href="http://minnow.cc.gatech.edu/squeak/377">reference
material out there</a>?&nbsp; Two reasons really:&nbsp; 1) Tutorials are
great, but can be static and dated pretty quickly.&nbsp; 2) An ongoing
series tends to be more engaging and digestible.
<br>&nbsp;&nbsp;&nbsp; To help address the second reason above, my intent
is to keep the articles concise so they can be digested in under an hour.&nbsp;
Hopefully, as newbies follow along, they can refer back to the original
article and make more sense of it.&nbsp; I plan on having a touch of advanced
stuff once in a while to add flavour and as before, the articles are going
to be written for read-along or code-along people.
<!-- br>&nbsp;&nbsp;&nbsp; Something new I'm going to try is to make the ongoing
series viewable in a contiguous fashion and downloadable in one chunk for
people who want to browse the series locally.&nbsp; To do this, click on
TOC grapic to at the top of the article.&nbsp; The articles also have 2
sets of links:&nbsp; one set for www links, another set for local links,
indicated as: <a href="#articleGlossary">[LL]</a> for downloaded local
reading.-->
<h2>
<a NAME="whySmalltalk"></a>Why Smalltalk?</h2>
&nbsp;&nbsp;&nbsp; I believe Smalltalk is <b><u>the best</u></b> environment
to learn OO programming in because:
<ul>
<li>
Smalltalk has a very active and very helpful community; when you post a
question to the Smalltalk newsgroups you very often get an answer, unlike
many other newsgroups</li>
<li>
is very easy to learn... one of it's original design intentions was to
be a learning environment for children</li>
<li>
is a pure OO environment and encourages OO programming (as opposed to encouraging
procedural/Object mixed programming)</li>
<li>
cutting your teeth in Smalltalk makes you a better OO programmer in any
other language, because of the previous bullet</li>
<li>
is a portable environment:&nbsp; write once, run anywhere, so people can
learn on whatever OS they're running&nbsp; (as opposed to just the M$ variety)</li>
<li>
can look at and manipulate objects in real time; I haven't seen this ability
in any other environment</li>
<li>
Smalltalk is written in Smalltalk.&nbsp; You can view how the language
is put together to learn the language, and you can change anything that
you don't like about it.</li>
<li>
has garbage collection, no manual memory management, no explicit pointers</li>
<li>
is a literate language; by this I mean the syntax is very simple and is
geared towards programmer readability.</li>
<li>
there's lots of Cool Things that you can do in it that I haven't seen anywhere
else (will have some examples along the way)</li>
<li>
...and best of all: <b><u>it's fun</u></b>.</li>
</ul>
In particular, I'm going to use <a href="http://www.squeak.org/">Squeak</a>
as the playing vehicle.&nbsp; You'll notice this is a different flavour
of Smalltalk than I used in my first article.&nbsp; I've never used Squeak
before, so this'll be a learning experience for me too.&nbsp; The reasons
for this are:
<ul>
<li>
It's a completely opensource project</li>
<li>
It has some Really Cool features that I haven't seen in other flavours
of Smalltalk</li>
<li>
It has a comparitively small footprint and it's very easy to install</li>
<li>
It has a strong <a href="http://minnow.cc.gatech.edu/squeak/1">Swiki site</a>&nbsp;
(a <a href="#articleGlossary">Wiki</a> site hosted in Squeak, hence <b>S</b>queak
<b>Wiki</b>)</li>
</ul>
<h2>
<a NAME="personSampleCode"></a><b>Smalltalk Code</b></h2>
No listings this month
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2000, Jason Steffler.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 61 of <i>Linux Gazette</i>, January 2001</H5>
<!-- *** END copyright *** -->
<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<H1><font color="maroon">Setting Up a Linux Laptop With No CD-ROM Drive</font></H1>
<H4>By <a href="mailto:award@andorra.ad">Alan Ward</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<P>This
article comes mainly from my fiddling around with a laptop I bought
at a great price - US $800 some years ago - but lacking a CD-ROM drive. Just
what I needed to see how to get a Linux box going using the network
bootdisks that come with most distributions these days. I also have
some experience with the elderly 486 I recycle as terminals (no CD
drive either - and little else).</P>
<P>There
are different ways of exporting the distribution CD from a Linux
desktop: NFS, FTP and HTTP. I would like to discuss briefly each of
these, before going into some of the interesting problems I
encountered. I will try to keep this at a level accessible to all -
and the techniques <B>are</B> quite easy to use - though NFS can be
something of a bitch.</P>
<P>I
will use the RedHat distribution scheme here. Most of it also applies
directly to derived distributions, such as Mandrake or HispaLinux.
The ideas behind also apply to most other Linux distributions, though
the details of implementation may be different.</P>
<P><B>The
disks</B></P>
<P>Modern
distributions can usually be booted straight from the CD. But they
also come with several boot images that can be written to a floppy
(usually in the <I>/images</I> directory). There is a difference
between a desktop with a standard ISA or PCI ethernet card, and a
laptop with a PCMCIA card. In the latter, you will need to load the
pcmcia support module before the ethernet drivers.</P>
<P>For
example:</P>
<P>-
the RedHat 5.2 distribution comes with <I>boot.img</I> (both CD and
network), though you may also need <I>supp.img</I> for PCMCIA card
support. (And yes, I still use it to convert 486 and early Pentium
boxes into X terminals and routers - though not for servers!).</P>
<P>-
the RedHat 6.0 distribution comes with <I>boot.img</I> (CD only),
<I>bootnet.img</I> (network) and <I>pcmcia.img</I>.
</P>
<P ALIGN=LEFT STYLE="margin-bottom: 0in">-
Mandrake 7.0 comes with <SPAN STYLE="text-decoration: none"><I>cdrom.img</I></SPAN>,
<I>network.img</I> and <I>pcmcia.img</I>, as does Mandrake Corporate
Server.</P>
<P>In
each case, to boot from the network you will need:</P>
<DL>
<DD>
<TABLE WIDTH=460 BORDER=1 BORDERCOLOR="#000000" CELLPADDING=4 CELLSPACING=0>
<COL WIDTH=178>
<COL WIDTH=114>
<COL WIDTH=141>
<THEAD>
<TR VALIGN=TOP>
<TH WIDTH=178>
<P>distribution</P>
</TH>
<TH WIDTH=114>
<P>without PCMCIA</P>
</TH>
<TH WIDTH=141>
<P>with PCMCIA</P>
</TH>
</TR>
</THEAD>
<TBODY>
<TR VALIGN=TOP>
<TD WIDTH=178>
<P>
RedHat 5.2</P>
</TD>
<TD WIDTH=114>
<P>
boot.img</P>
</TD>
<TD WIDTH=141>
<P>
boot.img + supp.img</P>
</TD>
</TR>
<TR VALIGN=TOP>
<TD WIDTH=178>
<P>
RedHat 6.0</P>
</TD>
<TD WIDTH=114>
<P>
bootnet.img</P>
</TD>
<TD WIDTH=141>
<P>
bootnet.img + pcmcia.img</P>
</TD>
</TR>
<TR VALIGN=TOP>
<TD WIDTH=178>
<P>
Mandrake 7.0 and CS</P>
</TD>
<TD WIDTH=114>
<P>
network.img</P>
</TD>
<TD WIDTH=141>
<P>
pcmcia.img</P>
</TD>
</TR>
</TBODY>
</TABLE>
</DL>
<P>Naturally,
you can write these images to floppies using the <I>dd</I>
instruction. For example:</P>
<P><FONT FACE="courier, monospace">dd
if=/mnt/cdrom/images/network.img of=/dev/fd0</FONT></P>
<P><B>Getting
your network up</B></P>
<P>All
network boot disks have a mecanism to get your network up, though the
order in which the steps are taken may be slightly different. For
example, a Mandrake 6.1 boot goes:</P>
<OL>
<LI><P>select
network image protocol (nfs, ftp or http);</P>
<LI><P>select
a network card - this particular boot disk cannot detect your card
automagically - more on this later;</P>
<LI><P>enter
your IP and host configurations, which will in most cases be the
definitive configurations;</P>
<LI><P>tell
it about your server (IP address or name, directory holding the
distribution).</P>
</OL>
<P><B>Installing
through NFS</B></P>
<P>NFS
can be seen as the means Linux boxes have to share directories across
a local or wide area network. Once exported, you can mount these
directories just as you would a local disk unit.</P>
<P>Server-side,
I usually just mount the CD, and then export /mnt/cdrom. This
involves the following steps:</P>
<P>1.
Get the NFS server working (nfsd), for example using <FONT FACE="courier, monospace">setup.</FONT></P>
<P>2.
Mount the CD as usual:
</P>
<P><FONT FACE="courier, monospace">mount
/dev/cdrom /mnt/cdrom</FONT></P>
<P>3.
Include this directory in the server's list of exportable
directories. In <FONT FACE="courier, monospace">/etc/exports</FONT>,
I insert the line:</P>
<P><FONT FACE="courier, monospace">/mnt/cdrom
*(ro,no_root_squash)</FONT></P>
<P>This
means I want to export <I>/mnt/cdrom</I> to all users (<I>*</I>),
with read-only rights (<I>ro</I>). <I>no_root_squash</I> gives remote root
users root privileges over your NFS files; normally, remote root users have the
<EM>nobody</EM> user's permission on them--this is a security measure in case
the remote users are not trustworthy.
<P>5.
I then make the export effective with:</P>
<P><FONT FACE="courier, monospace">exportfs</FONT></P>
<P>This
should reply with a message such as:</P>
<P><FONT FACE="courier, monospace">/mnt/cdrom
localhost</FONT></P>
<P><FONT FACE="courier, monospace">/mnt/cdrom
*</FONT></P>
<P>You
can then test it out on any box on the network with (for example,
with 192.168.0.1 as the server's IP address):</P>
<P><FONT FACE="courier, monospace">mount
192.168.0.1:/mnt/cdrom /mnt</FONT></P>
<P>Client-side,
you will need to tell the installation program:</P>
<P>-
the NFS server name (or IP addess in most small networks with no DNS)</P>
<P>-
the RedHat directory, <FONT FACE="courier, monospace">/mnt/cdrom in
my example.</FONT></P>
<P>This
works, but may not be the easiest way to install Linux. I use it in
networks where the server exports <FONT FACE="courier, monospace">/home
anyway, and NFS is already set up.</FONT></P>
<P><B>Installing
through FTP</B></P>
<P>Server-side,
exporting a RedHat CD through ftp is a rather simple process. In my
setup, I already had the <I>wuftp</I> server going. The package on
installation creates the <I>/home/ftp</I> directory, from which
anonymous ftp queries are served. The most expeditive way the serve
the CD seemed to be:</P>
<P>1)
create a subdirectory, such as /home/ftp/cdrom</P>
<P><FONT FACE="courier, monospace">mkdir
/home/ftp/cdrom</FONT></P>
<P>2)
mount the CD directly on this directory, instead of the more usual
<I>/mnt/cdrom</I>:</P>
<P><FONT FACE="courier, monospace">mount
/dev/cdrom /home/ftp/cdrom</FONT></P>
<P>Just
to be sure, I then checked you can access this directory from an
anonymous ftp session.</P>
<P>Client-side,
I selected <I>FTP image</I>, then went through the normal steps to
set up networking. When asked, I gave it</P>
<P>-
the FTP site name (or IP addess in most small networks with no DNS)</P>
<P>-
the RedHat directory, just <FONT FACE="courier, monospace">cdrom in
my example.</FONT></P>
<P>It
seems you can also use non-anonymous ftp connections, but I haven't
tried it as it doesn't seem too interesting in our case.</P>
<P><B>Installing
through HTTP</B></P>
<P>The
process is very similar to the FTP.
</P>
<P>Server-side,
I used the standard <I>apache</I> installation, with DocumentRoot set
to <I>/home/httpd/html</I>. I then</P>
<P>1)
created a subdirectory, /home/httpd/html/cdrom</P>
<P><FONT FACE="courier, monospace">mkdir
/home/httpd/html/cdrom</FONT></P>
<P>2)
mounted the CD directly on this directory:</P>
<P><FONT FACE="courier, monospace">mount
/dev/cdrom /home/httpd/html/cdrom</FONT></P>
<P>I
also checked the CD was accessible before going on. You can do this
on the server itself by requesting <FONT FACE="courier, monospace">http://localhost/cdrom/</FONT>.
You should obtain a list of the files on the CD.</P>
<P>Client-side,
you need to give the installation program:</P>
<P>-
the Web site name (or IP address in most small networks)</P>
<P>-
the RedHat directory, just <FONT FACE="courier, monospace">cdrom</FONT> in
my example.</P>
<P><B>Wee
problems</B></P>
<P>With
my laptop, my major problem was a Trust PCMCIA ethernet card that is
advertised on the box as being &quot;full NE2000 compatible&quot; -
which is just not true. (Why do they supply their own drivers for
Windows 95?).</P>
<P>I
was stuck on that one with several distributions such as Mandrake
6.1: these ask you to give your card type. Naturally, the <I>ne</I>
module didn't work.</P>
<P>Then
I tried the RedHat 6.0 distribution. This autodetects the card type -
and works fine using module <I>pcnet_cs</I>. This rather weird card
type is not in the usual lists, but is incorporated into most
kernels. The trick is to get a boot disk that either autodetects or
lets you type in your module name instead of selecting from a list.
Note that the RedHat 6.0 network.img disk also works for Mandrake
6.1.</P>
<P>I
had a couple of problems with screen resolution under X. A 800x600
pixel laptop screen will work well with its own resolution - but not
with 640x480 as the pixels get distorted. I also had to fiddle with
the HorizSync value in <I>/etc/X11/XF86Config</I>: the standard VGA
30-40 kHz range worked better for me than the discrete values I got
telling the installation program I had a 800x600 LCD screen. Be
careful though - as ever with X.</P>
<P>Another
problem is when you forget some packages during initial installation.
You then need to get the packages accesible locally once more: either
mounting the CD from the server with NFS, or downloading the packages
via FTP or HTTP. You can then use <I>rpm</I>, <I>kpackage</I> or
whatever.</P>
<P><B>Further
steps</B></P>
<P>One
point I would like to look at is to compare the three system's
relative speeds. From what I saw while preparing this article, there
don't seem to be any major differences. So I guess it depends mostly
on which services are already installed on the server.
</P>
<P>In
most cases these will be FTP and HTTP, as their configuration is
automatic with most modern distributions. NFS seems a less probable
choice as most Linux boxes don't need it for everyday tasks.</P>
<P>Finally,
the last question I would like to discuss is &quot;why a laptop under
Linux&quot;?</P>
<P>Besides
the usual reasons for using Linux, I find it useful as a teacher:</P>
<UL>
<LI><P>to
use StarOffice (my favourite for projections);</P>
<LI><P>to
demonstrate operating system techniques <I>live </I>(also with the
projector);</P>
<LI><P>as
a server for the lab: students see both what happens on the server's
projected screen as well as on their own clients' screen and can
experiment;</P>
<LI><P>as
a portable X terminal;</P>
<LI><P>to
convince decision-makers and money-spenders Linux gets more bang
from hardware than other systems. You carry it around, plug it into
their local network, and let them play. My final line is: &quot;imagine
setting up Windows NT serving HTTP, FTP and mail on my P-133 CPU, 48
Mb RAM laptop ...&quot; Not to speak of Windows 2000 - but that
would be unkind :-)</P>
</UL>
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2000, Alan Ward.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 61 of <i>Linux Gazette</i>, January 2001</H5>
<!-- *** END copyright *** -->
<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <hr> <P>
<H1><font color="maroon">The Back Page</font></H1>
<ul>
<li><a HREF="#authors">About This Month's Authors</a>
<li><a HREF="#notlinux">Not Linux</a>
</ul>
<a name="authors"></a>
<P> <HR> <P>
<!--======================================================================-->
<center><H3><font color="maroon">About This Month's Authors</font></H3></center>
<P> <HR> <P>
<!--======================================================================-->
<!-- BEGIN bio -->
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Marius Andreiana</H4>
Marius is 20 years old, student in the second year at Politehnica
Bucharest, Romania
and working as a web developer. Besides Linux, he also loves music (from
rock to dance), dancing, having fun, spending time with friends.
He is interested also in science in general (and that quantum spooky
connection :)
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Shane Collinge</H4>
Part computer programmer, part cartoonist, part Mars Bar. At night, he runs
around in a pair of colorful tights fighting criminals. During the day... well,
he just runs around. He eats when he's hungry and sleeps when he's sleepy.
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Matteo Dell'Omodarme</H4>
I'm a student at the University of Pisa and a Linux user since 1994.
Now I'm working on the administrations of Linux boxes at the Astronomy section
of the Department of Physics, with special experience about security. My
primary email address is
<A HREF="mailto:matt@martine2.difi.unipi.it">matt@martine2.difi.unipi.it</A>.
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Eric Kasten</H4>
I'm a software developer by day and an artist, web developer,
big dog, gardener and wine maker by night. This all leaves very little
time for sleep, but always enough time for a nice glass of Michigan
Pinot Gris. I have a BS double major in Computer Science and
Mathematics and an MS in Computer Science. I've been using and
modifying Linux since the 0.9x days. I can be reached via email at
<A HREF="mailto:kasten@sunpuppy.com">kasten@sunpuppy.com</A> or through
my website at <A HREF="http://www.sunpuppy.com">http://www.sunpuppy.com</A>.
<p>
<h4><img align=bottom alt="" src="../gx/note.gif">Mark Nielsen</h4>
Mark works at ZING
(<A HREF="http://www.genericbooks.com">www.genericbooks.com</A>) and
<A HREF="http://GNUJobs.com">GNUJobs.com</A>. Previously,
Mark founded <A HREF="http://www.gnujobs.com">The Computer Underground</A>.
Mark works on non-profit and volunteer projects which promote free literature
and software. To make a living, he recruits people for GNU related jobs and
also provides solutions for web/database problems using Linux, FreeBSD, Apache,
Zope, Perl, Python, and PostgreSQL.
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Ben Okopnik</H4>
A cyberjack-of-all-trades, Ben wanders the world in his 38' sailboat, building
networks and hacking on hardware and software whenever he runs out of cruising
money. He's been playing and working with computers since the Elder Days
(anybody remember the Elf II?), and isn't about to stop any time soon.
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Pradeep Padala</H4>
I am a software engineer at Hughes Software Systems. I love hacking and adore
Linux. I graduated this year with a B.E (equivalent to B.S) in Computer Science
and Engineering. My intersets include solving puzzles and playing board games. I
can be reached through
<A HREF="mailto:p_padala@yahoo.com">p_padala@yahoo.com</A> or
<A HREF="http://pradeeppadala.homestead.com">http://pradeeppadala.homestead.com</A>.
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Jason Steffler</H4>
<a href = "http://www.magma.ca/~jagwar">Jason</a> is a Software Architect for
McHugh Software International.&nbsp;
His computer related interests include: OO programming &amp;
design, Smalltalking, the peopleware aspects of software, and noodl'n around
with Linux.
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Alan Ward</H4>
Alan teaches CS in Andorra at high-school and university levels. He's
back to Unix this year after an 8-year forced interlude since he
graduated -- it makes networking so much easier. His hobbies include
science photography (both digital and traditional), trekking, rock and
processor collecting.
<!-- END bio -->
<a name="notlinux"></a>
<P> <hr> <P>
<!--====================================================================-->
<center><H3><font color="maroon">Not Linux</font></H3></center>
<P> <HR> <P>
<!--======================================================================-->
<P>
<!-- *** BEGIN Not Linux *** -->
<P> Happy New Year, everybody!
<P> Michael Orr<br>
Editor, <A HREF="http://www.linuxgazette.com/"><i>Linux Gazette</i></A>, <A
HREF="mailto:gazette@ssc.com">gazette@ssc.com</a>
<BR CLEAR="all">
<!-- *** END Not Linux *** -->
<!-- *** BEGIN copyright *** -->
<P> <hr> <P>
<H5 ALIGN=center>
Copyright &copy; 2000, the Editors of <I>Linux Gazette</I>.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 61 of <i>Linux Gazette</i>, January 2001</H5>
<!-- *** END copyright *** -->
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