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<H2>July 2001, Issue 68 &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_mail68.html">The MailBag</A>
<LI> <a HREF="lg_bytes68.html">News Bytes</A>
<LI> <a HREF="lg_answer68.html">The Answer Gang</A>
<LI> <a HREF="lg_tips68.html">More 2-Cent Tips</A>
<LI> <a HREF="collinge.html">HelpDex</A> , <EM>by Shane Collinge</EM>
<LI> <a HREF="dellomodarme.html">Journalling Filesystems for Linux</A> , <EM>by Matteo Dell'Omodarme</EM>
<LI> <a HREF="ghosh.html">Compiling and Installing a Linux Kernel</A> , <EM>by Subhasish Ghosh</EM>
<LI> <a HREF="jenkins.html">A Linux Client for the Brother Internet Print Protocol</A> , <EM>by Graham Jenkins</EM>
<LI> <a HREF="mitchell.html">The Opening of the Field: PostgreSQL's Multi-Version Concurrency Control</A> , <EM>by Joseph Mitchell</EM>
<LI> <a HREF="nazario.html">Using RPM: The Basics (Part I)</A> , <EM>by Jose Nazario</EM>
<LI> <a HREF="nazario2.html">Chosing Good Passwords</A> , <EM>by Jose Nazario</EM>
<LI> <a HREF="qubism.html">Qubism</A> , <EM>by Jon "Sir Flakey" Harsem</EM>
<LI> <a HREF="swieskowski.html">Making an X Terminal from a PC</A> , <EM>by Patrick Swieskowski</EM>
<LI> <a HREF="lg_backpage68.html">The Back Page</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>
Ben Okopnik, Dan Wilder, Don Marti
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are files containing the entire issue: one in text format, one in HTML.
They are provided
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This page maintained by the Editor of <I>Linux Gazette</I>,
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<H1><A NAME="wanted"><IMG ALIGN=MIDDLE ALT="" SRC="../gx/mailbox.gif">
The Mailbag</A></H1> <BR>
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<center><H3><font color="maroon">HELP WANTED : Article Ideas</font></H3></center>
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<P> Send tech-support questions, answers and article ideas to The Answer Gang
&lt;<A HREF="mailto:linux-questions-only@ssc.com">linux-questions-only@ssc.com</A>&gt;. Other mail (including
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<!--====================================================================-->
<!-- BEGIN HELP WANTED : Article Ideas -->
<UL>
<!-- index_text begins -->
<li><A HREF="#wanted/1"
><strong>kernel tuner's helper</strong></a>
<li><A HREF="#wanted/2"
><strong>What Type of Hard disk ( SCSI/RAID)</strong></a>
<li><A HREF="#wanted/3"
><strong>WordPerfect 8 and RH 7.1</strong></a>
<li><A HREF="#wanted/4"
><strong>modem installation help</strong></a>
<li><A HREF="#wanted/5"
><strong>Microphone trouble</strong></a>
<li><A HREF="#wanted/6"
><strong>Viewing gzip'ed pages with Netscape</strong></a>
<li><A HREF="#wanted/7"
><strong>tighter mail security.... using SSL</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">kernel tuner's helper</FONT></H3>
Mon, 04 Jun 2001 14:56:15 +0200
<BR>Antonio Sindona (<a href="mailto:linux-questions-only@ssc.com?cc=Antonio.Sindona@italtel.it">Antonio.Sindona from italtel.it</a>)
<P>
There is a tool to monitor kernel parameters and to change the limits. I
explain better: I'd like to have a look in some occasions if there is some
kernel parameter which has reached its limit, and have the possibility to
change it. Moreover I'd like to see anyway ALL kernel parameters available
to set them to optimize it. With HP-UX there is a tool (SAM) which makes
this work. Any idea for a Linux box ?
Thanks in advance
</P>
<P>
Antonio Sindona
</P>
<!-- end 1 -->
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<P> <A NAME="wanted/2"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">What Type of Hard disk ( SCSI/RAID)</FONT></H3>
1 Jun 2001 20:29:11 -0000
<BR>Alpesh K and Sachin Vyas (<a href="mailto:linux-questions-only@ssc.com?cc=alpesh8@rediffmail.com,sachin-vyas@usa.net">both</a> alpesh8 from rediffmail.com AND sachin-vyas from usa.net)
<blockquote><font color="#000066">Both of these users asked pretty much the same question. They are SuSE users
but because the question is about the kernel overall, the result should be
useful to everyone. But this could also serve as the starting point for an
article about using RAID, or about working with the proc filesystem, or an
inspiration to write this "tool like an sg interface" they have conceived of.
If you decide to answer this directly, please mail both of them and cc
<A HREF="mailto:linux-questions-only@ssc.com"
>linux-questions-only@ssc.com</A>.
-- Heather</font></blockquote>
<P><strong>
Alpesh K
</strong></P>
<P>
Hi:
</P>
<P>
Is there a programming interface through which I can find out type of hard
disk ( SCSI/RAID)? I have Suse Linux 7.1 (x86) with two SCSI hard disks and
one SCSI is connected through AMI megaraid hardware RAID controller. RAID
driver is megarid and lsmod displays it.
</P>
<P>
I need to find out which is RAID/SCSI ? I looked at <TT>/proc/scsi/scsi</TT> but that
didn't tell which is SCSI/RAID.
</P>
<P>
But another <A HREF="http://www.suse.com/">SuSE</A> 7.1 system having Mylex h/w RAID controller and DAC driver
has <TT>/proc/rd/c*d*</TT> entry.
</P>
<P>
1. So why not there is an entry <TT>/proc/rd/c*d*</TT> on system which has AMI RAID controller?
</P>
<P>
2. Is there any ioctl through which I can find out which disk is SCSI/RAID, if device name ( <TT>/dev/sda</TT> , <TT>/dev/sdb</TT> etc.) is given.
</P>
<blockquote><font color="#000066">...in a later mail he added...
-- Heather</font></blockquote>
<P>
I looked at scsi generic interface(sg ) but as I understand It cann't be used for all the types of RAID Controllers.( Mylex DAC, Compaq smart array etc.)
A generic interface like sg which works for all the RAID controllers will be very helpful.
</P>
<P>
I looked at looked <TT>/proc/scsi/scsi</TT> and <TT>/proc/rd/c*</TT> but that may vary , so if I have to use <TT>/proc</TT> then I have to hardcode <TT>/proc</TT> pathname.
</P>
<P>
I will be very thankful if somebody tells me how do I do this.
</P>
<P>
Thanks in advance.
<br>Alpesh
</P>
<HR width="10%" align="center">
<P><strong>
sachin vyas
</strong></P>
<P>
Hi All:
</P>
<blockquote><font color="#000066">...Sachin asks similar questions as Alpesh, but adds:
-- Heather</font></blockquote>
<P>
Can I use <TT>/proc/partitions</TT> which will give all the disks then I can filter out
IDE by looking at <TT>/proc/ide</TT> , SCSI by <TT>/proc/scsi/scsi</TT> and remaining becomes
RAID ?
</P>
<P>
I will be very thankful if somebody tells me whether using <TT>/proc/partitions</TT>
is correct or not ? If not how this be done.
</P>
<P>
Thanks in advance,
<br>Sachin
</P>
<blockquote><font color="#000066">I believe that the remainder would also include old model CDROMs or tapes
that had private controllers.
-- Heather</font></blockquote>
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<P> <A NAME="wanted/3"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">WordPerfect 8 and RH 7.1</FONT></H3>
Fri, 25 May 2001 13:00:56 -0400
<BR>James P. Harlos (<a href="mailto:linux-questions-only@ssc.com?cc=harlos@localnet.com">harlos from localnet.com</a>)
<P>
For reasons which seemed good to me at the time I switched distos and
upgraded to RH 7.1. After some work everything seems to be ok except
for sound. However, I got a big surprise when I tried to load
WordPerfect 8 from CD. This is a purchased copy of WP 8 Personal
Edition that worked fine. The install script would not run! I went to
<A HREF="http://linux.corel.com/">Corel</A>'s site. They apparently don't help people who purchased their
product. In any event they seem to be more concerned with their new
product WP 2000. On one of their user group boards there was a tread
concerning this, suggesting the problem was in the initial install
script, install.wp. Well the long and short of it is I made the changes
suggested with no change in behavior. Do you have any answer?
</P>
<blockquote><font color="#000066">We don't have the script at hand, but someone who does might tell you
haw they forced it to install correctly. Which needn't be by using
what Corel provided.
-- Heather</font></blockquote>
<P>
I find it unfortunate that Corel takes the path of install scripts
rather than RPM or even tarballs. I used WP way back under DOS and
liked it. I liked it even more when the first verions of Word came
out. Sadly, WP rested on their laurels and their product withered.
When Corel brought out WP for Linux I thought this was good, tried out
the free download, liked it and bought it in version 8. After this I
will not buy another Linux product from Corel. Enough soapbox.
</P>
<P>
Jim Harlos
</P>
<blockquote><font color="#000066">I think it's worth mentioning that both the RPM format and DEB format,
plus possibly other packaging types, do have they ability to have install
and remove scripts. What you actually want is for them to work.
-- Heather</font></blockquote>
<!-- 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">modem installation help</FONT></H3>
Mon, 28 May 2001 10:22:05 -0700 (PDT)
<BR>bxb 3 (<a href="mailto:linux-questions-only@ssc.com?cc=bxb32001@yahoo.com">bxb32001 from yahoo.com</a>)
<P>
to the guys n' gals of tag:
</P>
<P><BLOCKQuote>
Hi! First of all I'm somewhat of a complete newbie and
that my brain is muck (overloaded, uncooperative and
maybe just almost totally inaccessible)from what I've
read and tried to understand... I just need a... well,
a quite simple explanation...
</BLOCKQuote></P>
<P>
I have an internal ESS ES28381 modem... I did a...
(what was it?).. a <TT>/cat</TT> <TT>/proc/pci</TT> whatever and got
this about the (uhmm PCI?):
</P>
<blockquote><pre>Bus 2, device 4, function 0:
Communication controller: ESS Technology ES28381).
IRQ 9.
I/o at 0xc400 [0xc40f]
</pre></blockquote>
<P>
Well thats about it and that under the other OS my
modem was at COM 4.
</P>
<P>
NOW WHAT DO I DO?
</P>
<P>
thanks anywayz.... and you don't really need to put
this in the mag if it doesn't sound that interesting
or if it seems totally dum... I agree I'm quite a bit.
I just need a little help so a reponse would be
greatly appreciated.
</P>
<blockquote><font color="#000066">wvdial or kisp might do it for you; but troubleshooting using modems
for the first time under Linux is worth an article in its own right.
-- Heather</font></blockquote>
<!-- end 4 -->
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<P> <A NAME="wanted/5"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">Microphone trouble</FONT></H3>
Tue, 5 Jun 2001 22:23:20 -0700
<BR>j_c_llings and Rafael Lepra (<a href="mailto:linux-questions-only@ssc.com?cc=j_c_lings@netzero.net,rlepra@adinet.com.uy">both</a> j_c_llings from netzero.net AND rlepra from adinet.com.uy)
<P><strong>
j_c_llings
</strong></P>
<P>
I have noticed that my microphone does not work in linux. The
impression I am getting is that this is common in the Linux community
since most folks don't use them and there are always bigger fish...(
er... penguins?) to fry. Would it be possible to convince you to cover
the general configuration and most common problems with microphones?
</P>
<hr width="10%" align="center">
<P><strong>
Rafael Lepra
</strong></P>
<P>
I have a motherboard GA 7ZX with a Creative PCI 128 sound chip. I have
installed RedHat 6.0 (I got the CD from a magazine). First of all I could
not initialize XWindows cause it did not recognize the Rage 128. I
downloaded and instal XFree86 4.02 and it worked.
</P>
<P>
But I have not been able to put the PCI 128 to work, the sistem just did not
find the chip. I have read the Sound How TO but it looked rather criptic to
a newby. Could you give me some advice. Please take into account I am quite
new in Linux.
</P>
<blockquote><font color="#000066">If someone would like to work with these two to improve these HOWTOs
(there are more than one related to sound, see
<A HREF="http://www.linuxdoc.org/HOWTO/HOWTO-INDEX/apps.html#MMAUDIO"
>http://www.linuxdoc.org/HOWTO/HOWTO-INDEX/apps.html#MMAUDIO</A>)
then you should also copy the author of the HOWTO you're going to be
looking at. But we'd love to see an article about just getting sound
going so you can play cute "tada" sounds and talk to your computer.
-- Heather</font></blockquote>
<!-- end 5 -->
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<P> <A NAME="wanted/6"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">Viewing gzip'ed pages with Netscape</FONT></H3>
Sat, 16 Jun 2001 00:32:54 +0900 (JST)
<BR>Aron Lentsch (<a href="mailto:linux-questions-only@ssc.com?cc=lentsch@nal.go.jp">lentsch from nal.go.jp</a>)
<P>
Dear Answer Gang!
</P>
<P>
In my previous version of Netscape (4.75) gzip'ed HTML
pages where displayed in just the same way as normal
(unzipped) html pages. However, after upgrading my
system including Netscape (now version 4.76), this
function is not available anymore.
</P>
<P>
What do I need to do, in order to make Netscape read
compressed html-pages again?
</P>
<P>
THANKS!
Aron
</P>
<blockquote><font color="#000066">A comparison review of the most recent web browsers and how easy or
hard they make common tasks such as this would be a <EM>very</EM> cool article.
-- Heather</font></blockquote>
<!-- end 6 -->
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<P> <A NAME="wanted/7"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">tighter mail security.... using SSL</FONT></H3>
Mon, 11 Jun 2001 02:01:37 +0800
<BR>Renato Tiongson III (<a href="mailto:linux-questions-only@ssc.com?cc=nats@mtech.com.ph">nats from mtech.com.ph</a>)
<P>
Hi,
</P>
<P>
I'm currently doodling around with rh 6.2 configured as a mail server with
sendmail as the mta. I'd like to know how to go about implementing SSL
for POP <TT>/</TT> IMAP &amp; SMTP? Also would like to know how to implement
authentication when relaying mail <TT>/</TT> SMTP.
</P>
<P>
Thanks in advance!
</P>
<P>
Nats
</P>
<!-- end 7 -->
<a name="mailbag"></a>
<P> <hr> <P>
<!-- =================================================================== -->
<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>Tired Newbie</strong></a>
<li><A HREF="#mailbag/2"
><strong>thanks</strong></a>
<li><A HREF="#mailbag/4"
><strong>Yet Another Helpful Email</strong></a>
<li><A HREF="#mailbag/5"
><strong>ssh-agent article</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">Tired Newbie</FONT></H3>
Wed, 20 Jun 2001 14:09:02 -0700
<BR>
Paul Bussiere &lt;<A HREF="mailto:webmaster@checksix.net"
>webmaster from checksix.net</A>&gt;
<P><STRONG><BLOCKQuote>
On the article in this month's Gazette
</BLOCKQuote></STRONG></P>
<P><STRONG>
<A HREF="../issue67/lg_mail67.html#mailbag/5"
>http://www.linuxgazette.com/issue67/lg_mail67.html#mailbag/5</A>
</STRONG></P>
<P><STRONG>
The link to The Answer Guys doesn't address anything from me, as alluded to
in the article. Had a few folks email me asking "Why didn't they answer
your questions?"
</STRONG></P>
<P><STRONG>
Just a heads up
</STRONG></P>
<P>
I'll let Heather respond re where that link was supposed to point to.
We did have a big debate about Unix PATH vs DOS PATH, but I'm unsure if
it got published. It would have been published under an unrelated topic,
I think about printing.
</P>
<blockquote><font color="#000066">No, he's quite correct, it got entirely
lost in the shuffle. A matter
which has been fixed, this time! I've made sure that cross-referenced
threads were the first to get handled. So check out TAG...
-- Heather</font></blockquote>
<P>
By the way, we did receive an offer for a WinDweeb column. Jeff Lim, a
self-titled WinDweeb, is preparing a regular column full of miscellaneous
Linux advice for those familiar with Windows. In particular, he wants to
provide straightforward "how-to" pieces for tasks he doesn't think are
covered adequately in the manpages and in the HOWTOs, or are so far buried
in them that you can't find the info you need. Look for it in next month's
issue. Thanks, Jeff! --Iron</P>
<!-- end 1 -->
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<P> <A NAME="mailbag/2"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">thanks</FONT></H3>
Mon, 04 Jun 2001 12:34:11
<BR>darrell rolstone (<a href="mailto:globalance@hotmail.com">globalance from hotmail.com</a>)
<P>
Dear Dan, ( and stern Heather too!)
</P>
<BLOCKQUOTE><FONT COLOR="red">
Actually, "stern Heather" Stern is not stern. She has a dry sense of humor,
looks like a punk girl, and wears a big red hat (no pun intended) with a wide
brim. --Iron
</FONT></BLOCKQUOTE>
<blockquote><font color="#000066">The complete thread he is thanking us for can be found in TAG this month.
Because he's offering his service to the community I also am mentioning it
here. I offer no opinions in any direction <EM>about</EM> his service - you'll
have to consider that on your own.
</font></blockquote>
<blockquote><font color="#000066">The long letter he is referring to is in the TAG list archives at
<A HREF="http://www.ssc.com/mailing-lists/tag/200105/0020.html"
>http://www.ssc.com/mailing-lists/tag/200105/0020.html</A>
</font></blockquote>
<blockquote><font color="#000066">He hopes to set up a site at <A HREF="http://www.team-synergy.org"
>http://www.team-synergy.org</A> but will need
technical help to do that.
-- Heather</font></blockquote>
<P>
Thanks SO MUCH for answering! Now I know that my letter did infact
arrive! I REALLY appreciate it and all that you and the other volunteers do.
I hope that my "interesting questions" generate some "food for thought"
among linux programmers! It looks like IBM and their new associates will be
addressing many of the drawbacks that I pointed out ....by paying their
programmers to code using the linux kernal (along with the NSA)! I hope that
"far-reaching" programs like the two I have initiated will garner monetary
support somehow!
</P>
<P>
Please know that I put myself "at your service" to the whole of the
linux community, as a "synergy design consultant" ( which pretty much covers
EVERYTHING) and would be glad to volunteer to contribute my prospective on
any projects/problems!
</P>
<P>
Remember: "<em>the significant problems we face today cannot be solved by
the same level of thinking that created them</em>" Albert Einstein.
</P>
<P>
May the Source be with you, Darrell Ernest Rolstone aka "Rollee"...w/o's
</P>
<!-- end 2 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="mailbag/4"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">Yet Another Helpful Email</FONT></H3>
Tue, 05 Jun 2001 08:04:47 -0700
<BR>Benjamin D. Smith (<a href="mailto:gazette@ssc.com">amp from benjamindsmith.com</a>)
<!-- sig -->
<P>
Read your post at June's Linux Gazette - And, it might be a good thing
to document the long and sometimes frustrating journey from the Windows
to *nix camps.
</P>
<P>
I once heard a teacher put it the best I've yet heard it.
</P>
<P>
Imagine a graph.
</P>
<P>
Windows gets you started and going quickly (line rises sharply) but you
rapidly run into the limitations of the system and Operating System, so
very quickly your productivity levels off.
</P>
<P>
*nix, on the other hand, has a steep learning curve, so steep that at
first your productivity actually DIPS (line drops below the "0" line) at
first, until you start to "get it". Then, as your knowledge accumulates
(took me about a year of using Linux primarily before I really "got
it") the productivity climbs, and just keeps climbing with how much you
learn.
</P>
<P>
I've not seen that there is a discernable cap - the more I look, the
more cool stuff I find I can do!
</P>
<P>
-Ben
</P>
<blockquote><font color="#000066">Ben has also submitted a 2c Tip for us, which is in this month's column.
-- Heather</font></blockquote>
<!-- end 4 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="mailbag/5"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">ssh-agent article</FONT></H3>
Tue, 05 Jun 2001 15:19:02 -0500
<BR>Dustin Puryear (<a href="mailto:gazette@ssc.com">dpuryear from usa.net</a>)
<P>
Dustin Puryear wrote to Jose Nazario, one of our authors:
</P>
<P><STRONG><BLOCKQuote>
Jose, I read your article on Linux Gazette about the SSH key agent.
</BLOCKQuote></STRONG></P>
<P>
(<A HREF="../issue67/nazario2.html"
>http://www.linuxgazette.com/issue67/nazario2.html</A>) in the June issue.
</P>
<P><STRONG>
Very
nice. However, I noticed you neglected to mention a way to load the
agent when the user logs in rather than doing so manually. Following is
a simple addition to a user's .bashrc (or edit for your particular
shell) that will do the job:
</STRONG></P>
<code><font color="#000033"><br># load local keys
<br>env | grep SSH_AGENT_PID &gt; /dev/null
<br>if [ $? -eq 0 ]; then
<br> ssh-add -l | grep $USER@$HOSTNAME &gt; /dev/null
<br> if [ $? -ne 0 ]; then
<br> ssh-add
<br> fi
<br>else
<br> ssh-agent /bin/bash
<br> exit
<br>fi
</font></code>
<P><STRONG>
Feel free to pass this on to your readers. Regardless, good work.
</STRONG></P>
<P><STRONG>
Regards, Dustin
</STRONG></P>
<!-- end 5 -->
<P> <hr> </p>
<!-- *** BEGIN copyright *** -->
<H5 align="center">This page edited and maintained by the Editors
of <I>Linux Gazette</I>
<a href="http://www.linuxgazette.com/copying.html"
>Copyright &copy;</a> 2001
<BR>Published in issue 68 of <I>Linux Gazette</I> July 2001</H5>
<H6 ALIGN="center">HTML script maintained by
<A HREF="mailto:star@starshine.org">Heather Stern</a> of
Starshine Technical Services,
<A HREF="http://www.starshine.org/">http://www.starshine.org/</A>
</H6>
<!-- *** END copyright *** -->
<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>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<font color="green">
July 2001 <I>Linux Journal</I>
</font>
</H3>
<IMG ALT=" " SRC="misc/lj-cover87.png" WIDTH=200 HEIGHT=268
ALIGN="left" HSPACE="20">
<P>
The July issue of <A HREF="http://www.linuxjournal.com/"><I>Linux
Journal</I></A> is on newsstands now.
This issue focuses on Program Development. Click
<A HREF="http://www.linuxjournal.com/lj-issues/issue87/index.html">here</A>
to view the table of contents, or
<A HREF="http://www.linuxjournal.com/subscribe/index.html">here</A>
to subscribe.
<P>
<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>.
<BR CLEAR="all">
<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">SuSE
</FONT>
</H3>
<a href="http://www.suse.de/en">SuSE Linux</a> 7.2 is Available from June 15th.
More details on the SuSE
<a href="http://www.suse.de/en/produkte/susesoft/linux/index.html">
products page</a>
<P> In further news, SuSE have
<a href="http://www.suse.de/en/news/hotnews/Oracle9i.html">
announced</a> that SuSE Linux has been validated
for <a href="http://www.oracle.com/">Oracle9i</a> Database..
<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> Listings courtesy <EM>Linux Journal</EM>. See <EM>LJ</EM>'s
<A HREF="http://noframes.linuxjournal.com/events/">Events</A> page for the
latest goings-on.
<!-- *** BEGIN events table [this line needed by Linux Gazette events.py *** -->
<table cellpadding=5 border=0 width=100%>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
<tr><td valign=top>
<b>Enterprise Linux Insititute Conference</b><BR>
<td valign=top>July 3-5, 2001<BR>London, UK<BR>
<A HREF="http://www.elxi.co.uk/"
target=_blank>http://www.elxi.co.uk</A><BR>
</td></tr>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
<tr><td valign=top>
<b>Linux Expo Exhibition</b><BR>
<td valign=top>July 4-5, 2001<BR>London, UK<BR>
<A HREF="http://www.linuxexpo.co.uk/"
target=_blank>http://www.linuxexpo.co.uk</A><BR>
</td></tr>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
<tr><td valign=top>
<b>Internet World Summer</b><BR><td valign=top>July 10-12, 2001<BR>
Chicago, IL<BR>
<A HREF="http://www.internetworld.com/" target=_blank>
http://www.internetworld.com</A><BR>
</td></tr>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
<tr><td valign=top>
<b>O'Reilly Open Source Convention</b><BR>
<td valign=top>July 23-27, 2001<BR>San Diego, CA<BR>
<A HREF="http://conferences.oreilly.com/" target=_blank>
http://conferences.oreilly.com</A><BR>
</td></tr>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
<tr><td valign=top>
<b>10th USENIX Security Symposium</b><BR>
<td valign=top>August 13-17, 2001<BR>Washington, D.C.<BR>
<A HREF="http://www.usenix.org/events/sec01/" target=_blank>
http://www.usenix.org/events/sec01/</A><BR>
</td></tr>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
<tr><td valign=top>
<b>HunTEC Technology Expo & Conference</b><br>Hosted by Hunstville IEEE<BR>
<td valign=top>August 17-18, 2001<BR>Huntsville, AL<BR>
URL unkown at present<br>
</td></tr>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
<tr><td valign=top>
<b>Computerfest</b><BR>
<td valign=top>August 25-26, 2001<BR>Dayton, OH<BR>
<A HREF="http://www.computerfest.com/" target=_blank>
http://www.computerfest.com</A><BR>
</td></tr>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
<tr><td valign=top>
<b>LinuxWorld Conference & Expo</b><BR>
<td valign=top>August 27-30, 2001<BR>San Francisco, CA<BR>
<A HREF="http://www.linuxworldexpo.com" target=blank>
http://www.linuxworldexpo.com</A><BR>
</td></tr>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
<tr><td valign=top>
<b>Red Hat TechWorld Brussels</b><BR>
<td valign=top>September 17-18, 2001<BR>Brussels, Belgium<BR>
<A HREF="http://www.europe.redhat.com/techworld" target=_blank>
http://www.europe.redhat.com/techworld</A><BR>
</td></tr>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
<tr><td valign=top>
<b>The O'Reilly Peer-to-Peer Conference</b><BR>
<td valign=top>September 17-20, 2001<BR>Washington, DC<BR>
<A HREF="http://conferences.oreilly.com/p2p/call_fall.html"
target=_blank>
http://conferences.oreilly.com/p2p/call_fall.html</A><BR>
</td></tr>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
<tr><td valign=top>
<b>Linux Lunacy<br>Co-Produced by <i>Linux
Journal</i> and Geek Cruises</b><BR>
<A HREF="http://www.linuxjournal.com/lunacy/cruise.html" target=_blank>
Send a Friend <i>LJ</i> and Enter to Win a Cruise!</A><BR>
<td valign=top>October 21-28, 2001<BR>Eastern Caribbean<BR>
<A HREF="http://www.geekcruises.com/" target=_blank>
http://www.geekcruises.com</A><BR>
</td></tr>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
<tr><td valign=top>
<b>LinuxWorld Conference & Expo</b><BR>
<td valign=top>October 30 - November 1, 2001<BR>Frankfurt, Germany<BR>
<A HREF="http://www.linuxworldexpo.de" target=_blank>
http://www.linuxworldexpo.de</A><BR>
</td></tr>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
<tr><td valign=top>
<b>5th Annual Linux Showcase & Conference</b><BR>
<td valign=top>November 6-10, 2001<BR>Oakland, CA<BR>
<A HREF="http://www.linuxshowcase.org/" target=_blank>
http://www.linuxshowcase.org/</A><BR>
</td></tr>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
<tr><td valign=top>
<b>Strictly e-Business Solutions Expo</b><BR>
<td valign=top>November 7-8, 2001<BR>Houston, TX<BR>
<A HREF="http://www.strictlyebusinessexpo.com/" target=_blank>
http://www.strictlyebusinessexpo.com</A><BR>
</td></tr>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
<tr><td valign=top>
<b>LINUX Business Expo</b><BR>Co-located with COMDEX<br>
<td valign=top>November 12-16, 2001<BR>Las Vegas, NV<BR>
<A HREF="http://www.linuxbusinessexpo.com" target=_blank>
http://www.linuxbusinessexpo.com</A><BR>
</td></tr>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
<tr><td valign=top>
<b>15th Systems Administration Conference/LISA 2001</b><BR>
<td valign=top>December 2-7, 2001<BR>San Diego, CA<BR>
<A HREF="http://www.usenix.org/events/lisa2001/" target=_blank>
http://www.usenix.org/events/lisa2001</A><BR>
</td></tr>
<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>
</table>
<!-- *** END events table [this line needed by Linux Gazette events.py *** -->
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Making Kernel Configuration (More) Fun
</FONT>
</H3>
<P> In a move sure to warm the hearts of those who believe in Linux
Gazette's motto of "making Linux just a little bit more fun!",
Eric Raymond has added a new interface to the Linux kernel configuration
system. This one is reminiscent of Zork and those adventure games:
<P> <PRE>
Welcome to CML2 Adventure, version 1.6.1.
You are in a maze of twisty little Linux kernel options
menus, all different.
<P> The main room. A sign reads `Linux Kernel Configuration
System'. Passages lead off in all directions.
<BLOCKQUOTE>
<P> n
</BLOCKQUOTE>
The arch room. A sign reads `Processor type'.
A passage leads upwards.
<P> Choose your processor architecture.
A brass lantern is here.
There is a row of buttons on the wall of this room.
They read:
X86, ALPHA, SPARC32, SPARC64, MIPS32, MIPS64, PPC,
M68K, ARM, SUPERH, IA64, PARISC, S390, S390X, CRIS
The button marked X86 is pressed.
</PRE>
<P> Courtesy Linux Weekly News.
A copy of Eric's original e-mail is
<A HREF="http://lwn.net/2001/0621/a/kernel-adventure.php3">here</A>.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Tridia
</FONT>
</H3>
<P> <a href="http://www.tridiavnc.com">Tridia Corporation</a>
has an ambitious marketing plan that pits its open
source remote access hybrids head to head with industry leader Symantec.
This is the beginning of a strategic marketing campaign to introduce the
logical benefits of Tridia Corporation's open source hybrids over its closed
source competitors.
Among other platforms, TridiaVNC runs on Linux, and is a useful eSupport tool
for Linux, in particular in mixed OS environments.
Three announcements are planned beginning with a FREE TridiaVNC (virtual
network computing) downloads promotion that's linked to a
<a href="http://www.tridiavnc.com/econtest1">contest</a>.
The TridiaVNC econtest runs for 180 days, from 5/23/01 thru 11/23/01.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Linux in Life Sciences
</FONT>
</H3>
<a href="http://www.ibm.com/">IBM</a> is aiming to use integrated
Linux-based technologies enable
<a href="http://www.ibm.com/solutions/lifesciences">life sciences</a>
companies to
speed the process of managing and sharing the staggering amounts of
data being generated by contemporary research in experimental biology.
<P> On May 29th, IBM and
<a href="http://www.devgen.com/devpage/intro/framejump.html">
Devgen</a>, a
Belgium-based biotechnology company, announced an agreement to deploy IBM
technology and Linux solutions to accelerate the drug development process.
Devgen's informatics system includes a Linux supercluster, consisting of 20
IBM eServer xSeries servers and 2 pSeries servers. The high-performance
system will conduct genetic research on a microscopic roundworm (C. elegans)
to identify validated drug targets and in vivo active compounds. By studying
this transparent worm, Devgen researchers can better understand gene
interactions in humans that trigger chemical reactions in cells and cause
diseases, and narrow the search for medical treatments.
<P> Linux is a key factor in solving a variety of demanding life sciences
challenges, including: Unravelling protein interactions - protein function
is one of the most computationally intensive problems in the world of
research today. Deciphering the interaction of more than one million
proteins requires 1,000 times more compute power and generates 100 times
more data. Understanding protein folding - the way proteins fold into
geometrical shapes allows them to perform their biological functions. It
would take around 300 years, using today's most powerful computer, to
calculate the folding process for even a very small protein. High
performance Linux computing power allows researchers to unravel the protein
folding process. Drug discovery and development process - new drugs often
cost upwards of $500 million to develop and test, and between ten and
fifteen years to approve. New information technologies like Linux are
rapidly becoming a major factor in reducing these costs.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Linux NetworX Announces Support For AMD's Multiprocessor
Architecture
</FONT>
</H3>
<P><a href="http://www.linuxnetworx.com/">Linux NetworX</a>,
a leading provider of powerful and
easy-to-manage Linux cluster computing solutions, announced today support
through its
<a href="http://www.linuxnetworx.com/products/evolocity_amdmp.html">
Evolocity</a> cluster systems for the new
<a href="http://www.amd.com/">AMD</a> Athlon MP
processor and the AMD-760 MP multiprocessing chipset.
Evolocity is a cluster solution, which
incorporates computational hardware with Linux NetworX cluster management
software called ClusterWorX.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">GNU-Linuxfest
</FONT>
</H3>
Galax, Virginia, will host the third annual
<a href="http://www.gnu-linuxfest.com">
Linuxfest</a> on July 14, 2001.
Linuxfest has traditionally celebrated Linux, the alternative operating
system.
Linuxfest this year will offer entertainment, food and Linux related
demonstrations which include Satellite Internet and the new Mandrake OS, as
well as servers, KDE, Gnome, Afterstep, Quick Cams and audio recording.
There will be space to sell and swap and some great door prizes. This
year's Linuxfest will be held on Grayson Street in Galax; and will be the
first street fest in the history of the event.
Attendees may register at the event's website at
<a href="http://www.gnu-linuxfest.com">
www.gnu-linuxfest.com</a>.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Freenet
</FONT>
</H3>
<I>Linux Journal</I> has an
<a href="http://www2.linuxjournal.com/cgi-bin/frames.pl/articles/culture/0027.html">
article</a> about
<a href="http://freenetproject.org/">freenet</a>.
The <a href="http://freenetproject.org/index.php?page=faq">
Freenet FAQ</a> has further information.
Freenet is a network application for sharing information (like the Web),
but without using centralised servers (like Usenet or Gnutella). The
upshot is that on Freenet it's difficult for governments and free-speech
haters to track where the information resides, who inserted it, and
who's requesting it.
The application is still in its alpha stage; many features are still in
the discussion or research stages.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">"Linux 3D Graphics Programming" Book Available
</FONT>
</H3>
<P> The book
<a href="http://linux3dgraphicsprogramming.org/book.shtml">
Linux 3D Graphics Programming</a> is now available for purchase.
The book aims to give a reader who has little or no 3D graphics experience,
a well-rounded understanding of the fundamental theoretical and practical
concepts involved in programming real-time 3D graphics applications using
freely available tools under Linux. Topics include the X Window System,
OpenGL/Mesa, 2D screen access and rasterization, hardware acceleration, and
3D vision and perception. A
tutorial explains how to create 3D models using Blender, a 3D modeller
included on the companion CD.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">UKLinux ISP
</FONT>
</H3>
<P><a href="http://www.uklinux.net/">uklinux.net</a>
is a free (no subscription charges) Linux ISP for the UK. The service
features include:
<P> <ul>
<li>
Unlimited access for both modem and ISDN users with speeds up to 128kb/s</li>
<li>
Unlimited e-mail addresses in the form anything@username.uklinux.net</li>
<li>
20MB of PHP and Perl enabled web space at www.username.uklinux.net</li>
<li>
MySQL or PostgreSQL database facilities</li>
<li>
Local lists of UK
<a href="http://www.uklinux.net/lugs/">Linux User Groups</a>,
a
<a href="http://tucows.uklinux.net">Local Tucows LinuxBerg mirror</a>,
and
Local <a href="http://mirror.uklinux.net">mirrors</a> of the most popular
Linux <a href="http://www.uklinux.net/distributions">Distributions</a></li>
<li>
<a href="http://www.uklinux.net/hotshops">Hot Shops</a> - a listing of
the best commercial suppliers of products and services for Linux</li>
</ul>
Services such as
mail and FTP access are conditional upon accessing the Internet via
uklinux's dial in access numbers which are charged at UK local rate.
If you want to access your e-mail, or FTP your site via another ISP
you will need to upgrade your membership.
<p>Also, all the profits from uklinux go to funding Open Source/Free Software.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green"><I>Linux Journal</I> web articles
</FONT>
</H3>
<P> These articles are available at the <A HREF="http://www.linuxjournal.com/">
<I>Linux Journal</I> web site</A>; they are not in the magazine. (You can also
go to the <A HREF="http://noframes.linuxjournal.com/">no-frames site</A> if you
don't like frames or want minimal graphics.)
<UL>
<LI> "Tux Knows It's Nice to Share" by Marcel Gagn&eacute;.
Tips and more tips on sharing files and print jobs between users and computers.
Includes Samba and other services.
<A HREF="http://noframes.linuxjournal.com/articles/sysadmin/0051.html">Part 1.</A>
<A HREF="http://noframes.linuxjournal.com/articles/sysadmin/0052.html">Part 2.</A>
<A HREF="http://noframes.linuxjournal.com/articles/sysadmin/0053.html">Part 3.</A>
<A HREF="http://noframes.linuxjournal.com/articles/sysadmin/0054.html">Part 4.</A>
<A HREF="http://noframes.linuxjournal.com/articles/sysadmin/0055.html">Part 5.</A>
<A HREF="http://noframes.linuxjournal.com/articles/sysadmin/0056.html">Part 6.</A>
<A HREF="http://noframes.linuxjournal.com/articles/sysadmin/0057.html">Part 7.</A>
<A HREF="http://noframes.linuxjournal.com/articles/sysadmin/0058.html">Part 8.</A>
<P>
<LI> "Your Network's Secret Life" by Marcel Gagn&eacute;.
What's happening out there over your twisted pair cabling that you don't know
about?
<A HREF="http://noframes.linuxjournal.com/articles/sysadmin/0059.html">Part 1.</A>
<A HREF="http://noframes.linuxjournal.com/articles/sysadmin/0060.html">Part 2.</A>
<P>
<LI> "Gratuitous Window Dressing" by Marcel Gagn&eacute;. Stupid and
not-so-stupid tricks for your GUI session.
<A HREF="http://noframes.linuxjournal.com/articles/sysadmin/0046.html">Part 1.</A>
<A HREF="http://noframes.linuxjournal.com/articles/sysadmin/0047.html">Part 2.</A>
<A HREF="http://noframes.linuxjournal.com/articles/sysadmin/0048.html">Part 3.</A>
<A HREF="http://noframes.linuxjournal.com/articles/sysadmin/0050.html">Part 4.</A>
<P>
<LI>
<A HREF="http://noframes.linuxjournal.com/articles/culture/0026.html">"Open-Source Gaming for Linux"</A> by J Neil Doane. <P>
<LI> <A HREF="http://noframes.linuxjournal.com/articles/currents/0031.html">
"Linux on the Desktop--an Impossible Dream?"</A> by Bryan Pfaffenberger. <P>
<LI><A HREF="http://noframes.linuxjournal.com/articles/currents/0030.html">
"Why Open Content Matters"</A> by Bryan Pfaffenberger. With the
increasingly complicated copyright laws surrounding media, open
media--like open source--may be the only way people can access these
types of materials in the future. Bryan begins a
three-part discussion by laying out the future and looking at the
past. <P>
<LI><A HREF="http://noframes.linuxjournal.com/articles/linux_review/0047.html">
"Book Review: Python Standard Library"</A> by Phil Hughes. <P>
<LI> <A HREF="http://noframes.linuxjournal.com/articles/business/0040.html">
"Open Source Opens Doors for Developers"</A> by Bob Gilbert. The
combination of PostgreSQL and PHP can be a powerful way to help all
levels of business gather information and actually put it to work in
beneficial ways. Bob Gilbert of Great Bridge shares the story of one
company that took the plunge. <P>
<LI> <A HREF="http://noframes.linuxjournal.com/articles/misc/0043.html">
"Sendmail Setup for Your Home Network"</A> by Jhon H Caicedo O. <P>
<LI> <A HREF=" http://noframes.linuxjournal.com/articles/misc/0046.html">
"Debian Package Management, Part 2: a Developer's Guide"</A> by David
Blackman. How to make your own .deb files, and how to use the 'equivs' package
to tell Debian about your locally-built program. <P>
</UL>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green"><IMG ALT="Linux Focus" SRC="../gx/linuxfocus.jpg" WIDTH="143" HEIGHT="45">
</FONT>
</H3>
The following articles are in the July-August issue of the multilingual
ezine <A HREF="http://www.linuxfocus.org/">Linux Focus</A>.
<br>
<UL>
<LI><a href="http://linuxfocus.org/English/July2001/article148.shtml">Yellow Pages, part 1</a><br></LI>
<LI><a href="http://linuxfocus.org/English/July2001/article162.shtml">Yellow Pages 2 : The client side</a><br></LI>
<LI><a href="http://linuxfocus.org/English/July2001/article170.shtml">Learning with nmap</a><br></LI>
<LI><a href="http://linuxfocus.org/English/July2001/article191.shtml">Avoiding security holes when developing an application - Part 4: format
strings</a><br></LI>
<LI><a href="http://linuxfocus.org/English/July2001/article207.shtml">Singing in the web</a><br></LI>
<LI><a href="http://linuxfocus.org/English/July2001/article208.shtml">Bookreview: Professional Perl Programming</a><br></LI>
<LI><a href="http://linuxfocus.org/English/July2001/article209.shtml">Compiling, Configuring and Installing a fully-working Customized Linux
Kernel</a><br></LI>
<LI><a href="http://linuxfocus.org/English/July2001/article210.shtml">Wacky uses for Raid, /dev/ram, and ramfs</a><br></LI>
<LI><a href="http://linuxfocus.org/English/July2001/article211.shtml">Do magic with images on the shell</a><br></LI>
</UL>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Linux Links
</FONT>
</H3>
<a href="http://www.thedukeofurl.org/">The Duke of URL</a> has posted:
<ul>
<li>A <a href="http://www.thedukeofurl.org/reviews/misc/progeny10">
review</a> of Progeny Debian Linux 1.0
<li>A <a href="http://www.thedukeofurl.org/reviews/misc/distroroundup">
Linux Distribution Round-Up</a> which
attempts to give users the tools to answer the eternal
question of "Which distribution is the best?", as well as general guidelines
on comparing distributions.
<li>DVD on Linux
<a href="http://www.thedukeofurl.org/reviews/misc/dvdlinux">Guide</a>
<li>XFree86 4.1.0
<a href="http://www.thedukeofurl.org/reviews/misc/xfree86410">review</a>
<li>Red Hat Linux 7.1
<a href="http://www.thedukeofurl.org/reviews/misc/redhat71">review</a>
<li>Plextor PlexWriter 16/10/40A
<a href="http://www.thedukeofurl.org/reviews/drives/plexwriter161040a">
review</a>
<li>Linux
<a href="http://www.thedukeofurl.org/reviews/misc/linuxguide11">
Buyer's Guide</a>, version 11
<li>A <a href="http://www.thedukeofurl.org/reviews/misc/deadlinux">
look</a> at many people's perceived fall of Linux on desktop and server
<li>The Duke is also interested in raising awareness of
<a href="http://www.thedukeofurl.org/index.shtml#stealingfromtheduke">
plagiarism</a>.
</ul>
<p>
<a href="http://www.firstlinux.com/">firstLinux.com</a> have a
<a href="http://www.firstlinux.com/articles/chess">review</a>
of Linux chess interfaces.
<p>
Stop the presses! RMS Says
<a href="http://slashdot.org/features/01/05/29/2126224.shtml">
Free Software Is Good</a>. <a href="http://www.slashdot.org/">Slashdot</a>
readers respond "Dog Bites Man", "Sky Blue".
<p>
Asian characters and why Unicode is
<a href="http://www.hastingsresearch.com/net/04-unicode-limitations.shtml">
inadequate</a>
<p>
Linux forklifts in the <a href="http://www.anchordesk.co.uk/anchordesk/commentary/columns/0,2415,7110109,00.html">
data warehouse</a>
<P>
Some more
<a href="http://www.microsoft.com/business/downloads/retail/linux_in_retail_and_hospitality.doc">
FUD</a> from Microsoft (MS Word format).
Courtesy <a href="http://lwn.net/">Linux Weekly News</a>. In a further twist
<a href="http://www.slashdot.org">Slashdot</a> reported that Mr. Bill Gates
believes that
<a href="http://slashdot.org/articles/01/06/20/1249203.shtml">
Linux is a like PacMan</a>.
<p>
Finally, another <a href="http://www.slashdot.org">Slashdot</a> story,
looking at David A. Wheeler's analysis of the true size of Linux. See the
reaction <a href="http://slashdot.org/articles/01/06/21/0123250.shtml">
here</a>
<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">SAP and Linux on the ZSeries
</FONT>
</H3>
<P> <a href="http://www.macro4.com/">Macro 4</a>
has announced support
for Linux on the new S/390 eServer ZSeries for its SAP certified output
management solution. By running Macro 4's solution with SAP and Linux on the
IBM platform, users can take advantage of the space, energy and cost savings
of the latest e-business mainframe technology and be assured of dependable
output across a distributed network.
Large SAP implementations require many SAP application servers and it is not
atypical for a sizeable company to run as many as 150 instances of SAP at
once. Organisations can simplify their IT systems by moving the SAP
application servers to one ZSeries box with each application running on an
instance of Linux. But they still have to manage output from all of these
applications. UniQPrint gives users a single point of control for
cross-platform enterprise printing from an IBM eServer ZSeries platform
running Linux and assures the delivery of documents from point of origin to
any output destination, be it print, fax, e-mail, or Web site.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Workstation Solutions Announces New Quick Restore Data Protection Software for Linux Users
</FONT>
</H3>
<P><a href="http://www.worksta.com">Workstation Solutions</a>
have announced new Linux and Windows platform
support for its Quick Restore backup and recovery software. This broadened
platform support extends the quick implementation, easy operation, and
comprehensive scope of Quick Restore across Microsoft Windows 2000, UNIX,
and Linux operating environments. The company also announced new Quick
Restore features to improve performance, extend firewall support, control
DLT tape format, and support newly available tape libraries from leading
vendors.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">mnoGoSearch Search Engine Version 3.1.14 Released
</FONT>
</H3>
The new version 3.1.14 of
<a href="http://www.mnogosearch.org/">
mnoGoSearch</a> free Open Source search
engine software for intranet and web servers is available from
mnoGoSearch website.
With the new version the 3.1.x branch is declared stable and it
includes various enhancements and fixes,
as documented in the
<a href="http://www.mnogosearch.org/history.html">ChangeLog</a>.
mnoGoSearch runs on Linux and other *nix OS'es.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Micro Sharp Technology: Netule
</FONT>
</H3>
<P><a href="http://www.netule.com/">Micro Sharp Technology</a>, a
provider of thin server solutions have announced the release of Netule Web
Module I (WM-I) and Netule eMail Module I (EM-I).
EM-I and WM-I are based on Linux, an extremely powerful, stable and reliable
UNIX like operating system. Linux is easy to upgrade and offers a true
multi-tasking solution.
EM-I is a robust, thin server solution that allows
users to simply, predictably and cost effectively meet eMail server needs
in a shorter period of time.
WM-I is intended to meet users' web server requirements in a similar
manner. Each module comes with all the hardware and software needed to plug
in and get started.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
<FONT COLOR="green">Other Software
</FONT>
</H3>
<P>Internet Exchange Messaging Server (IEMS) 5, the
latest messaging solution from developer
<a href="http://www.ima.com">
International Messaging Associates</a>,
will be released June 12, 2001.
IEMS 5 runs on Linux Red Hat, Caldera, VA Linux,
Turbo Linux Server, Suse, Mandrake, and Windows 98, Windows 2000, and
Windows NT.
<hr noshade, width="20%">
<P>
<a href="http://www.aladdinsys.com/">
Aladdin Systems</a>, have
announced a new licensing initiative - the
<a href="http://www.stuffit.com/">StuffIt OneSource</a>
Volume License Program. StuffIt
natively supports Macintosh, Windows, Linux and Solaris Unix
platforms. With StuffIt, users can choose to easily manage their
favourite file types, such as .zip, .sit, .rar, .tar, .gzip and many
others.
<hr noshade, width="20%">
<P>
<a href="http://www.amsrealtime.com/">Advanced Management Solutions</a>,
supplier of tools for project and resource
management claim that AMS Realtime is the first and only non-browser based
Project Management software available for Linux. This software is a Linux
port of Advanced Management Solutions' application AMS REALTIME Projects.
LINUX users can now try out this fully functional Linux version through a
special free trial offer.
<!-- *** BEGIN copyright *** -->
<P> <hr> <P>
<H5 ALIGN=center>
Copyright &copy; 2001, 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 68 of <i>Linux Gazette</i>, July 2001</H5>
<!-- *** END copyright *** -->
<!-- ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: -->
<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, Breen, Chris, and the Gang,
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>
<p><em><font color="#990000">There is no guarantee that your questions
here will <b>ever</b> be answered. Readers at confidential sites
must provide permission to publish. However, you can be published
anonymously - just let us know!
</font></em></p>
</center>
<p><hr><p>
<H3>Contents:</H3>
<dl>
<dt><a href="#tag/greeting"
><strong>&para;: Greetings From Heather Stern</strong></A>
<dt><a href="tag/bios.html"
><strong>!!: Meet The Answer Gang</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>Dial-on-demand users should know:</strong></a>
<dt><A HREF="#tag/2"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>XFS ....font server...true font</strong></a>
<dt><A HREF="#tag/12"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>A tired Newbie attempts Linux (again)</strong></a>
<dt><A HREF="#tag/3"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
></a>I've had no response to a long letter of several weeks ago!? --or--
<dd><A HREF="#tag/3"
><strong>Sometimes, we just don't know what to say</strong></a>
<dt><A HREF="#tag/4"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
></a>I need a windows-linux solution --or--
<dd><A HREF="#tag/4"
><strong>Bulk File Transfers from Windows to ???</strong></a>
<dt><A HREF="#tag/5"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>Cannot Login Question</strong></a>
<dt><A HREF="#tag/6"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>LG 24 - Tips: Yet another way to find</strong></a>
<dt><A HREF="#tag/7"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
></a>Deleting a file that thinks it is an option --or--
<dd><A HREF="#tag/7"
><strong>Dash it All! Coping with ---Unruly--- Filenames</strong></a>
<dt><A HREF="#tag/8"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
></a>aol instant messanger behind lrp (linux router project) box --or--
<dd><A HREF="#tag/8"
><strong>File Tranfers with AIM (AOL Instant Messenger)</strong></a>
<dt><A HREF="#tag/9"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>reverse dns</strong></a>
<dt><A HREF="#tag/10"
><img src="../gx/dennis/qbub.gif" height="28" width="50"
alt="(?)" border="0"
><strong>Closing Ports</strong></a>
<dt><A HREF="#tag/11"
><img src="../gx/dennis/bbub.gif" height="28" width="50"
alt="(!)" border="0"
><strong>Best of ISO burning under Windows.</strong></a>
<dt><A HREF="#tag/12"
><img src="../gx/dennis/bbub.gif" height="28" width="50"
alt="(!)" border="0"
><strong>A tired Newbie attempts Linux (again)</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>
Greetings, dear readers, and welcome to another exciting installment of
The Answer Gang.
</p>
<p>
One of our crew has come up with an amusing bit of text to send to people
who are amazingly off topic, for example, completely non-computing matters:
</p>
<blockquote>
<a href="misc/tag/droids.txt"
>These Are Not The Droids You're Looking For</a>
</blockquote>
<p>
It gave me a belly laugh when I first saw it. Some who get this <em>are</em>
asking computer questions, tho - solely about a certain Other OS. Perhaps
amazingly, a few of the Gang don't mind working with MSwin. And certainly
questions about mixing two or more operating systems are juicy and we love
answering those (if we actually <em>can</em>) but this just isn't the place for
a question that would be answered much better at the Win98 Megasite:
</p>
<blockquote>
<a href="http://www.cmpnet.com/win98"
>http://www.cmpnet.com/win98</a>
</blockquote>
<p>
Oddly enough I don't think I've seen any MacOS questions roll through. But
these sort of notes happen often enough that I've got my own little
"answering machine style" note:
</p>
<blockquote>
<a href="misc/tag/youve-reached.txt"
>You've Reached The Linux Gazette Answer Gang</a>
</blockquote>
<p>
If that's the only peeve we have left I think we're doing alright. Now
for stuff that's about our favorite penguin playground - Linux!
</p>
<p>
As it's been around a while and many of the commercial distros are
releasing their new versions with 2.4 kernels and various modern bugfixes,
I know an increasing number of truly Newbie users who are taking the plunge.
Given the context I know them from, they're not generally dumb people, but
they have been led to believe that the hassle of a full install will be
worth it for the security they will gain.
</p>
<p>
Unfortunately, the gain doesn't happen automagically. Okay, the average
setup is a little better out of the box than Windows. But it's like buying
a car with a car alarm and other "smart sensors" -- they're no good if you
can't find the clicker to turn them on. Or if you can turn on the alarm
but not roll up the windows and close the convertible top.
</p>
<p>
Or if you find the clicker covered with cryptic phrases like "IPchains"
and "construct a filter to block UDP..." This is nonsense to a lot of
people. There are tools which claim to help toughen it up, except that
if they don't explain what they're doing, you have no idea what they helped,
or whether they are hindering something that you actually need to do.
</p>
<p>
Beyond that, there's simply that anything that had to go through the
publishing industry is out of date. Your boxed distro may have taken a
month and a half to hit the shelves - while they're proud of getting 2.4.2
in there, 2.4.5 is already released and pre6 is cooking along. And so on.
If you don't make arrangements to update to the security patch versions
as soon as you're a working system, you'll be wide open to something.
</p>
<p>
Pleasantly, tools to help people tweak firewall rules are actually starting
to get usable. Distros increasingly resist, or have ways of tracking, suid
binaries - which are dangerous not so much because of that feature, as that
they are almost always suid root, the most dangerous account on the system.
Distros make it increasingly easy to always get the latest, and the major
ones seem to have websites where you can keep an eye on how they're doing.
</p>
<p>
So as we approach Independence Day -- which in the U.S. is a celebration
of determining our own destiny -- take a few thoughts towards those unknown
souls who set the first policies you depend on, and towards your own ability
to choose how you are defended. The price of liberty... is eternal vigilance.
</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"
>Dial-on-demand users should know:</H3>
<p><strong>From Richard Greaney
</strong></p>
<p align="right"><strong>More Answers by Mike Orr, Jim Dennis,
Willy Tareau, David Forrest, Juanjo and Erik Corry
<br></strong></p>
<!-- sig -->
<P><STRONG>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
If you are on a dial-up connection and are tired of not getting reliable
starts to your connection (often having to click "refresh" after
starting a browser to prevent it from timing out) you may benefit from
this piece of advice.
</STRONG></P>
<P><STRONG>
There are two ways Linux looks up a host before connecting. One uses the
traditional <TT> gethostbyname()</TT> function (which uses DNS and hence UDP)
while the other uses a straight lookup on the IP address. Either way, if
you use a demand dial setup, these will run into problems. If you type
ifconfig before you get connected, you will notice your ppp0 adapter has
the address 10.64.64.64. Once you are connected, it becomes a little
more beleivable. However, those first lookup SYN packets are sent from
10.64.64.64, but since the ppp interface has changed it's IP address,
the packets will not reach it. Refreshing the connection attempt will
work, but it's less than elegant.
</STRONG></P>
<P><STRONG>
How to fix:
cat <TT>/proc/sys/net/ipv4/ip_dynaddr</TT> should return the value '1'. If this
is not the case, type (as root) echo 1 &gt; <TT>/proc/sys/net/ipv4/ip_dynaddr</TT>
</STRONG></P>
<P><STRONG>
What you are doing is telling your machine that it has a dynamic IP
address. Any packets which are originally sent from 10.64.64.64 will be
redirected to the new IP address as soon as you get connected to your ISP.
</STRONG></P>
<P><STRONG>
Richard Greaney
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Thanks for the advice. Why do people need to do this now? When I used
to have a dynamic IP address three years ago, I never needed to do this.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
That one I can't answer. I've built a few Linux boxes in my time and not
one of them has had anything other than 0 set for the ip_dynaddr field.
Having said that, they were very seldom used to connect to the net. My
present machine (which connects to the net several times a day) was also
set to 0 by default (as is standard) but I decided one day I was going
to iron out why I was having to refresh the connection on startup before
any data came across. I was looking to rewrite some source code but
stumbled across this one instead. I've read that Linux is widely known
for not being great with demand-dial setups. Perhaps this is why? I
thought the people could benefit from knowing this.
</STRONG></P>
<P><STRONG>
The text from the kernel docs explains it pretty clearly.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [JimD]
The result is a failure of <EM>existing</EM> connections. As new connections
are established over the newly raised link, those work. So the
ip_dynaddr solution is for a problem that many Linux users never knew
they were having.
</BLOCKQUOTE>
<BLOCKQUOTE>
Paul Mackerras (author/maintainer of the Linux pppd) was trying to
explain this whole thing to me one time. I'm afraid I just wasn't
"getting it." (We'd probably already had too much sake by then,
I think we were eating sushi that evening).
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
I did a google search for "ip_dynaddr" and came up with:
</BLOCKQUOTE>
<blockQuote>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> (Willy Tareau)
<DL>
<DT><A HREF="http://web.gnu.walfield.org/mail-archive/linux-kernel/2000-March/0179.html"
>http://web.gnu.walfield.org/mail-archive/linux-kernel/2000-March/0179.html</A>
<dd>
What exactly does setting ip_dynaddr to 1 or 2 do? it allows to change your
local addresses to the one of an interface which is changing (typically ppp*)
when up.
</DL></blockQuote>
<blockQuote>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
(David Forrest)
<DL>
<DT><A HREF="http://web.gnu.walfield.org/mail-archive/linux-kernel/2000-March/0184.html"
>http://web.gnu.walfield.org/mail-archive/linux-kernel/2000-March/0184.html</A>
<dd><code>drf5n@mug:/usr/src/linux$ grep -r ip_dynaddr * </code>
</DL></blockQuote>
<blockQuote>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> (Juanjo, with RST-provoking mode by Erik Corry )
<DL>
<DT><A HREF="http://www.linuxhq.com/kernel/v2.0/doc/networking/ip_dynaddr.txt.html"
>http://www.linuxhq.com/kernel/v2.0/doc/networking/ip_dynaddr.txt.html</A>
<dd>
<strong>IP dynamic address hack-port v0.03-rst</strong>
<br>
This stuff allows diald ONESHOT connections to get established by
dynamically changing packet source address (and socket's if local procs).
It is implemented for TCP diald-box connections(1) and IP_MASQuerading(2).
<br>&nbsp;<br>
If enabled[*] and forwarding interface address has changed:
<br>&nbsp;<br>
<ul>
<LI>Socket (and packet) source address is rewritten ON RETRANSMISSIONS
while in SYN_SENT state (diald-box processes).
<LI>Out-bounded MASQueraded source address changes ON OUTPUT (when
internal host does retransmission) until a packet from outside is
received by the tunnel.
</ol>
<br>
This is specially helpful for auto dialup links (diald), where
the &quot;actual&quot; outgoing address is unknown at the moment the
link is going up. So, the <EM>same</EM>
(local AND masqueraded) connections requests that bring the link up will be
able to get established.
<br>&nbsp;<br>
If you enable the RST-provoking mode, then the source address will be changed,
even if the socket is established. This means we send an incorrect packet out,
which causes the remote host to kill our socket. This is the desired behaviour,
because such a socket is doomed anyway, and the earlier it dies, the better.
This prevents the dial-on-demand connection from being kept up by a dead
connection, and tells the application that the connection was lost.
<br>&nbsp;<br>
[*] At boot, by default no address rewriting is attempted.
<br>&nbsp;<br>
The values for the ip_dynaddr sysctl are:
<br>&nbsp;<br>
<code><font color="#000033"><br> 1: To enable:
<br> 2: To enable verbosity:
<br> 4: To enable RST-provoking:
</font></code>
<br>&nbsp;<br>
Flags can be combined by adding them. Common settings
would be:
<dl>
<dt>
To switch off special handling of dynamic addresses (default)
<dd><CODE>
# echo 0 &gt; /proc/sys/net/ipv4/ip_dynaddr
</CODE>
<dt>
To enable rewriting in quiet mode:
<dd><CODE>
# echo 1 &gt; /proc/sys/net/ipv4/ip_dynaddr
</CODE>
<dt>
To enable rewriting in verbose mode:
<dd><CODE>
# echo 3 &gt; /proc/sys/net/ipv4/ip_dynaddr
</CODE>
<dt>
(for backwards compatibility you can also use)
<dd><CODE>
# echo 2 &gt; /proc/sys/net/ipv4/ip_dynaddr
</CODE>
<dt>
To enable quiet RST-provoking mode:
<dd><CODE>
# echo 5 &gt; /proc/sys/net/ipv4/ip_dynaddr
</CODE>
<dt>
To enable verbose RST-provoking mode:
<dd><CODE># echo 7 &gt; /proc/sys/net/ipv4/ip_dynaddr
</CODE>
</dl>
</DL></blockQuote>
<!-- end 1 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/2"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 2 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>XFS ....font server...true font</H3>
<p><strong>From Hari Charan Meda
</strong></p>
<p align="right"><strong>Answered By Huibert Alblas
<br></strong></p>
<P><STRONG>
hi
</STRONG></P>
<P><STRONG>
how do i install XFS font server on Red HAT 7.1.i need to install true font
on my machine.
</STRONG></P>
<P><STRONG>
need help
<IMG SRC="../gx/dennis/unsmily.gif" ALT=":("
height="24" width="20" align="middle">
</STRONG></P>
<P><STRONG>
harry
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Halb]
Hi,
</BLOCKQUOTE>
<BLOCKQUOTE>
As far as I know xfs is allready installed on RedHat distro's from 6.2
and up. But there are not many TTF installed, so you have to 'install'
them seperatly.
Going to www.redhat.com, clicking on 'support' and searching for 'fonts'
results in: <A HREF="http://www.redhat.com/support/alex/215.html"
>http://www.redhat.com/support/alex/215.html</A> which is a
fairly short intro into adding extra TTF. It should work that way,
if somehow xfs is not installed, the rpm should be on your redhat cd.
</BLOCKQUOTE>
<BLOCKQUOTE>
Watch out for these tripwires (cavcats or something they are called here
on the list...):
</BLOCKQUOTE>
<blockQuote><ul>
<LI>_no_ capital letters in the fontnames.
<LI>corect usage of ttmkfdir
<LI>correctly setting up XF86Config
</ul></blockQuote>
<BLOCKQUOTE>
A search on www.google.com/linux for 'ttf redhat howto' returned(among
others):
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQuote>
<A HREF="http://www.ibiblio.org/pub/Linux/docs/HOWTO/mini/other-formats/html_single/FDU.html#INTRO"
>http://www.ibiblio.org/pub/Linux/docs/HOWTO/mini/other-formats/html_single/FDU.html#INTRO</A>
</BLOCKQuote></BLOCKQUOTE>
<BLOCKQUOTE>
or of course the linuxgazette search engine came up with this:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQuote>
<A HREF="../issue28/ayers1.html"
>http://www.linuxgazette.com/issue28/ayers1.html</A>
</BLOCKQuote></BLOCKQUOTE>
<BLOCKQUOTE>
Have fun reading the documentation.
</BLOCKQUOTE>
<!-- end 2 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<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"
>A tired Newbie attempts Linux (again)</H3>
<p><strong>From Paul Bussiere
</strong></p>
<p align="right"><strong>Answered By Mike Orr, Jim Dennis
<br></strong></p>
<blockquote><font color="#000066"><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather] Last month Paul Bussiere wrote in with a submission that raised a valid
point, which I published in The Mailbag
(<A HREF="../issue67/lg_mail67.html#mailbag/5"
>http://www.linuxgazette.com/issue67/lg_mail67.html#mailbag/5</A>)
and which, pleasantly, has got us a few responses from potential authors.
It mentioned that TAG had some comments for him, and I linked across, but
it had escaped my processing script.
</font></blockquote>
<blockquote><font color="#000066">Not surprisingly a few people mailed him, wondering why we hadn't answered
him. (See this month's <a href="lg_mail68.html">Mailbag</a>.)
While it's certainly true that every month The Answer Gang does send
out answers to a lot more people than you see in print these days, I had
definitely intended to see his thread published.
</font></blockquote>
<blockquote><font color="#000066">So here it is -- my apologies for the confusion.
</font></blockquote>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Of all the articles I have read on how wonderful Linux is, seldom have I
seen any that [cynically] document how the average Windows user can go from
mouse-clicking dweeb to Linux junkie.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Have you read The Answer Gang column? It's choc-full of problems people
have installing and using Linux, and should be a dose of reality for
anybody thinking that going from Win to Lin requires no effort. Occasionally
we run pieces about things to watch out for when doing your first Linux
install.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
So, the claim of FREE FREE FREE really isn't so....I've found other places
that you can buy a CD copy cheaper but still, some money negates the FREE.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Most experienced Linuxers would caution a new user against downloading
the OS the first time or getting a $5 CD from Cheap Bytes. The cost of
a commercial distribution with a detailed tutorial and reference manual
is quite worth it, compared to spending a weekend (or two) getting it right.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Why
doesn't Linux do the equivalent of a DOS PATH command? Newbie Me is trying
to shutdown my system and I, armed with book, type "shutdown -h now" and am
told 'command not found'. But wait, my book says...etc etc....and of
course, I now know you have to wander into sbin to make things happen. Why
such commands aren't pathed like DOS is beyond me....perhaps that's another
HowTo that has eluded me.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Linux does have commands for querying and setting the path.
</BLOCKQUOTE>
<BLOCKQUOTE><pre>
$ echo $PATH
/usr/bin:/bin:/usr/X11R6/bin:/usr/games:.
$ PATH=/home/me/bin:$PATH
$ echo $PATH
/home/me/bin:/usr/bin:/bin:/usr/X11R6/bin:/usr/games:.
</pre></BLOCKQUOTE>
<BLOCKQUOTE>
The path is an environment variable like any other environment variable,
so you set it in your shell and it propogates down to all subcommands.
(Actually, that's the way it works in DOS too; DOS just has an extra
convenience command to set it.)
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [JimD]
Actually, technically the way that environment variables and shell
variables work in UNIX is somewhat different than how they work in
DOS' <TT>COMMAND.COM.</TT>
</BLOCKQUOTE>
<BLOCKQUOTE>
In UNIX shell there are variables. These are either shell/local
variables or they are in the "environment." A variable is an
association of a value to a name. They are untyped strings. One can
move a variable from the shell's heap into the environment using the
'export' (Bourne and friends) or the 'setenv' (csh/tcsh) built-in
commands.
</BLOCKQUOTE>
<BLOCKQUOTE>
In either case all that is being done is that the variable and its
value are being stored in different memory regions (segments). Here's
why:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQuote>
When any program is started under UNIX it is done via one of the
exec*() family of system calls. <TT> exec()</TT> replaces the currently running
program with a new one. That is to say that it overwrites the code,
heap and other memory segments of the current process with a new
program (and performs a number of initialization and maintenance
functions that relate to closing any file descriptors that were
marked "close on exec" resetting the signal processing masks, etc).
</BLOCKQuote></BLOCKQUOTE>
<BLOCKQUOTE>
The environment is the one segment that is NOT overwritten during
<TT>exec()</TT>. This allows the process to retain some vestige of its
"former self."
</BLOCKQUOTE>
<BLOCKQUOTE>
Under UNIX all processes are creatd via the <TT> fork()</TT> system call.
(Under Linux <TT> fork()</TT> is a special case of the <TT> clone()</TT> system call
--- but the statement is still "mostly" true). <TT> fork()</TT> creates an
exact copy of a process. Normally the <TT> fork()</TT>'d processes (now there
are two "clones" of one another) immediately go their separate ways.
One of them continues one set of operations (usually the parent) while
the other handles some other jobs (processing a subshell, handling a
network connection/tranaction, or going on to <TT> exec()</TT> a new program).
</BLOCKQUOTE>
<BLOCKQUOTE>
So, a side effect of the environment handling is that a copy of
the environment is passed from a child shell to all of its descendents.
Note: this is a <EM>copy</EM>. The environment is NOT an interprocess
communications mechanism. At least, it is NOT a bidirectional one.
</BLOCKQUOTE>
<BLOCKQUOTE>
(Incidentally any process can also remove items from its environment,
or even corrupt it by scribbling sequences of characters that don't
follow the variable=value\0 convention, using NUL terminated ASCII
strings. Also there are variations of the exec*() system call which
allow a process to specify an alternative block of memory --- a pointer
to a new environment. In this way a process can prepare a completely
new environment for itself).
</BLOCKQUOTE>
<BLOCKQUOTE>
Notice that, in UNIX, the notion of a process persists <EM>through</EM>
the execution of multiple programs. The init process forks
children which <EM>become</EM> (exec) shells to handle startup scripts, and
"getty" processes to handle login requests. the various rc shell
process spawn off childrem which become invocations of external commands
(like mount, fsck, rm, etc). Some of those children set themselves
as "session leaders" (create their own process groups), detach themselves
from the console and "become" various sorts of daemons. Meanwhile the
getty processes "become" copies of login which in turn may become
login shells or which (under other versions of the login suite ---
particularly PAM versions with logout "cleanup" enabled) may spawn
children that become interactive shells.
</BLOCKQUOTE>
<BLOCKQUOTE>
An interactive shell spawns of <EM>many</EM> children. <EM>EVERY</EM> pipe
implicitly creates a subprocess. Every "normal" invocation of an
external command also creates a subprocess (the shell's own
"exec" command being a notable exception, it terminates the shell
causing the current process to "become" a running instance of
some other shell --- in other words the shell "exec" command is a
wrapper around the <TT>"exec()</TT>" system call). Some of the subprocesses
don't perform any <TT> exec()</TT>. These are subshells. Thus a command
like:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQUOTE><CODE>
echo foo | read bar
</CODE></BLOCKQUOTE></BLOCKQUOTE>
<BLOCKQUOTE>
.. from bash will create one subshell (child process) which will
read a value from the pipeline. (It will then simply exit; since
this is a nonsensical example). A command like:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQUOTE><CODE>
/bin/echo foo | { read bar; echo $bar$bar ; }
</CODE></BLOCKQUOTE></BLOCKQUOTE>
<BLOCKQUOTE>
... create <EM>two</EM> children (actually a child and a grandchild).
The child will create a pipe, <TT> fork()</TT>, and then <TT> exec()</TT> the external
version of the echo command. It's child (our shell's grandchild) will
read its pipeline modify its copy of the bar variable, then echo a couple
of copies of that value. Note that we don't know (from these examples)
if bar is a shell/local variable or an environment variable. It doesn't
matter. If the variable was in our shell's environment than the
subshell (the grandchild, in this case) will be modify its copy of that
environment variable. If the variable didn't exist, the subshell will
simply create it as a local variable. If the variable <EM>did</EM> exist as
a shell/local (heap) variable in our shell, it would cease to exist
in the child process after the <TT> exec()</TT> of the <TT>/sbin/echo</TT> command, but
a copy of it would <EM>still</EM> exist (and be overwritten) in the grandchild
process.
</BLOCKQUOTE>
<BLOCKQUOTE>
Meanwhile the original shell process does a <TT>"wait()</TT>" system call
on its child. In other words it just idly sits by until the
work is done, and then it reaps the result codes (the exit values
returned by the suprocesses) and continues.
</BLOCKQUOTE>
<BLOCKQUOTE>
(Incidentally, the fact that the child process is on the "right"
side of these pipe operators is common but not guaranteed. It is the
case for the Bourne and bash shells. However, the opposite case holds
true for newer versions of ksh ('93 or maybe '88 and later?) and zsh;
I personally believe that ksh and zsh is doing "The Right Thing (TM)"
in this regard --- but it is a nitpick).
</BLOCKQUOTE>
<BLOCKQUOTE>
My point here is that the nature of "environment" variables seems to
cause new students of UNIX endless confusion. It's really quite
easy to understand if you think in terms of the underlying <TT> fork()</TT> and
<TT>exec()</TT> operations and how they'll effect a process' memory map.
</BLOCKQUOTE>
<BLOCKQUOTE>
MS-DOS has an "environment" that is similar to the UNIX environment
in that it is a set of variable/name value pairs and that it exists
in a portion of memory that will persist through the execution of
new programs. However MS-DOS doesn't have a <TT>"fork()</TT>" or similar
system call and can't implement pipes as "coprocesses" (with one
process writing into a "virtual file" --- an unnamed file descriptor
that exists purely in memory and never on a real, physical filesystem).
</BLOCKQUOTE>
<BLOCKQUOTE>
(MS-DOS handles pipes by created a temporary file and a "transparent
redirection" executing a writer process, waiting for that to complete
--- writing all its output into the temp file, and then executing a
reader process with transparent input redirection to eat up the
contents of the temp file; and finally executing its own deletion of
the temp file. This is a pale imitation of how UNIX manages pipes).
</BLOCKQUOTE>
<BLOCKQUOTE>
The scary thing about the way that MS-DOS runs these programs
is that it marks some state in one region of memory (part of its
"reserved/resident" memory; then it executes the program). When
the external program exits it passes control back to the command
interpreter's resident portion. The resident portion then
performs a checksum on the "transient portion" of the DOS address
space to determine if that "overlay" needs to be reloaded from the
command interpreter's disk image/file. Then it resumes some of
its state. If it was in the process if executing a batch file
it *re-opens* the file, searches to its previous offset (!) and
resume it's read/parse/execute process.
</BLOCKQUOTE>
<BLOCKQUOTE>
I can imagine that experienced UNIX programmers who were never
tortured with MS-DOS internals or the nitty gritty of CP/M are
cringing in horror at this model. However, it really makes alot of
sense if you consider the constraints under which MS-DOS was hacked
to operate. It was intended to work from floppies (possibly on
systems with a single floppy drive and potentially without any
resident system filesystem). It need to work in about 128K or less
(that's kilobytes) of RAM though it <EM>might</EM> have had as much as 640K
to work with..
</BLOCKQUOTE>
<BLOCKQUOTE>
I guess I get nervous when I see people explaining UNIX semantics
in terms of MS-DOS. I've learned too much about the differences between
them to be comfortable with that --- and I've seen to many ways in
which the analogy can lead to confusion in the UNIX novice. Probably
it's silly of me to nitpick on that and bring up these hoary details.
MS-DOS is almost dead; so it may be that the less people know about
how it worked, the better.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
<TT>/sbin</TT> and <TT>/usr/sbin</TT> should be in the root user's path. If they're not,
adjust <TT>/root/.bash_profile</TT> or <TT>/root/.bashrc.</TT>
</BLOCKQUOTE>
<BLOCKQUOTE>
Whether to put the sbin directories in ordinary users' paths is a matter
of debate. The debate goes like this:
</BLOCKQUOTE>
<BlockQuote>
<BLOCKQUOTE>
CON: The sbin directories are for administrative commands that ordinary
users would have no reason to use.
</BLOCKQuote>
<BLOCKQUOTE>
PRO: But what about traceroute, ping, route and ifconfig? Ordinary
users may want to run these to see if a host is down, find out which
ISPs it goes through to reach a host, find out what our IP number is
and which hosts are our gateways.
</BLOCKQUOTE>
<BLOCKQUOTE>
CON: I don't want my users running ping because it increases network
load and it can be misused for a DoS attack. As for route and ifconfig,
too bad.
</BLOCKQUOTE>
<BLOCKQUOTE>
PRO: You're a fascist. I'm putting them in my path myself. Nyaa,
nyaa, nyaa!
</BLOCKQUOTE>
</BlockQuote>
<BLOCKQUOTE>
Some programs are borderline so it can be difficult to determine whether
they belong in sbin or bin. Also, there are disagreements and
uncertainty about what sbin is really for. (I've heard it was
originally for statically-linked programs in case their dynamic
counterparts weren't running.)
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Actually, that was my submission....tongue and cheek.....not exactly
questions for the column! Whoops...should have been more specific!
</STRONG></P>
<P><STRONG>
Paul J. Bussiere
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
Submitted to the Mailbag and The Answer Gang. It'll be up to the
editor of those sections whether to publish it.
</BLOCKQUOTE>
<blockquote><font color="#000066"><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather] And, I decided to publish it both ways, but then I screwed up. Oh well,
I'm only human...
</font></blockquote>
<!-- end 12 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<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"
>Sometimes, we just don't know what to say</H3>
<p><strong>From darrell rolstone
</strong></p>
<p align="right"><strong>Answered By Ben Okopnik, Dan Wilder, Heather Stern
<br></strong></p>
<!-- ::
Sometimes, we just don't know what to say
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
:: -->
<p><strong>
Dear Tag staff , especially Ben,
</strong></p>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Well folks....I've patiently waited several weeks for a response to my
LONG letter.....and have given up and am re-contacting you to ask if you
even got it?
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Dan]
Your message of 2 May 2001 did indeed arrive. It may be found
at the list archive,
</BLOCKQUOTE>
<BLOCKQUOTE>
<A HREF="http://www.ssc.com/mailing-lists/tag/200105/0020.html"
>http://www.ssc.com/mailing-lists/tag/200105/0020.html</A>
</BLOCKQUOTE>
<BLOCKQUOTE>
You raise some interesting questions.
</BLOCKQUOTE>
<BLOCKQUOTE>
The fact that the Open source software base comprises untold millions
of lines of code (has anybody ever counted?) indicates that there must
be some reason people do this. Eric Raymond has a few interesting
ideas. See <A HREF="http://www.tuxedo.org/~esr/writings"
>http://www.tuxedo.org/~esr/writings</A>.
</BLOCKQUOTE>
<BLOCKQUOTE>
I suspect that absence of responses on this mailing list was due to
the fact that none of the regular posters felt they had much in
particular to contribute, at least on the day your mail appeared,
to the questions you raise. For this I don't really apologise;
we're all volunteers here, and we do what we can.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Ben's first response was IMMEDIATE and so ...
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
I guess I should stop responding so IMMEDIATELY... &lt;wicked grin&gt;
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
...and so you have sadly developed the illusion that you should get 1 hour
turnaround on your problems from TAG. That's not the way it works here.
<EM>Linux Gazette</EM> is not any sort of company, TAG's just a batch of friends
that try to help folks like you out... and the Gazette gets to publish
the results, if it looks like they'd "Make Linux a Little More Fun!" for
others. That's the only pay we get, too. You want timely, buy a tech
support contract from some Linux vendor that sells them.
</BLOCKQUOTE>
<BLOCKQUOTE>
I remind you that The Answer Gang does not guarantee any answers will ever
arrive, much less in a timely fashion.
</BLOCKQUOTE>
<BLOCKQUOTE>
Even if it were a company a fast turnaround might be unreasonable, but that
depends on whatever the original problem was. Most companies actively limit
what type of questions they'll even bother to answer; "Linux" is quite a
broad topic, these days.
</BLOCKQUOTE>
<BLOCKQUOTE>
If Ben or any of the other members of the Gang continue the thread, great.
If not, oh well. Sorry you got your hopes up. You can re-send your message
if you like. If you do, its successful delivery to any TAG gurus doesn't
obligate them to answer.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
... I'm thinking maybe something went
wrong in the sending process, although I never received a "failure" notice!
It has also suspiciously disappeared from my "sent messages" folder!!!
I have to wonder if you guys are being "watched"? Immediately after
mailing you, I received some strange e-mails .....one from
"<em>friends@hoovertime</em>" with no message.....just an attachment!
</strong></p>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
So, it looks like your site gets spam too. (Due to an open policy of
receiving queries from Linux users all over the world, we get an unfair
share, ourselves.) Luckily, you probably can do something about it...
procmail filters or something. There have been a few useful articles
against that subject in recent issues of <em>LG</em>.
<br> (To be fair, it might be little hard to filter spam in your hotmail
account. Oh well. )
</blockquote>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Anyway, please let me know if infact you did receive my e-mail of
several weeks ago.
</STRONG></P>
<P><STRONG>
Thanks
</STRONG></P>
<P><STRONG>
Darrell Rolstone / Vector Synergy Intl
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
We get an increasing amount of mail each month. You have provided no special
context that I could use to find it anyways other than your name. It's not
reasonable for us to go looking for it. I hope that some of what Ben said for
you was helpful so far. If your actual thread of question and answers is
useful to others by the end of the month, it may get published in whole or part.
</BLOCKQUOTE>
<BLOCKQUOTE>
Yes, I agree, it's polite to continue a thread in progress, and for all I
know, 3 of them have it lazing about in their draft folders. One of TAG may
have sent you something which never arrived at your end. If they didn't copy
the publishing staff here, I actually have <EM>no means</EM> to find it for you, or
even to publish it later.
</BLOCKQUOTE>
<BLOCKQUOTE>
Meanwhile, good luck in your endeavors.
</BLOCKQUOTE>
<!-- . . . . . . . . . . . . . . . . . . . -->
<HR WIDTH="40%" ALIGN="center">
<p><strong>
<img src="../gx/dennis/bbubble.gif"
height="50" width="60" alt="(?) " border="0"
>
Dear Dan, ( and stern Heather too!)
</strong></p>
<p><strong>
Thanks SO MUCH for answering! Now I know that my letter did infact
arrive! I REALLY appreciate it and all that you and the other volunteers do.
I hope that my "interesting questions" generate some "food for thought"
among linux programmers! It looks like IBM and their new associates will be
addressing many of the drawbacks that I pointed out ....by paying their
programmers to code using the linux kernal (along with the NSA)! I hope that
"far-reaching" programs like the two I have initiated will garner monetary
support somehow!
</strong></p>
<p><strong>
Please know that I put myself "at your service" to the whole of the
linux community, as a "synergy design consultant" ( which pretty much covers
EVERYTHING) and would be glad to volunteer to contribute my prospective on
any projects/problems!
</strong></p>
<p><strong>
Remember: "the significant problems we face today cannot be solved by
the same level of thinking that created them" Albert Einstein.
</strong></p>
<p><strong>
May the Source be with you, Darrell Ernest Rolstone
</strong></p>
<!-- 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"
>Bulk File Transfers from Windows to ???</H3>
<p><strong>From Brian Schramm on the L.U.S.T List
</strong></p>
<p align="right"><strong>Answered By Jim Dennis
</strong></p>
<!-- ::
Bulk File Transfers from Windows to ???
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
:: -->
<P><STRONG>
I have a Linux machine on a cable modem. That server has a lot of files
that I need to get to from a Windows machine in another location that is
on a dsl line. I have tried samba but it is aparently blocked at the
cable co. I think NFS is open but there is no nfs client that I have
gotten to work on windows yet I have pcnfs installed on my
<A HREF="http://www.debian.org/">Debian</A> server
and my local 95 machine does not attach to it. I have tried ice-nfs and
omni for client software.
</STRONG></P>
<P><STRONG>
Is there a way to do this? Is there a problem in doing this? I am at my
wits end.
</STRONG></P>
<P><STRONG>
Please help.
</STRONG></P>
<P><STRONG>
Brian Schramm
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [JimD]
The approaches you've attempted so far all related to file sharing
protocols (NFS, SMB). These are normally only used on the LAN or over
VPN or dedicated links. In general you're best approach for a one-time
or any periodic file transfers is to archive the files into one large
file (a tar file for UNIX and UNIX-like systems, a ZIP file for MS-Windows
and MS-DOS systems, a Stuffit or similar file for MacOS boxes). Usually
you'd compress the archive as well (gzip or bzip2 for UNIX/Linux, implicit
for .zip and .sit files).
</BLOCKQUOTE>
<BLOCKQUOTE>
Once you have the files archived you can use ftp, scp (SSH copy) or
even rsync over ssh to transfer it to the remote system.
</BLOCKQUOTE>
<BLOCKQUOTE>
Of course this might take a very large amount of temporary file space
(usually at least half of the total size of the originals) at each
end of the connection. If this is a limiting consideration
for your purposes, perhaps burning CDs of the data and shipping them
via snail mail might be the bettern approach.
</BLOCKQUOTE>
<BLOCKQUOTE>
Under UNIX you can avoid the large temporary copy/archive requirements
at both ends by archiving into a pipeline (feeding the archive data
into a process which transmits the data stream to the remote system)
and by having the remote system extract the archive on-the-fly.
</BLOCKQUOTE>
<BLOCKQUOTE>
This usually would look something like:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQuote><code>
cd $SOURCE &amp;&amp; tar czvf - $FILE_DIR_LIST | ssh <A HREF="mailto:someone@somehost"
>someone@somehost</A> '(cd $DESTINATION &amp;&amp; tar xzpf - )'
</code></BLOCKQuote></BLOCKQUOTE>
<BLOCKQUOTE>
or possibly like:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQUOTE><CODE>
ssh <A HREF="mailto:someone@somehost"
>someone@somehost</A> '(cd $SOURCE &amp;&amp; tar czvf - $FILE_DIR_LIST )' | cd $DESTINATION &amp;&amp; tar xzpf -
</CODE></BLOCKQUOTE></BLOCKQUOTE>
<BLOCKQUOTE>
... depending on whether you want to push the files from the local
machine to a remote, or vice versa
</BLOCKQUOTE>
<BLOCKQUOTE>
For MS-Windows and MS-DOS systems, I have frequently used a Linux boot
floppy (like Tom's Root/Boot at: <A HREF="http://www.toms.net/rb"
>http://www.toms.net/rb</A>) or a bootable
CD (like <A HREF="http://www.linuxcare.com/">Linuxcare</A>'s Bootable Business Card --- at:
<A HREF="http://open-projects.linuxcare.com/BBC/index.epl"
>http://open-projects.linuxcare.com/BBC/index.epl</A>). Basically you boot
them up, mount up their FAT or VFAT filesystems and do your thing --
in those cases I've usually had to use netcat in lieu of a proper
ssh tunnel; but that's just laziness.
</BLOCKQUOTE>
<BLOCKQUOTE>
Here's a sample script I use to receive a system backup from
a Windows '98 Point of Sale system (which I call "pos1" in by
backup file.
</BLOCKQUOTE>
<blockquote><pre>#!/bin/sh
ifconfig eth0 172.17.17.1 netmask 255.255.255.0 broadcast 172.17.17.255
nc -v -v -n -w 6000 -p 964 -l 172.17.17.2 964 -q 0 | bzip2 -c &gt; $( date +%Y-%m-%d )-pos1.tar.bz2
## cp /etc/resolv.conf.not /etc/resolv.conf
sync
</pre></blockquote>
<BLOCKQUOTE>
I run this on one system, and then I go to the other system,
boot it, configure the network to the ...2 address; as referenced
in my nc command above, mount my local filesystems (the C: and D: drives
under MS-DOS; create a mbr.bin file using dd if=/dev/hda of=/mnt/mbr.bin
count=1 bs=512) and feed the receiver with:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQUOTE><CODE>
tar cBf - . | nc -p 964 172.17.17.1
</CODE></BLOCKQUOTE></BLOCKQUOTE>
<BLOCKQUOTE>
(nc is the netcat command).
</BLOCKQUOTE>
<BLOCKQUOTE>
If I had to manage any Win2K or NT systems I'd probably just install
the Cygwin32 tool suite and see if I could use these same tools
(tar, nc, ssh, etc) natively). Obviously MacOS X should probably
have these tools already ported to it; so similar techniques should
work across the board.
</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"
>Cannot Login Question</H3>
<p><strong>From Nancy Laemlein
</strong></p>
<p align="right"><strong>Answered By Ben Okopnik
<br></strong></p>
<!-- sig -->
<P><STRONG>
Hello,
</STRONG></P>
<P><STRONG>
I found my problem listed as
<A HREF="../issue37/tag/46.html"
>http://www.linuxgazette.com/issue37/tag/46.html</A>, but no solution.
</STRONG></P>
<P><STRONG>
I have been running RH6.2 kernel2.2.14-50 on I586, as two test servers.
</STRONG></P>
<P><STRONG>
Both have been running for one-two months. One morning I restarted both
servers and then I encountered no normal user could successfully login. I
could only login as root, or even more bizarre, as any user but using the
root password.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Hm. I hate to jump to such an obvious conclusion, but that kind of
behavior seems "man-made" rather than some specific failure. Your site
may well have been cracked.
</BLOCKQUOTE>
<BLOCKQUOTE>
One of the first things I'd do - given the problems that you're
encountering - is compare the size of your "<TT>/bin/login</TT>" and "<TT>/bin/bash</TT>"
to those on a normal system (this assumes the same distro or at least
GNU utility versions on the machines.) If they're significantly larger,
they're probably "rootkit" versions, compiled with the library calls in
the executable. If you can compare the sizes with the originals (i.e.,
look inside the RPMs), so much the better.
</BLOCKQUOTE>
<BLOCKQUOTE>
Check your access logs. The intruder can wipe those, but there's always
a chance - most script kiddies are pretty inept.
</BLOCKQUOTE>
<BLOCKQUOTE>
Do a "find <TT>/</TT> -name bash" to search for an extra copy (usually SUID'd)
of "bash"; in fact, doing an occasional search for SUID'd files on your
system - and being familiar with that hopefully very short list - is a
good thing to do on any system you admin.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
><ul>
<LI>The servers do not boot to Xwindows(gdm)
<LI>No error at bootup
<LI>manage a login for user/root password
<LI>"startx" produces -
<code>
"Authentication failed - cannot start X server.
<br> Perhaps you do not have console ownership?"
</code>
<br>No user can load startx
Only root can load startx - not good
<LI>upon shutdown error message results:
<code>
"Sending all processes the TERM signal ...
<br> rpc.statd forgot to set AF_INET in udp sendmsg.
<br> Fix it!"
</code>
</ul></Strong></p>
<P><STRONG>
I have created a new user and tried loggin in; same scenario, new user
cannot login with newly assgined user/password, can login as new user
using root password.
</STRONG></P>
<P><STRONG>
For "startx" problem I have checked <TT>/etc/security/console.perms</TT> and edited
File classes
</STRONG></P>
<pre><strong> from:
&lt;console&gt;tty=3D[0-9][0-9]* :[0-9]\.[0-9] :[0-9]
to:
&lt;console&gt;tty=3D[0-9][0-9]* vc\/[0-9][0-9]* :[0-9]\.[0-9] :[0-9]
</strong></pre>
<P><STRONG>
I think the origin is in the password problem but I don't know where to
start. Servers are using shadow password, files <TT>/etc/passwd</TT> and
<TT>/etc/shadow</TT> look like this:
</STRONG></P>
<pre><strong> -rw-r--r-- 1 root root 944 passwd
-rw-r--r-- 1 root root 944 passwd-
-r-------- 1 root root 979 shadow
-r-------- 1 root root 979 shadow-
</strong></pre>
<P><STRONG>
Do you have any ideas?
</STRONG></P>
<P><STRONG>
Many Thanks -
<br>Nancy Laemlein
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
The perms look OK; that might not have much to do with it though. If
you find that you have indeed been cracked, you'll need to reinstall
your system (since <em>anything</em> could be compromised), and read the
Security-HOWTO before putting it back on-line. Running Bastille (a sort
of an automated security audit) on your machine is a fairly good idea.
</BLOCKQUOTE>
<BLOCKQUOTE>
Do note that the problem could be as simple as some strange library
succumbing to bit rot. Doing diagnostics via e-mail with limited
information is a middlin' tough job.
</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"
>LG 24 - Tips: Yet another way to find</H3>
<p><strong>From Bill Thompson
</strong></p>
<p align="right"><strong>Answered By Ben Okopnik
<br></strong></p>
<!-- sig -->
<P><STRONG>
Hi,
</STRONG></P>
<P><STRONG>
I have been using grepfind since it was published in the LG 24 Tips
column with great results. Since using Mandrake 8.0, it no longer
works as before. It does it search but nothing is written to the
display. The command-line returns as many lines down as the results
of grepfind found. A friend using Mandrake 7.2 says grepfind works.
Another friend using Mandrake 8.0 reported the same results as I get.
</STRONG></P>
<P><STRONG>
PLEASE help!
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Bill, the only thing I can figure is that the syntax of 'find', 'sed',
or 'grep' has been changed in the 8.0 distro. Nowadays, there are
better ways to do what you want - as an example, my version of 'grep'
(GNU 2.4.2) supports recursive searching via the "-r" switch - but if
you want to find out what's bugging your script, try removing the
"layers" one at a time.
</BLOCKQUOTE>
<BLOCKQUOTE>
As an example, in 'grepfind' you have the following lines:
</BLOCKQUOTE>
<blockquote><code><font color="#000033"><br>if [ "$2" = "" ]; then
<br>find . -type f -exec egrep -i "$1" /dev/null {} \; | sed -e 's/[^ -~][^-~]*/ /g'
</font></code></blockquote>
<BLOCKQUOTE>
(This is the "single-argument" mode, so that's how you'd test it.) Try
eliminating the "sed" part:
</BLOCKQUOTE>
<blockquote><code><font color="#000033"><br>if [ "$2" = "" ]; then
<br>find . -type f -exec egrep -i "$1" /dev/null {} \;
<br># | sed -e 's/[^ -~][^-~]*/ /g'
</font></code></blockquote>
<BLOCKQUOTE>
Now run the script and see if you get reasonable output; if you do, the
problem is in 'sed'. If you don't, the problem is in 'find' or 'egrep';
split them out like so:
</BLOCKQUOTE>
<blockquote><code><font color="#000033"><br>if [ "$2" = "" ]; then
<br>find . -type f
<br># -exec egrep -i "$1" /dev/null {} \;
<br># | sed -e 's/[^ -~][^-~]*/ /g'
</font></code></blockquote>
<BLOCKQUOTE>
This time, if the problem disappears, it's in 'egrep'; if it still
doesn't, it's in 'find'. Check the appropriate manpage for whatever the
syntax change may be; someone may have decided to go back to that
perverted version of 'find' that requires "-print" in order to output
anything (yechhh!), for example. After that, the only thing that's left
is figuring out what the author wanted the function to do, and
replacing the syntax with the new version that will do the same thing.
</BLOCKQUOTE>
<BLOCKQUOTE>
Good luck.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Ben,
</STRONG></P>
<P><STRONG>
Thanks for the troubleshooting tip. 'sed' was the offender. I recompiled
the original one from Mandrake 7.2 and now all's well. To date, I haven't
experienced any fallout when 'sed' is used elsewhere.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
It's interesting to note what subtle bugs can come up even in shell
scripts over time (this, of course, was not a script bug but a GNU
util, but still...) Glad that I was able to help, Bill.
</BLOCKQUOTE>
<!-- end 6 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<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"
>Dash it All! Coping with ---Unruly--- Filenames</H3>
<p><strong>From John Murray
</strong></p>
<p align="right"><strong>Answered By Jim Dennis, Andrew Higgs, Ben Okopnik
<br></strong></p>
<P><STRONG>
I was experimenting with the TAR command and trying to get it to "exclude"
some files. I finally got it to work but in one of my tests I ended up
sending the output of the TAR command to a file called -exclude. I want to
delete -exclude, but when I type in the command to delete it "rm -f
-exclude", the command thinks the file name is an option. The same thing
happens when I try to rename the file. Any ideas??
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [JimD]
This is a classic UNIX FAQ. I pose variations of it to prospective
sysadmins and support personnel when I interview them.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Andrew]
Hi John
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQUOTE><CODE>
Try 'rm -f -- -exclude'. The '--' terminates the options list.
</CODE></BLOCKQUOTE></BLOCKQUOTE>
<BLOCKQUOTE>
Kind regards
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [JimD]
<TT>./</TT> is more portable (works with <EM>all</EM> UNIX commands on <EM>all</EM> versions
of UNIX) and is even shorter (saves one space).
</BLOCKQUOTE>
<BLOCKQUOTE>
The current directory in UNIX (and Linux, of course) is always
the "dot" directory. When we use a filename with <EM>no</EM> slashes
(directory/subdirectory delimiters) in it; that's merely a shorthand
for "the one in the current directory." So any file foo is also
./foo.
</BLOCKQUOTE>
<BLOCKQUOTE>
More importantly -foo is the same as <TT>./-foo</TT> (Of course it's also
the same as $(pwd)/-foo --- the full path to the filename).
</BLOCKQUOTE>
<BLOCKQUOTE>
NOTE: I give half credit for people who suggest " -- " (a double dash
argument to the rm or some other commands; signifying the end of all
options processing by that command and thus forcing all following
arguments to be taking literally rather than as possible option switches).
</BLOCKQUOTE>
<BlockQuote>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
&lt;laugh&gt; How about for using Midnight Commander? Scroll down to the
filename, hit 'F8'. Gone.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [JimD]
Half credit. What if mc isn't on this box? How about
mc's "undelete" feature? Is that file <EM>really</EM> gone?
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Erm... the "undelete" feature is a facet of the ext2 file system;
nothing to do with MC itself, which just provides an interface to it.
&lt;grin&gt; You'd get a _debit_ for that one.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [JimD]
I'll take the hit --- but I'll stick by my guns on the opinion that
"rm is forever" (even though I've recovered deleted files using
grep, dd and vi). I've read about mc's undelfs before, but I've
never used it and I didn't remember the details.
</BLOCKQUOTE>
<blockquote>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
"undelfs", despite the confusing name, is no more a filesystem than is
their "tarfs": 'foo'fs, in MC parlance, is simply a way of looking at
'foo', where 'foo' is presented as a filesystem - sort of like what
the 'mount' command does with a DOS floppy. In the case of "tarfs",
it allows you to look at tar files as if they were directories and
subdirectories containing files; with "undelfs", it allows you to look
at the deleted-but-not-yet-reused filespace in ext2 as if it was a
directory. Pretty neat gadget that greatly facilitates the undeletion
process; however, the initial read (it would have to scan the entire
partition, obviously) takes a while. MC, despite its ease of use, goes
<EM>very</EM> deep; you can actually edit the various 'fs' files, and even
create your own!
</BLOCKQUOTE>
</blockquote>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [JimD]
I'll give 3/4 credit for anyone who says: "I just use
(x)emacs dired-mode for all my file management, so I'd
just C-s (search) to move point to it, and hit the 'd'
key."
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Hey! What if emacs isn't on the box? In my opinion, that's a higher
probability than with MC.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [JimD]
I'll even give 90% credit for someone who says: "I
forgot all my shell tricks since I do everything in
perl. So I'd just use: perl -e 'unlink("-foo");' and
be done with it"
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
&lt;laugh&gt; That's what I used the last time I had to rename a bunch of MP3s
(KOI8-R (Russian) song names on my 'LANG=C' system). Even MC had a
problem; Perl chewed it right up. Except in my case, the above would be
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQUOTE><CODE>
perl -we'unlink -foo'
</CODE></BLOCKQUOTE></BLOCKQUOTE>
<BLOCKQUOTE>
It's not a list and there's no precedence issue (no parens), and there's
no interpretation necessary (no double-quotes). Also, enable warnings to
tell you if something weird happens.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [JimD]
I give extra credit for those who recognize it as an FAQ
and laugh at me for posing the question.
</BLOCKQUOTE>
<BLOCKQUOTE>
I'll give double credit to anyone that recites the FAQ,
and ticks off six different ways to do it (--, <TT>./</TT>, mc, perl,
dired, and one I've never heard of) and tells me that he saw
the whole thread on TAG!
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
Edit the inode directly - hexedit, MC, etc.
Use C's "int unlink (const char *FILENAME)".
Tell an assembler programmer that you've found something that can't be
done in it. &lt;evil grin&gt;
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [JimD]
That would be using fsdb or debugfs and use clri and unlink
commands therein.
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
(and, from the "incidental feature" side of the fence...)
</BLOCKQUOTE>
<BLOCKQUOTE>
Use a large electromagnet.
Take a hammer to the hard drive.
Take off and nuke the site from orbit (it's the only way to be sure.)
</BLOCKQUOTE>
<BLOCKQUOTE>
And, as the bonus option, go to Jim Dennis and say, "Jim, I have this
beautiful barometer I'll give you if you..." Oh, oops. Wrong story.
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</BLOCKQUOTE>
<BLOCKQUOTE>
...Oh. You said "_one_ [way] I've never heard of"?
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Now, don't you wish I was a hiring manager at someplace
you wanted to work?
</BLOCKQUOTE>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Ben]
If I wanted to be a sysadmin (which I don't), definitely. Knowing that
the people around me are vetted by someone knowledgeable instead of
some HR bozo with a checklist &lt;barely managing to supress Major Rant
with a sack&gt; would be a Good Thing!
</BLOCKQUOTE>
</BlockQuote>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [JimD]
I give zilch credit for any efforts to use quotes, backslashes, or
other shell "escaping" techniques.
</BLOCKQUOTE>
<BLOCKQUOTE>
The leading dash is conventionally used by UNIX commands (and specified
in the POSIX standards for many of them) as a way to distinguish
"object" arguments (things the command will work on) from "options"
(or adverbial) arguments (also known as "switches") (which specify
<EM>how</EM> the command will work). Note that this is a convention; and that
it applies to commands. The shell (command interpreter) does no
special parsing of leading dashes. Quoting and escapingn only affect
how the shell parses the command line (how it is passed to the commands)
--- so no amount of shell shenanigans will ever overcome a "dashed"
filename problem.
</BLOCKQUOTE>
<BLOCKQUOTE>
(BTW: That's the easiest question on my list of "qualifiers" for
sysadmins. No offense intended, but I need people to know the
FAQs before I can let them loose with a root prompt on my production
systems)
</BLOCKQUOTE>
<blockquote>
<BLOCKQUOTE>
Here's a slightly tougher one: "due to some merger we need to
migrate a set of users to a block of (formerly unused) UIDs;
why and how? Also what are some 'gotchyas' in this process?"
(Preferred answer to "how" is in the form of shell script
pseudocode; feel free to gloss over details with comments on
how you'd safely figure out implementation specifics).
</BLOCKQUOTE>
<BLOCKQUOTE>
That's a medium level qualifier.
</BLOCKQUOTE>
<BLOCKQUOTE>
BTW changing chowning all of the files belonging to just <EM>one</EM>
user is a one-liner; However, it's not as simple as you'd think.
Try that for 3/4 credit.
</BLOCKQUOTE>
<BLOCKQUOTE>
Answer next month; if you remind me! (My rough cut at this
is just over 20 lines long).
</BLOCKQUOTE>
</blockquote>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [JimD]
The UNIX FAQ is at:
</BLOCKQUOTE>
<BLOCKQUOTE><BLOCKQuote>
<A HREF="http://www.faqs.org/faqs/unix-faq/faq/contents"
>http://www.faqs.org/faqs/unix-faq/faq/contents</A>
</BLOCKQuote></BLOCKQUOTE>
<BLOCKQUOTE>
... and this is question 2.1
</BLOCKQUOTE>
<BLOCKQUOTE>
Read that before you su again!
</BLOCKQUOTE>
<!-- 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"
>File Tranfers with AIM (AOL Instant Messenger)</H3>
<p><strong>From Steve Paugh
</strong></p>
<p align="right"><strong>Answered By Jim Dennis
<br></strong></p>
<P><STRONG>
I have a working LRP (linux router project www.linuxrouter.org) box
and I would like to make file transfers with AOl Instant Messanger
possible from behind this box to the outside world for my Windows
clients. I am not sure excately how to do this
</STRONG></P>
<P><STRONG>
I've seen something like the below in a different setup that hadn't
been tested.
</STRONG></P>
<P><STRONG>
My understanding is that the 0.0.0.0/0 is for dhcp. but i am not
sure about the $AIM_HOST
</STRONG></P>
<P><STRONG>
Does anyone have any idea on a rule that would allow what I need? I
am kinda new to firewalling and would appreicate any help you can
give me.
</STRONG></P>
<pre><strong>$IPCHAINS -A input -s 0.0.0.0/0 -d $IP_EXT/32 5190 -p tcp -j ACCEPT
if [ "$AIM_HOST" != "firewall" ]; then
$IPMASQADM portfw -a -P tcp -L $IP_EXT 5190 -R $AIM_HOST 5190
fi
</strong></pre>
<P><STRONG>
Much thanks,
<br>Steve Paugh
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [JimD]
First, I know NOTHING about AIM. I figured out that it is AOL's
interactive chat system over the Internet; but I don't use it or
anything like it (though it, ICQ and so many other "instant messaging"
systems are available). I prefer e-mail and I already spend WAY too
much time interacting with people via that channel.
</BLOCKQUOTE>
<BLOCKQUOTE>
The only "instant messaging" I do for now is "voice over POTS line"
(or via cell phone). I don't even know how to send SMS messages to
my phone. (It seems to be a fully WAP capable toy --- but that's another
gadget that I haven't invested the time to learn).
</BLOCKQUOTE>
<BLOCKQUOTE>
O.K. Now that I've set your expectations properly, you are getting this
response from a backwoods, curmudgeonly geezer, I'll answer your question.
</BLOCKQUOTE>
<BLOCKQUOTE>
In the context of this script fragment 0.0.0.0/0 is an argument to a
command. Specifically the script is calling on some command whose
name we can't see because it is stored in a variable named IPCHAINS.
The shell (the script interpreter) "dereferences" $IPCHAINS as the
script is run. The $ is a "dereferencing operator" -- it means:
replace this variable with the variable's current value. All of the
$XXXX thingies in this fragment are shell variables.
</BLOCKQUOTE>
<BLOCKQUOTE>
As you can see shell programmers usually capitalize the names of
their variables, so they standout and are easier to spot. This is
merely a convention. In this case the $IPCHAINS and $IPMASQADM
variables clearly supposed to be holding the full path to the
ipchains and ipmasqadm utilities. In some other part of this
script (not shown) or in some parent process that invoked this
script, there would be some assigment to these variables that
provided the values for a given system. This allows the programmer
to localize the system specific code to some point near the top
of the script so that they can make any necessary changes in a
single place rather than having to hunt throughout the whole script.
</BLOCKQUOTE>
<BLOCKQUOTE>
As an argument to the ipchains command, the -s refers to a
purported source address <EM>pattern</EM>. In that case 0.0.0.0/0 refers to
<EM>any</EM> IP address. The -d refers to a destination address pattern,
$IP_EXT is a variable (which presumably would be set to the IP
address of our router's external interface, as the name clearly
implies). The <TT>/32</TT> indicates that this is a full 32-bit IP address,
that it is NOT a subnet designator; successively smaller values would
indicate progressively larger networks and subnets based at certain
special addresses (space doesn't permit a full descripting of subnetting
and routing; but search the LG archives for a 20 page treatise on that
topic). The 5190 is a port number; and the -p refers to the
protocol, which in this case, is TCP (as opposed to UDP, ICMP, etc).
So this ipchains rule applies to packets which purport to be from
anywhere, and are destined for TCP port 5190 on the local systems
external interface.
</BLOCKQUOTE>
<BLOCKQUOTE>
The -j in ipchains is a bit confusing. In the man pages and docs
it refers to "jump" (while processing the sets of rules, if any
packet matches all of these conditions, "jump" to another set
of rules to process that set of rules). However, in this case
we aren't "jumping" to a different chain of rules; we're "just"
accepting the packet into the system. When I teach people about
the IP Chains package I teach this concept. -j either means "just"
and in "just ACCEPT, DENY, REJECT, REDIRECT, MASQ, or RETURN"
the packet <EM>or</EM> it means "jump" to a user defined (and named)
chain of rules.
</BLOCKQUOTE>
<BLOCKQUOTE>
In our example the -A means to "add" a rule, and the "input"
argument is naming the chain of rules to which the rule will be
added. The input chain is one of the pre-defined sets of rules
that the Linux 2.2.x kernel always has present (if it has the
ipchains support compiled it at all).
</BLOCKQUOTE>
<BLOCKQUOTE>
Oh yeah! I didn't put any of this into context yet. The
Linux kernel has optional builtin support for packet filtering
and masquerading. This has undergone numerous changes over the
years, starting with the ipfw code in 1.3.x, the ipfwadm code in
2.0.x, and through the ipchains code in 2.2.x and the new net filter
code (usingn iptables) in 2.4
</BLOCKQUOTE>
<BLOCKQUOTE>
In all of these cases the kernel has a table of rules against which
it checks every packet that it receives, and/or every one which it
attempts to send, and/or any packet it intends to forward. (I kept
saying "and/or" because the exact rules of which rules sets are
traversed differ from one major kernel release to another --- so
one packet that may have to traverse the incoming, forwarding, and
outgoing rulesets in one release and might only need to traverse <EM>one</EM>
of them in newer kernels; read the appropriate HOWTOs and look at the
ASCII art diagrams for further enlightenment on this issue if you
need it).
</BLOCKQUOTE>
<BLOCKQUOTE>
There are various commands: ipfwadm, ipchains, iptables which match
the major kernel releases and allow the administrator to insert or
add rules to these kernel tables, to delete or flush the rulesets,
to query the system and determine how many packets matched a given
rule, etc.
</BLOCKQUOTE>
<BLOCKQUOTE>
It's handy to understand this bit of background. The ipchains
command here is adding a rule to the kernel's input chain.
</BLOCKQUOTE>
<BLOCKQUOTE>
The next command line is a conditional; basically it's saying that
"if the AIM_HOST is not the firewall" then (it must be some other
system behind the firewall) so we should use the ipmasqadm command
to set up a port fowarding rule. We will "add" a rule for TCP
that will take any packets to our "local" port 5190 on our external
interface, and we'll forward it to port 5190 on a remote host, whose
name or address is stored in $AIM_HOST.
</BLOCKQUOTE>
<BLOCKQUOTE>
Personally I think this is sloppy coding. What if I wanted to
name my internal AIM_HOST "firewall?" Using a plain word like
"firewall" as a sentinel value is kind of bogus. Using localhost
(the canonical name for the local system) would be quite reasonable.
However, it's a nitpick.
</BLOCKQUOTE>
<BLOCKQUOTE>
The last line is simply the Bourne shell way of marking the end of
an "if ... then ... else" block. It's the word "if" spelled backwards.
If we were looking at the more complex conditional structure called
a "case" then we'd find the end of that block by looking for the
"esac" token. Once upon a time I read about some other programming
language which was Stephen Bourne's inspiration for using this quirky
syntax. Thankfully he only did this with conditionals, and we don't
have to end our "while" loops with "elihw" and our "for" loops with
"rof" --- even better we don't have to try ending our "do" loops
with an octal dump.
</BLOCKQUOTE>
<BLOCKQUOTE>
[Sorry! Inside joke there. The UNIX od command is an "octal dump"
utility, so "do" backwards would create an inconvenient token collision].
</BLOCKQUOTE>
<BLOCKQUOTE>
Actually the while, until, and for loops (and the odd select prompting
construct) all use the "do" and "done" tokens to delimit them.
</BLOCKQUOTE>
<BLOCKQUOTE>
So, back to your original question: It would appear that you can
get AOL Instant Messenger to work through your firewall simply by
relaying traffic for TCP port 5190 to the appropriate system. This
fragment of shell code gives a rough example of how to do that on a
Linux 2.2.x system (or later, but using the ipchains support module).
However, you'll have to fill in the variables as appropriate to your
system. You can just replace all the $VARIABLE_NAME thingies in this
example with the literal text that points to your copy of ipchains,
your copy of the ipmasqadm command, your external IP address, and
(possibly) the IP address of the internal system where you'd be running
your IM client.
</BLOCKQUOTE>
<!-- sig -->
<!-- end 8 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/9"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 9 -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>reverse dns</H3>
<p><strong>From Iskandar Awall
</strong></p>
<p align="right"><strong>Answered By Mike Orr
<br></strong></p>
<P><STRONG>
Do you know a step by step guide in doing reverse dns lookup in unix. I
have done a reverse dns lookup but it doesn't seem to be able to resolve.
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
You've got a choice of several commands. 'dig' seems to provide the
most information.
</BLOCKQUOTE>
<blockquote><pre>$ host 1.2.3.4
$ host domain.com
$ dig 1.2.3.4
$ dig domain.com
$ dig 1.2.3.4 ANY
$ dig domain.com ANY
$ nslookup
&gt; set type=any
&gt; 1.2.3.4
&gt; domain.com
&gt; [ctrl-d]
$
</pre></blockquote>
<BLOCKQUOTE>
If a reverse lookup fails, it probably means there is no reverse record
for that IP. There's no technical connection between forward and
reverse records. Indeed, they may even be maintained by different
organizations, so keeping them in sync may be impossible. The forward
record (name -&gt; number) is maintained by whoever hosts your domain
name--your ISP, another company, or you on your own server. The reverse
record (number -&gt; name) is maintained by whoever maintains your IP
number; i.e., your ISP. My ISP, For instance, refuses to change my
reverse record from a long ugly DSL name because they say their billing
system depends on that name. I have my own domain which I host myself
(to avoid the $5-$20/month the ISP would charge, which is an outrageous
rip-off for one minute's worth of labor when it changes, and no cost in
months it doesn't change--except the cost to run their DNS server, which
they'd have to do anyway), but since I cannot get the reverse record
changed, the forward and reverse records don't match. There are also
some ISPs out there who don't have reverse records at all, because they
think that setting reverse records for their customers' IPs is not worth
the time.
</BLOCKQUOTE>
<BLOCKQUOTE>
Users are caught in the middle of a debate over whether reverse records
should be used for identification. The pro argument is that it helps
identify spammers and abusers. The con argument (which I believe) is
that the purpose of domain names is convenience: so you don't have to
remember a number, and so that a site can maintain a "permanent"
identifier even if they move to another server or a different ISP.
You shouldn't <EM>have</EM> to have a domain name, much less have it set to
any particular value. And to identify scRipT kIddyZ, just do a simple
traceroute. The second-last hop is their ISP (or part of their own
network), and ISPs always have their own domain name showing. And
what if a computer has several domain names, each hosted at a different
organization? There can be only one reverse record, so all the other
names will be left out in the cold.
</BLOCKQUOTE>
<!-- sig -->
<!-- sig -->
<!-- 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"
>Closing Ports</H3>
<p><strong>From Saylormoon7
</strong></p>
<p align="right"><strong>Answered By Mike Orr
<br></strong></p>
<!-- sig -->
<P><STRONG><IMG SRC="../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Hello, I'm new to the 'puter world an I have been hearing a lot
about "closing ports." What exactly does this mean? And how would I go about
checking for open ports an closing them? Again like I said I am new to all of
this. So if you can help me, please explain it in the simplest way you can.
Thank you for you're time an help
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Mike]
A port is simply a positive integer the kernel uses to map a network
packet to the currently-running process (=application instance) it came
from or is going to. (This kind of port has nothing to do with the
physical ports on the back of your computer--serial, parallel, USB.) It
is not the Process ID (PID), because each process has only one PID but
it may have several network connections open simultaneously.
</BLOCKQUOTE>
<BLOCKQUOTE>
Your kernel has ports numbered from 1 to somewhere above 60000. Each
port is either open (currently in use) or closed (not in use). Most
ports are used as endpoints for current connections (every connection
has one local port on your computer and one remote port on the other
computer), but the ports you're interested in are the ones open in
"listening" mode. Listening means that there's no particular "other
end" of the connection--the server is waiting for a client to come along
and use it.
</BLOCKQUOTE>
<BLOCKQUOTE>
Think of prostitutes waiting on a street corner. The only difference
is that when a client <EM>does</EM> come up, the hooker (or rent boy) clones
herself (himself), and the clone walks off with the customer, while the
original continues waiting for the next customer.
</BLOCKQUOTE>
<BLOCKQUOTE>
Of course, programs have bugs, and a smart
cr@cKeR knows which versions
of which programs have exploitable vulnerabilities. So he'll go
scouring around the net looking for computers running vulnerable
services. Say you're running a version of Sendmail that has a certain
security weakness. The cracker finds it, and you're dead. But say you
don't need Sendmail running on that particular computer, so you turn it
off. The cracker comes along, gets a "Connection refused" error, and
curses the darkness. The port is closed, meaning there's no
application running to receive his request, so the kernel can do
nothing but say, "Sorry, nobody's home." Frustrated, the cracker goes and
bothers somebody else's computer instead.
</BLOCKQUOTE>
<BLOCKQUOTE>
Another trick some crackers do is to portscan the computer. This means
he'll try to connect to every possible port. Most will be rejected, but
at least he'll know which ones are listening. Then he can concentrate
his attack on those ports. Usually, he doesn't care about those
applications in themselves; he just wants to force the program into an
error condition such as a buffer overrun in such a way that it fools the
computer into giving him a root shell. Then he can try to crack the US
National Security Agency, and the guys in black suits will come knocking
at <EM>your</EM> door thinking it was you.
</BLOCKQUOTE>
<BLOCKQUOTE>
Closing ports is something you can do yourself: simply turn off all services you
don't have to have running on that machine. To combat portscanning,
you can use various software tools which log the attempt and/or raise
an alert. Some of these programs are described in the Linux Gazette
articles below. The articles also include other security tips for
keeping the bad guys out of your servers.
</BLOCKQUOTE>
<blockQuote><ul>
<LI><A HREF="../issue65/stumpel.html"
>http://www.linuxgazette.com/issue65/stumpel.html</A>
<LI><A HREF="../issue56/flechtner.html"
>http://www.linuxgazette.com/issue56/flechtner.html</A>
<LI><A HREF="../issue58/tag/7.html"
>http://www.linuxgazette.com/issue58/tag/7.html</A>
<LI><A HREF="../issue51/nielsen.html"
>http://www.linuxgazette.com/issue51/nielsen.html</A>
<LI><A HREF="../issue54/stoddard.html"
>http://www.linuxgazette.com/issue54/stoddard.html</A>
<LI><A HREF="../issue55/stoddard.html"
>http://www.linuxgazette.com/issue55/stoddard.html</A>
</ul></blockQuote>
<BLOCKQUOTE>
The last three articles are listed in chronological order and perhaps
give the best background.
</BLOCKQUOTE>
<BLOCKQUOTE>
You can also poke around <A HREF="http://www.securityportal.com"
>http://www.securityportal.com</A> for similar
security tips.
</BLOCKQUOTE>
<!-- end 10 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<A NAME="tag/11"><HR WIDTH="75%" ALIGN="center"></A>
<!-- begin 11 -->
<H3 align="left"><img src="../gx/dennis/bbubble.gif"
height="50" width="60" alt="(!) " border="0"
>Best of ISO burning under Windows.</H3>
<p align="right"><strong>Answers From
Robert L Keeney, G<>tz Waschk, Simon Rowe, Chris Olsen, Ed Wiget
</strong></p>
<p>We had a general request for burning CD images under Windows:
<a hrhef="../issue65/lg_mail65.html#wanted/1"
>http://www.linuxgazette.com/issue65/lg_mail65.html#wanted/1</a>
</p>
<p><strong>
I've downloaded the ISO file. Now what do I do
with it? I've burned a CD and it won't boot with it.
</strong></p>
<p>
We got a lot of answers
<IMG SRC="../../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
Here's the best ones:
</p>
<h4>MULTIPLE DIRECTIONS</h4>
<p>
Although most of these are Linux, there's a few Windows and at least one
Macintosh program shown.
</p>
<blockquote><img src="../gx/dennis/bbub.gif" height="28" width="50"
alt="(!)" border="0"> [Robert L Keeney]
The adaptec instructions worked for me. The others I haven't tried.
</blockquote>
<blockquote>
<a href="http://www.linuxiso.org/cdburninginfo.html"
>http://www.linuxiso.org/cdburninginfo.html</a>
</blockquote>
<h4>CDRECORD</h4>
<p>In the original our querent complained that the Howto instructed him
in cdrecord...</p>
<blockquote><img src="../gx/dennis/bbub.gif" height="28" width="50"
alt="(!)" border="0"> [G<>tz Waschk]
This program is portable and the windows version shares the parameters
with the linux version.
</blockquote>
<blockquote><dl><dt>
There is a binary for windows at:
<dd><a href="ftp://ftp.fokus.gmd.de/pub/unix/cdrecord/alpha/win32/"
>ftp://ftp.fokus.gmd.de/pub/unix/cdrecord/alpha/win32/</a>
</blockquote>
</blockquote>
First you have to find out the SCSI id of your CD recorder with
</blockquote>
<blockquote>
<code>
cdrecord -scanbus
</code>
</blockquote>
<blockquote>
...than you can burn the image with
</blockquote>
<blockquote>
<code>
cdrecord -device &lt;your_id&gt; filename.iso
</code>
</blockquote>
<h4>NERO BURNING</h4>
<p>A different reader noted that Nero Burning's FAQ on their website gives a
step by step example of burning a Redhat image to a disc.</p>
<blockquote><img src="../gx/dennis/bbub.gif" height="28" width="50"
alt="(!)" border="0">[Simon Rowe]
change the file extension to 'NRG' eg
<br>SuSE71.iso ---> SuSE71.nrg
</blockquote>
<blockquote>
The Nero software will then recognise the ISO image correctly, and should
burn it ok using the applications defaults (in version 5.x anyway!)
</blockquote>
<blockquote>
Once the filename extension has been changed, just double click the file in
Windows, and Nero should load ready to burn the ISO image. This works under
Windows 2000 and Windows 9x., I have not abused my computer with Windows ME
to try it there though
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</blockquote>
<h4>ADAPTEC EZ CD</h4>
<blockquote><img src="../gx/dennis/bbub.gif" height="28" width="50"
alt="(!)" border="0"> [Chris Olsen]
EZ-CD Creator will handle iso's really easily, just install it, and you can
right click the .iso image and select record to cd. Presto, a proper image,
not one big file on CD.
</blockquote>
<blockquote><img src="../gx/dennis/bbub.gif" height="28" width="50"
alt="(!)" border="0"> [Ed Wiget]
Windows 98 + Adaptec EZ CD Creator 4.xx
<ol>
<li> download the iso file for the distribution you wish to create cd's.
<li> assuming you already have Windows 98 on that machine and Adaptec EZ CD
Creator installed, you need to close everything down in the taskbar next to
the clock (no programs except systray and explorer should show up if you
press ctrl+alt+del).
<li> to make sure the large iso file is continuous, you should defragment
your hard drives. As an added measure, you should also clear your temp
folder of any files on C:\TEMP and C:\WINDOWS\TEMP
<blockquote>
I would hope this isn't actually necessary, it <em>should</em> be
making regular Windows filesystem calls to get at the bits, but
it might make it burn faster. My suspicion is that more of that
speed would be from a general Windows speedup, if it's been awhile
since your last defragmentation.
</blockquote>
<li> Open EZ CD Creator, and select Data CD
<li> From the File menu, select Create CD from CD Image (almost all cd
recording software for windows uses a similar statement to distringuish an
ISO file from normal data files)
<li> EZ CD Creator by default looks for a *.cif file, change this to iso from
the drop-down list in Files of Type.
<blockquote>
note: another reader commented that 4.02d defaults to extension
.cdi ... I suppose it would be nice if these Windows
burning programs would learn to agree on something. *sigh*
</blockquote>
<li> Browse to the location of the downloaded iso file and select it.
<li> Select Open
<li> The buttons Create CD, Track at Once, and Close CD should be selected.
<li> Select the speed of your CD-Recorder
<li> Select O.K.
<li> When it is finished recording the CD, place it in another computer and
make sure you can see the CD's contents.
</ol>
</blockquote>
<p>To which I will add, these may be mostly Linux binary programs on our
discs, but you should be able to mount up the disc and see their names,
at least. That's what all those "TRANS.TBL" files you might see are ...
support for long names on a CD filesystem.</p>
<p>Thanks to everybody who wrote in!
-- Heather</p>
<!-- end 11 -->
<center>
<H1><A NAME="tips"><IMG ALIGN=MIDDLE ALT="" SRC="../gx/twocent.jpg">
More 2&cent; Tips!</A></H1> <BR>
<!-- BEGIN tips -->
Send Linux Tips and Tricks to <A HREF="mailto:gazette@ssc.com">gazette@ssc.com</A></center>
<UL>
<!-- index_text begins -->
<li><A HREF="#tips/1"
><strong>Getting s-video to work on Win2k. Tip: working with tech support.</strong></a>
<li><A HREF="#tips/2"
><strong>Need to contact a hacker</strong></a>
<li><A HREF="#tips/3"
><strong>How do I create a new driver disk for RH7.1 network</strong></a>
<li><A HREF="#tips/4"
></a>Account field length in /etc/passwd --or--
<br><A HREF="#tips/4"
><strong>Maximum Username Limits in <TT>/etc/passwd</TT></strong></a>
<li><A HREF="#tips/5"
><strong>regarding "LINUX FOR THE PRODUCTION ENVIROMENT"</strong></a>
<li><A HREF="#tips/6"
><strong>MySQL Tips and Tricks - finding Linux Magazine</strong></a>
<li><A HREF="#tips/7"
><strong>Want to remove linux completly - GRUB still present</strong></a>
<li><A HREF="#tips/8"
><strong>lost linux password</strong></a>
<li><A HREF="#tips/9"
><strong>Re:prob in lilo booting</strong></a>
<li><A HREF="#tips/10"
><strong>I need an answer from you....</strong></a>
<li><A HREF="#tips/11"
><strong>Re: central logging and pipping to postgresql db</strong></a>
<li><A HREF="#tips/12"
><strong>Re: catch stdin</strong></a>
<li><A HREF="#tips/13"
><strong>Completely wiping the MBR using DOS debug</strong></a>
<li><A HREF="#tips/14"
><strong>MS Frontpage98 Server extention Redhat Linux 6.0 vs ASP</strong></a>
<li><A HREF="#tips/15"
><strong>YAHE: run BIND safely</strong></a>
<li><A HREF="#tips/16"
><strong>Linux solution to syncing with Exchange Address books as a client</strong></a>
<!-- index_text ends -->
</UL>
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="tips/1"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Getting s-video to work on Win2k. Tip: working with tech support.</FONT></H3>
Mon, 28 May 2001 11:33:29 -0400
<BR>Qustion From: Jonathan Van Luik
<br>Tip From: Ben Okopnik (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)
<P><STRONG>
I am trying to help out my friend use his Inspiron 3800. He wants to
display what is on his laptop onto the television to watch his dvd movies.
However, now that he has win2k on the laptop he cannot seem to get the fn+f5
button function to work. This should be very simple. Connect the s-video
to the t.v., and then push the button. But it isn't working, and I cannot
get Dell help since it is not my laptop.
</STRONG></P>
<blockquote><font color="#000066">Ben sent him a cheerfully silly note expressing that this is not the right
place for this question. See the Greeting From Heather Stern in this month's
TAG for more about that
<IMG SRC="../gx/dennis/smily.gif" ALT=";)"
height="24" width="20" align="middle">
-- Heather</font></blockquote>
<P>
Just as a possibly helpful aside, I've spoken to Dell tech support 20
times or more, never as an owner. I always start out the conversation
with "Hi, this is Ben Okopnik, and I'm the tech working on Mr. X's
machine." As long as you have the serial numbers, etc. that they're
asking for, there shouldn't be a problem; ask to speak to a supervisor
if there is one. There's absolutely no reason for them to deny you help,
especially if your friend is there with you.
</P>
<!-- sig -->
<!-- end 1 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="tips/2"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Need to contact a hacker</FONT></H3>
Thu, 7 Jun 2001 09:01:30 -0700
<BR>Question From: Kane Felix
<br>Tip From: Dan Wilder (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)
<!-- sig -->
<P>
On Thu, Jun 07, 2001 at 08:39:49AM -0000, Kane Felix wrote:
</P>
<P><STRONG>
I have been attempting to contact any hackers in the Tampabay, Orlando, FL
area. I have a project that needs some expert input, however, I have been
unsuccessful thus far. Is there a mailing list, or e-mail address listing
for this area I may locate? If so, please help me to locate it, or offer
any advice possible.
</STRONG></P>
<P>
Depends on which common meaning of the term "hacker" you intend.
For "expert code mechanic," try
</P>
<P>
<A HREF="http://www.linuxjournal.com/glue"
>http://www.linuxjournal.com/glue</A>
</P>
<P>
("Groups of Linux Users Everywhere") for a Linux user group in your
area.
</P>
<P>
Do you need to restrict yourself to your geographic area? Linux itself
is written by many people scattered all over the world. The Internet
provides a substitute for physical proximity. While a little long
in the tooth, the internet newsgroups still provide forums around which
many efforts coalesce. Check
</P>
<P>
<A HREF="http://groups.google.com/googlegroups/deja_announcement.html"
>http://groups.google.com/googlegroups/deja_announcement.html</A>
</P>
<P>
For mailing lists or other forums related to the subject matter
you're interested in, again check Google. A suitable search will
reveal various forums. Jump in, participate, you're quite likely
to find people who can assist you.
</P>
<P>
If your project is open source, consider registering it on SourceForge,
</P>
<P>
<A HREF="http://www.sourceforge.net"
>http://www.sourceforge.net</A>
</P>
<P>
which provides network CVS access, forums, and other services organized
around particular projects.
</P>
<P>
--
Dan Wilder
</P>
<!-- sig -->
<!-- end 2 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="tips/3"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">How do I create a new driver disk for RH7.1 network</FONT></H3>
Tue, 22 May 2001 15:15:21 -0700
<Br>Question From: Rick Lin
<BR>Tip From: Breen Mullins (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)
<!-- sig -->
<P><STRONG>
Hi there,
I am trying to do an upgrade on a working RH6.2 system, trying to upgrade
to RH7.1 by using the netboot.img (Install via FTP/HTTP/NFS),
when I get to the question "do you have a driver disk"
I insert the driver disk, but the drivers listed do not have the 3com 3c509
nic card listed
they all seem to be PCI nic cards.
</STRONG></P>
<P><STRONG>
How can I create a new driver disk for the 3c509 ISA card?
</STRONG></P>
<P>
Hi Rick --
</P>
<P>
See the README file from the RedHat CD. It points you to an additional
drivers.img file that you use to make another floppy. I'd guess that
the 3C509 driver is there.
</P>
<P>
HTH --
</P>
<P>
Breen
</P>
<!-- end 3 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="tips/4"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Maximum Username Limits in <TT>/etc/passwd</TT></FONT></H3>
Tue, 05 Jun 2001 12:07:20 -0700
<BR>Question From: Jos&eacute; Antonio P&eacute;rez Hern&aacute;ndez
<br>Tip From: Jim Dennis (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)
<!-- ::
Maximum Username Limits in <TT>/etc/passwd</TT>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
:: -->
<P><STRONG>
Hi,
</STRONG></P>
<P><STRONG>
I'd like to know how long is the account field in the <TT>/etc/passwd</TT> file
and if it can be modified: I'm trying to install a system that will
serve users distinguished with their registration code (14 chars or
more) instead of their usual user name.
</STRONG></P>
<P><STRONG>
Any tip is welcome.
TIA.
</STRONG></P>
<P><STRONG>
Jose Antonio.
</STRONG></P>
<P>
Under any reasonably recent Linux distribution (any glibc based one)
you can have usernames of up to 31 characters. I think you're
still required to have an initial alphabetic and I'd be very dubious
of any effort to use any characters other than alphanumerics and
maybe underscores.
</P>
<P>
However, I think the software that you're talking about is
bizarre in this requirement --- and I suspect that it's a severely
broken model that would lead UNIX software to impose constraints
on usernames beyond those implicit in the standard libraries.
</P>
<P>
BTW: Limitations on username lengths and similar issues are purely
a library and userspace issue. The kernel has no notion of usernames.
UID limits are primarily a kernel issue; although the libraries
naturally must implement to the kernel's requirements. Linux kernels
prior to 2.4 used a 16-bit UID (limits us to 65,536 distinct users).
In 2.4 this has been changed to a 32-bit value allowing us to use
upto 4-billion UIDs. Although its a rare system that needs to provide
access to more than 64K users --- there are fairly common administrative
requirements that UIDs be unique throughout the life of a company or
organization -- that they never be re-used or that they be retained for
seven years or whatever.
</P>
<P>
I realize that UID limits weren't part of your question; but they're
likely to be of interest to other readers, especially others who are
come across this in the search engines.
</P>
<p>-- Jim Dennis</p>
<!-- end 4 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="tips/5"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">regarding "LINUX FOR THE PRODUCTION ENVIROMENT"</FONT></H3>
Tue, 5 Jun 2001 17:01:15 -0400 (EDT)
<BR>toby cabot (<a href="mailto:linux-questions-only@ssc.com">toby from caboteria.org</a>)
<!-- sig -->
<P>
Folks,
</P>
<P>
I enjoy your column and invariably learn something from reading it, but
this time I can answer a question of yours!
</P>
<P>
In your answer to the "LINUX FOR THE PRODUCTION ENVIROMENT" question in
the June issue you asked what sql-ledger is. It's an accounting package
written in perl. It uses a relational database back-end (postgres,
maybe others) and the UI is cgi-scripts. It's pretty good; I used it
last year when I was consulting to cut and track some invoices. I'm not
an accountant but it seemed to work just fine for me, and it wasn't that
hard to figure out.
</P>
<P>
<A HREF="http://www.sql-ledger.org"
>http://www.sql-ledger.org</A>
</P>
<P>
Regards,
Toby Cabot
</P>
<!-- end 5 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="tips/6"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">MySQL Tips and Tricks - finding Linux Magazine</FONT></H3>
Wed, 6 Jun 2001 09:32:04 -0000
<BR> B&ouml;<EFBFBD>var Bj&ouml;rgvinsson (<a href="mailto:linux-questions-only@ssc.com">bodvar from atlanta.is</a>)
<!-- sig -->
<P>
For the English version og Linux Magazin(e):
<A HREF="http://www.linux-magazine.co.uk"
>http://www.linux-magazine.co.uk</A>
This was the only version I had seen until I came across this posting of
Linux being a German Mag.
</P>
<P>
HTH
</P>
<P>
Bodvar
</P>
<!-- sig -->
<!-- end 6 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="tips/7"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Want to remove linux completly - GRUB still present</FONT></H3>
11 Jun 2001 10:13:01 +0200
<BR>Question From: Chandina rodrigo
<br>Tip From: Huibert Alblas (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)
<P><STRONG><BLOCKQuote>
HI guys..
I formatted my machine and got rid of windows98 but
when i boot up i get to the command grub&gt; i'm a new
user with some undestanding of linux and windws.
i found this posted i tried this peice of code
</BLOCKQuote></STRONG></P>
<code><strong><font color="#000033"><br>dd if=/dev/zero of=/dev/hda bs=512 count=1
</font></strong></code>
<P><STRONG>
and it said Error: unrecognised command
</STRONG></P>
<P><STRONG>
guys i need to install windows again for some project
work so could u kindly tell me what i should type in
the grub&gt; so that i can do the normal fdisk with a
bootable floppy of win98/95
</STRONG></P>
<P><STRONG>
Thanks.!!
</STRONG></P>
<P>
This should be no problem,
</P>
<P>
this GRUB thing is the bootmanager installed by your linux distro,
grub is not linux, so it can not regonise the dd command.
Since you allready got rid of Linux
<IMG SRC="../gx/dennis/unsmily.gif" ALT=":-("
height="24" width="20" align="middle"> the only thinbg left is to
remove the bootmanager. The dd command would be the right one if you
were still using Linux.
</P>
<P>
Now, for the solution:
</P>
<blockquote><ul>
<li>-Take the win9X floppy,
<li>-boot from this floppy,
<li>-type: fdisk /mbr
<li>-repartition with fdisk (dont forget to keep 2 Gig for Linux (do not
<br> partion this explicidly, just leave it unused) in an extended
<br> partition in case you want to try linux again)
<li>-install M$ Windows...
<li>-get your projekt done
<li>-get Linux back on your PC (we are a Linux List, I have to say this :-)
</ul></blockquote>
<P>
Hope I could help,
</P>
<P>
Halb
</P>
<!-- end 7 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="tips/8"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">lost linux password</FONT></H3>
Mon, 11 Jun 2001 12:01:15 -0700
<br>Question From: Selim Javed
<BR>Tip From: Mike Orr (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)
<!-- sig -->
<P><STRONG>
dear sir
</STRONG></P>
<P><STRONG>
my linux passs forget
</STRONG></P>
<P><STRONG>
but
<br>i'm reboot &amp; booting single
</STRONG></P>
<P><STRONG><CODE>
bash command not access
</CODE></STRONG></P>
<P><STRONG>
pls help me
</STRONG></P>
<P>
What is the exact error message you're seeing?
</P>
<P>
What happens if you type this at the Lilo prompt?
</P>
<blockquote><pre>Lilo: linux init=/bin/sh
</pre></blockquote>
<!-- sig -->
<!-- sig -->
<!-- end 8 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="tips/9"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Re:prob in lilo booting</FONT></H3>
30 May 2001 10:41:25 +0200
<br>Question From: saravanan_n
<BR>Tip From: Huibert Alblas (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)
<!-- sig -->
<P><STRONG>
Dear sir,
</STRONG></P>
<P><STRONG>
I successfully installed windows 2000 and linux,but i need
</STRONG></P>
<P><STRONG>
dual booting facility,i have 20 gb seagate hardisk ,i partitioned my
hardisk as 5 gb for c: 10 gb for d: and for linux the rest of the space
i use,but while i overwrite the first sector,but this lilo partition is
not happening,it shows ur partion limit exceeds 1024 cylinders,so please
give assistance to do the same.
</STRONG></P>
<P><STRONG>
with regards
saravanan
</STRONG></P>
<P>
I hope I understand correctly that you managed to install both W2K and
some Linux distro. but get into problems dualbooting with Lilo.....
</P>
<P>
If you have an 'older' version of a linux distro, it probably hasnt got
over the '1024 cylinder problem' yet.
</P>
<P>
I hope you have a bootfloppy ready and working.
Then the only thing you have to do is:
</P>
<P><BLOCKQuote>
remove old Lilo
</BLOCKQuote></P>
<P>
goto <A HREF="http://freshmeat.net/projects/lilo"
>http://freshmeat.net/projects/lilo</A>
</P>
<P>
Download source, install, be happy
</P>
<P>
or ask follow up question right here....
</P>
<P>
the new versions of lilo have no problems on new PC's but as you are
running W2K this should be no problem...
</P>
<P>
Hope I could help..
</P>
<P>
Halb
</P>
<!-- end 9 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="tips/10"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">I need an answer from you....</FONT></H3>
Mon, 4 Jun 2001 22:35:28 -0700
<br>Question From: James G
<BR>Tip From: Don Marti (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)
<!-- sig -->
<P><STRONG><BLOCKQuote>
I am wondering if there is a way using CGI/Perl or C
to create a program that learns and mimics the packets
sent by programs like realplayer etc, and then be able
to modify the packets so that information like
destination, who sent it etc. I have read a lot on
packet swtiching, bridge proxies etc and I have no
idea on what to do.....
</BLOCKQuote></STRONG></P>
<P>
The first thing you want to learn is a packet sniffer, such as
ethereal:
<A HREF="http://www.ethereal.com"
>http://www.ethereal.com</A>
</P>
<P><DL><DT>
or tcpdump:
<DD><A HREF="http://www.tcpdump.org"
>http://www.tcpdump.org</A>
</DL></P>
<P>
That should give you some idea of what the proprietary application is
sending over the wire. Next, you'll want to experiment with mimicking
it. You can get the information you need to do this from the
excellent "Unix Network Programming" volume 1, by W. Richard Stevens.
(It's C-centric, but you can apply the ideas to other programming
languages too.)
</P>
<P>
<A HREF="http://vig.prenhall.com/catalog/professional/product/1"
>http://vig.prenhall.com/catalog/professional/product/1</A>,4096,013490012X,00.html
</P>
<P>
--
Don Marti
</P>
<!-- end 10 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="tips/11"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Re: central logging and pipping to postgresql db</FONT></H3>
Tue, 5 Jun 2001 19:02:16 -0700
<BR>Question From: control
<BR>Tip From: Don Marti (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)
<!-- sig -->
<P><STRONG><BLOCKQuote>
not only do i want to have a central logserver, i also want to find a
way to log these events to a postgresql database table--this includes
and is not limited to only "secure","messages" files but all syslogd
events. what should i do?
</BLOCKQuote></STRONG></P>
<P>
syslogd supports writing to a named pipe. See man syslog.conf. So,
you could write a script to read from the named pipe and do inserts
into the database.
</P>
<P>
If something bad happens to the database, you'll still want regular logs
to fall back on, so you should log the important stuff to files too.
</P>
<P>
--
Don Marti
</P>
<!-- end 11 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="tips/12"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Re: catch stdin</FONT></H3>
Thu, 7 Jun 2001 09:21:08 -0700
<br>Question From: sami
<BR>Tip From: Mike Orr (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)
<P><STRONG>
On Thu, Jun 07, 2001 at 06:59:12PM +0500, sami ullah jan wrote:
i need to do something like this:
</STRONG></P>
<P><STRONG><CODE>
telnet "host"
<BR>'catch' stdin
<BR>enter username
<BR>'catch' stdin
<BR>enter passwd
</CODE></STRONG></P>
<P><STRONG>
how do i go about 'catching' the stdin?
</STRONG></P>
<P>
It sounds like you want a script to automatically log into one place.
There are a few possibilities:
</P>
<P><BLOCKQuote>
1) The 'expect' program allows a script to wait for certain characters
from the host (e.g., "ogin:" or "ssword:") and then send the specified
text. That's usually used for programs that want the entire session
under program control. Whether you can use 'expect' to log in and then
switch to interactive mode, I don't know.
</BLOCKQuote></P>
<P>
2) If you use ssh instead of telnet, you can set up your account on
'host' so that it will allow you to log into it without having to type
a password. See "man ssh".
</P>
<P>
--
Mike Orr
</P>
<P><STRONG>
hi,
thanx for the quick reply before. u guys are doig a great job.
</STRONG></P>
<P><STRONG>
QS. how do u go about writing on the soundcard? what do u need to know? i
presume its not as simple as writing to a terminal device.
</STRONG></P>
<P><STRONG>
thanx,
sami.
</STRONG></P>
<!-- end 12 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="tips/13"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Completely wiping the MBR using DOS debug</FONT></H3>
Sat, 9 Jun 2001 15:36:11 +0100 (BST)
<BR>Chandima rodrig&oacute; (<a href="mailto:linux-questions-only@ssc.com">sri_prince007 from yahoo.com</a>)
<!-- sig -->
<P>
hey guys.... i go it!!! I'm in love with linux!!
i found the code on site.. sorry for the bother...
this part of code did the trick!!
yep it was ben who had given the link thanx fellow!!
made my day!!
</P>
<P>
regard.
rodrigo!!
</P>
<P>
Boot with a DOS floppy that has "debug" on it; run
"debug". At the '-' prompt, "block-fill" a 512-byte
chunk of memory with zeroes:
</P>
<blockquote><code><font color="#000033"><br>f 9000:0 200 0
</font></code></blockquote>
<P>
Start assembly mode with the 'a' command, and enter
the following code:
</P>
<blockquote><code><font color="#000033"><br>mov dx,9000
<br>mov es,dx
<br>xor bx,bx
<br>mov cx,0001
<br>mov dx,0080
<br>mov ax,0301
<br>int 13
<br>int 20
</font></code></blockquote>
<P>
Press &lt;Enter&gt; to exit assembly mode, take a deep
breath - and press "g" to execute, then "q" to quit
"debug". Your HD is now in a virgin state, and ready
for partitioning and installation.
</P>
<blockquote><font color="#000066">Glad I could help, Rodrigo (or is that 'rodrigo!!'?
<IMG SRC="../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
-=- Ben Okopnik!!
</font></blockquote>
<!-- end 13 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="tips/14"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">MS Frontpage98 Server extention Redhat Linux 6.0 vs ASP</FONT></H3>
Thu, 31 May 2001 16:00:39 -0400 (EDT)
<br>QUestion From: Francois
<BR>Tip From: Daniel S. Washko (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)
<!-- sig -->
<P><STRONG>
Hi
I am currently running MS Frontpage98 Server extension Redhat Linux 6.0
(<A HREF="http://www.apache.org/">Apache</A>) I would like to know if it is possible to run ASP on the same
configuration. Would it be a Frontpage Upgrade or would it be on the
Linux Side and is it major changes?. Any help would be highly
appreciated.
Thanx
</STRONG></P>
<P><STRONG>
Francois
</STRONG></P>
<P>
You should be able to build apache with both Frontpage98 and ASP, but you
will need to add mod_perl first. Check out this site:
<A HREF="http://www.nodeworks.com/asp"
>http://www.nodeworks.com/asp</A>
</P>
<P>
--
Daniel S. Washko
</P>
<!-- end 14 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="tips/15"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">YAHE: run BIND safely</FONT></H3>
Tue, 05 Jun 2001 08:04:47 -0700
<BR>Benjamin D. Smith (<a href="mailto:linux-questions-only@ssc.com">amp from benjamindsmith.com</a>)
<!-- sig -->
<P>
(Yet Another "Helpful" Email)
</P>
<P>
BIND sucks, and we all know it, even though it is a core piece of
infrastructure to the 'net. Bind 9 looks good, but I don't quite yet
feel ready to deploy it. Instead, run BIND in a chroot jail - so even
if it gets hacked, they don't "get" anything.
</P>
<P><DL><DT>
There's a howto at linuxdoc.org:
<DD><A HREF="http://www.linuxdoc.org/HOWTO/Chroot-BIND-HOWTO.html"
>http://www.linuxdoc.org/HOWTO/Chroot-BIND-HOWTO.html</A>
</DL></P>
<P>
-Ben
</P>
<blockquote><font color="#000066">Thanks Ben, and for your thoughts on the learning curve of Windows vs.
UNIX type systems, posted in the Mailbag this month. Just about any
dangerous daemon might be a tiny bit safer in a chroot jail. It's not
a perfect trap without some use of the 'capabilities' (privileges really)
in newer kernels, but it's pretty good.
-- Heather</font></blockquote>
<!-- end 15 -->
<!-- .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~. -->
<P> <A NAME="tips/16"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Linux solution to syncing with Exchange Address books as a client</FONT></H3>
Tue, 22 May 2001 20:20:53 -0700
<BR>Question From: Alan Maddison
<BR>Tip From: Heather Stern (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)
<P><STRONG>
James
</STRONG></P>
<P><STRONG>
I hope that you can help me find a solution before I'm forced back to NT. I
have to find a Linux solution that will allow me to connect to an Exchange
server over the WAN and then sync address books.
</STRONG></P>
<P><STRONG>
Any suggestions?
</STRONG></P>
<P><STRONG>
Thanks.
</STRONG></P>
<P><STRONG>
Alan Maddison
</STRONG></P>
<blockquote><font color="#000066">Well, we've had numerous past articles address the matter of <EM>replacing</EM>
an Exchange server with a Linux box, but you're asking about being
a <EM>client</EM> to one...
</font></blockquote>
<blockquote><font color="#000066">And I can't just point you at the Gazette search engine
<IMG SRC="../gx/dennis/unsmily.gif" ALT=":("
height="24" width="20" align="middle"> because "Exchange"
is way too common a word. MX records and the server side of this question
will flood you, even without people just using the word for its real meaning.
</font></blockquote>
<blockquote><font color="#000066">But, we had a mention in a past issue
(<A HREF="../issue58/lg_tips58.html#2c/6"
>http://www.linuxgazette.com/issue58/lg_tips58.html#2c/6</A>) about Bynari having
a good one - they also have a server product. So I think you might find the
Insight client to be just what you need! (<A HREF="http://www.bynari.com"
>http://www.bynari.com</A>)
</font></blockquote>
<blockquote><font color="#000066">I post it again because I have to update you ... it's <EM>not</EM> free - you have to
pay them for their hard work in getting the protocols right. Their website
has a "price special" but it appears to have expired a month ago, so I have
no idea what they cost, but it's probably not trying to be too expensive.
-- Heather</font></blockquote>
<!-- end 16 -->
<P> <hr> </p>
<!-- *** BEGIN copyright *** -->
<H5 align="center">This page edited and maintained by the Editors
of <I>Linux Gazette</I>
<a href="http://www.linuxgazette.com/copying.html"
>Copyright &copy;</a> 2001
<BR>Published in issue 68 of <I>Linux Gazette</I> July 2001</H5>
<H6 ALIGN="center">HTML script maintained by
<A HREF="mailto:star@starshine.org">Heather Stern</a> of
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</H6>
<!-- *** 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="jennysknee.jpg" SRC="misc/collinge/jennysknee.jpg"
WIDTH="750" HEIGHT="303">
<BR CLEAR="all">
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<BR CLEAR="all">
<P> More HelpDex cartoons are at
<A HREF="http://www.shanecollinge.com/Linux">http://www.shanecollinge.com/Linux</A>.
<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Shane Collinge</H4>
<CITE>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.</CITE>
<!-- *** END bio *** -->
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2001, Shane Collinge.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 68 of <i>Linux Gazette</i>, July 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">Journalling Filesystems for Linux</font></H1>
<H4>By <a href="mailto:matt@martine2.difi.unipi.it">Matteo Dell'Omodarme</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<h1 align=center>Introduction</h1>
A filesystem is the software used to organize and manage
the data stored on disk drives; it ensures the
integrity of the data providing that data written
to disk is identical when it is read
back. In addition to storing the data contained in files, a filesystem
also stores and manages important
information about the files and about the filesystem
itself (i.e. date and time stamps, ownership, access permissions,
the file's size and the storage location or locations on
disk, and so on). This information is commonly referred to as metadata. <p>
Since a filesystem tries to work as asynchronous as possible, in order to
avoid hard-disk bottleneck, a sudden interruption of its
work could result in a loss of data.
As an example, let's consider the following scenario: what happens if your machine crashes
when you are working on a document residing on a Linux standard ext2
filesystem? <br>
There are several answers:
<ul>
<li> The machine crashes after you saved the file. This is the best
scenario: you haven't lost anything. Just reboot the machine and
continue working on the document. <P>
<li>The machine crashes before you saved the file.
You have lost all your changes but your old version is still ok. <P>
<li>The machine crashes during the
exact moment when the file is being written.
This is the worst case: the new version of the file is
physically overwriting the old version. You end up with a file
partially new and partially old. If the file was written in a binary form
you can't reopen it because the internal format of
its data is inconsistent with what the application expects. <P>
</ul>
In this last scenario things can be even worse if the drive was
writing the metadata areas, such
as the directory itself. Now instead of one corrupted file, you have one
corrupted filesystem and you can lose an entire directory
or all the data on an entire disk partition.<p>
The standard Linux filesystem (ext2fs) makes an attempt to prevent
and recover from the metadata corruption case performing an extensive
filesystem analysis (fsck) during bootup.
Since ext2fs incorporates redundant copies of critical
metadata, it is extremely unlikely for that data to be completely
lost. The system figures out where the corrupt metadata is, and then
either repairs the damage by copying from the redundant version or
simply deletes the file or files whose metadata is affected. <p>
Obviously, the larger is the filesystem to check, the longer
the check process. On a partition of several gigabytes it may
take a great deal of time to check the metadata during bootup.<br>
As
Linux begins to take on more complex applications, on larger servers,
and with less tolerance for downtime, there is a need for more
sophisticated filesystems that do an even better job of protecting data
and metadata.<p>
The journalling filesystems available for Linux are the
answer to this need.
<h1 align=center>What is a journalling filesystem?</h1>
Here is reported only a general introduction to journalling. For more
specific and technical notes please see Juan I. Santos Florido
article in <a
href="../issue55/florido.html">Linux Gazette 55</a>.
Other information can be obtained from
<a href="http://freshmeat.net/articles/view/212/">freshmeat.net/articles/view/212/</a>.<p>
Most modern filesystems use journalling techniques borrowed from the
database world to improve crash
recovery. Disk transactions are written sequentially to an area of
disk called <em>journal</em> or <em>log</em> before being
written to their final locations within the filesystem. <br>
Implementations vary in terms of what data is
written to the log. Some implementations write only the filesystem
metadata, while others record all writes to the journal.<p>
Now, if a crash happens before
the journal entry is committed, then the original data is still on the
disk and you lost only
your new changes.
If the
crash happens during the actual disk update (i.e. after the journal
entry was committed), the journal
entry shows what was supposed to have happened. So when the
system reboots, it can simply replay the journal entries and complete the
update that was interrupted. <p>
In either case, you have valid data and not a trashed partition.
And since the recovery time associated with this log-based approach is
much shorter, the system is on line in few seconds.<p>
It is also important to note that using a journalling filesystem does not
entirely obsolete the use of filesystem
checking programs (fsck). Hardware and software errors that corrupt random
blocks in the filesystem are not
generally recoverable with the transaction log.
<h1 align=center>Available journalling filesystems</h1>
In the following part I will consider three journalling filesystems.<p>
The first one is <b>ext3</b>. Developed by Stephen Tweedie, a leading
Linux kernel developer, ext3 adds journalling into ext2.
It is available in alpha
form at
<a href="ftp://ftp.linux.org.uk/pub/linux/sct/fs/jfs/">ftp.linux.org.uk/pub/linux/sct/fs/jfs/</a>.<p>
Namesys has a journalling filesystem under development called
<b>ReiserFS</b>. It is available at
<a href="http://www.namesys.com/">www.namesys.com</a>.<p>
SGI has released on May 1 2001 version 1.0 of its <b>XFS</b> filesystem for
Linux. You can find it at
<a href="oss.sgi.com/projects/xfs/">oss.sgi.com/projects/xfs/</a>.<p>
In this article these three solutions are tested and benchmarked using
two different programs. <p>
<h1 align=center>Installing ext3</h1>
For technical notes about ext3 filesystem please refer to Dr.
Stephen Tweedie's <a
href="ftp://ftp.kernel.org/pub/linux/kernel/people/sct/ext3/">paper</a>
and to his
<a href=http://olstrans.sourceforge.net/release/OLS2000-ext3/OLS2000-ext3.html">talk</a>.
<p>
The ext3 filesystem is directly derived from its ancestor, ext2. It has
the valuable characteristic to be absolutely backward compatible to
ext2 since it is just an ext2 filesystem with journalling.
The obvious drawback is that ext3 doesn't implement any of the modern
filesystem features which increase data manipulation speed and packing. <p>
ext3 comes as a patch of
2.2.19 kernel, so first of all, get a linux-2.2.19 kernel from
<a href="ftp://ftp.kernel.org/pub/linux/kernel/v2.2/">ftp.kernel.org</a>
or from one of its <a href="http://www.kernel.org/mirrors/">mirrors</a>.
The patch is available at <a
href="ftp://ftp.linux.org.uk/pub/linux/sct/fs/jfs/">ftp.linux.org.uk/pub/linux/sct/fs/jfs</a>
or <a
href="ftp://ftp.kernel.org/pub/linux/kernel/people/sct/ext3">ftp.kernel.org/pub/linux/kernel/people/sct/ext3</a>
or from one mirror of this site.<br>
From one of these sites you need to get the following files:
<ul>
<li><a
href="ftp://ftp.kernel.org/pub/linux/kernel/people/sct/ext3/ext3-0.0.7a.tar.bz2">ext3-0.0.7a.tar.bz2</a>:
the kernel patch.
<li><a
href="ftp://ftp.kernel.org/pub/linux/kernel/people/sct/ext3/e2fsprogs-1.21-WIP-0601.tar.bz2">e2fsprogs-1.21-WIP-0601.tar.bz2</a>:
the e2fsprogs suite with ext3 support.
</ul>
Copy Linux kernel linux-2.2.19.tar.bz2 and ext3-0.0.7a.tar.bz2 files to
<em>/usr/src</em> directory and extract them:
<pre>
mv linux linux-old
tar -Ixvf linux-2.2.19.tar.bz2
tar -Ixvf ext3-0.0.7a.tar.bz2
cd linux
cat ../ext3-0.0.7a/linux-2.2.19.kdb.diff | patch -sp1
cat ../ext3-0.0.7a/linux-2.2.19.ext3.diff | patch -sp1
</pre>
The first diff is copy of SGI's kdb kernel debugger patches. The
second one is the ext3 filesystem. <br>
Now, configure the kernel, saying YES to "Enable Second extended fs
development code" in the filesystem section, and build it.<p>
After the kernel is compiled and installed you should make and install
the e2fsprogs:
<pre>
tar -Ixvf e2fsprogs-1.21-WIP-0601.tar.bz2
cd e2fsprogs-1.21
./configure
make
make check
make install
</pre>
That's all. The next step is to make an ext3 filesystem in a partition.
Reboot with the new kernel. Now you have two options: make a
new journalling filesystem or journal an existing one. <br>
<ul>
<li>Making a new ext3 filesystem. Just use the mke2fs from the
installed e2fsprogs, and use the "-j" option when running mke2fs:
<pre>
mke2fs -j /dev/xxx
</pre>
where /dev/xxx is the device where you would create the ext3 filesystem.
The "-j" flag tells mke2fs to create an ext3 filesystem with a hidden
journal. You could control the size of the journal using the optional
flag -Jsize=&lt;n&gt; (n is the preferred size of the journal in Mb).
<li>Upgrade an existing ext2 filesystem to ext3. Just use tune2fs:
<pre>
tune2fs -j /dev/xxx
</pre>
You should do that either on mounted or unmounted filesystem. If the
filesystem is mounted a file .journal is created in the top-level
directory of the filesystem; if it is unmounted a hidden system inode
is used for the journal. In such a way all the data in the filesystem
are preserved.
</ul>
You can mount the ext3 filesystem using the command:
<pre>
mount -t ext3 /dev/xxx /mount_dir
</pre>
Since ext3 is basically ext2 with journalling, a cleanly unmounted ext3
filesystem could be remounted as ext2 without any other commands.
<h1 align=center>Installing XFS</h1>
For a technical overview of XFS filesystem refer to <a
href="http://linux-xfs.sgi.com/projects/xfs/">SGI linux XFS page</a>
and to <a
href="http://linux-xfs.sgi.com/projects/xfs/publications.html">SGI
publications page</a>.<br>
Also see the <a href="http://oss.sgi.com/projects/xfs/faq.html">FAQ page</a>.
<p>
XFS is a journalling filesystem for Linux available from SGI.
It is a mature technology that has been proven on
IRIX systems as the default filesystem for all SGI customers.
XFS is licensed under GPL. <br>
XFS Linux 1.0 is released for the Linux 2.4 kernel, and I tried the
2.4.2 patch. So the first step is to acquire a linux-2.4.2 kernel from one
mirror of kernel.org.<br>
The patches are at <a
href="ftp://oss.sgi.com/projects/xfs/download/Release-1.0/patches/">oss.sgi.com/projects/xfs/download/Release-1.0/patches</a>.
From this directory download:
<ul>
<li>
<a
href="ftp://oss.sgi.com/projects/xfs/download/Release-1.0/patches/linux-2.4-xfs-1.0.patch.gz">linux-2.4-xfs-1.0.patch.gz</a>
<li>
<a
href="ftp://oss.sgi.com/projects/xfs/download/Release-1.0/patches/linux-2.4.2-core-xfs-1.0.patch.gz">linux-2.4.2-core-xfs-1.0.patch.gz</a>
<li>
<a
href="ftp://oss.sgi.com/projects/xfs/download/Release-1.0/patches/linux-2.4.2-kdb-04112001.patch.gz">linux-2.4.2-kdb-04112001.patch.gz</a>
</ul>
Copy the Linux kernel linux-2.4.2.tar.bz2 in <em>/usr/src</em> directory, rename the
existing linux directory to linux-old and extract the new kernel:
<pre>
mv linux linux-old
tar -Ixf inux-2.4.2.tar.bz2
</pre>
Copy each patch in the top directory of your linux source tree
(i.e. /usr/src/linux) and apply them:
<pre>
zcat patchfile.gz | patch -p1
</pre>
Then configure the kernel, enabling the options "XFS
filesystem support" (CONFIG_XFS_FS) and "Page Buffer support"
(CONFIG_PAGE_BUF) in the filesystem section.
Note that you will also need to upgrade the following system utilities to
these versions or later:
<ul>
<li><a
href="http://www.kernel.org/pub/linux/utils/kernel/modutils/v2.4/">modutils-2.4.0</a>
<li><a href="http://www.gnu.org/software/autoconf/autoconf.html">autoconf-2.13</a>
<li><a href="http://e2fsprogs.sourceforge.net/">e2fsprogs-devel-1.18</a>
</ul>
Install the new kernel and reboot.<br>
Now download the <a
href="ftp://oss.sgi.com/projects/xfs/download/Release-1.0/cmd_tars/xfsprogs-1.2.0.src.tar.gz">xfs
progs tools</a>. This tarball contains a set of commands to use the
XFS filesystem, such as mkfs.xfs. To build them:
<pre>
tar -zxf xfsprogs-1.2.0.src.tar.gz
cd xfsprogs-1.2.0
make configure
make
make install
</pre>
After installing this set of commands you can create a new XFS
filesystem with the command:
<pre>
mkfs -t xfs /dev/xxx
</pre>
One important option that you may need is "-f" which will force the
creation of a new filesystem, if a filesystem already exists on that
partition. Again, note that this will destroy all data currently on
that partition:
<pre>
mkfs -t xfs -f /dev/xxx
</pre>
You can then mount the new filesystem with the command:
<pre>
mount -t xfs /dev/xxx /mount_dir
</pre>
<h1 align=center>Installing ReiserFS</h1>
For technical notes about reiserFS refer to <a
href="http://www.namesys.com/">NAMESYS home page</a>
and to <a
href="http://www.namesys.com/faq.html">FAQ page</a>.<p>
ReiserFS has been in the official Linux kernel since
2.4.1-pre4. You always need to get the utils (e.g. mkreiserfs to
create ReiserFS on an empty partition, the resizer, etc.).<br>
The up-to-date ReiserFS version is available as a patch against either
2.2.x and 2.4.x kernels. I tested the patch against 2.2.19 Linux kernel.<p>
The first step, as usual, is to get a linux-2.2.19.tar.bz2 standard
kernel from a mirror of kernel.org.
Then get the reiserfs <a
href="ftp://ftp.namesys.com/pub/reiserfs-for-2.2/">2.2.19
patch</a>. At present time the last patch is 3.5.33.<br>
Please note that, if you choose to get the patch against 2.4.x kernel,
you should get also the utils tarball <a
href="ftp://ftp.namesys.com/pub/reiserfsprogs/reiserfsprogs-3.x.0j.tar.gz
">reiserfsprogs-3.x.0j.tar.gz</a>. <br>
Now unpack the kernel and the patch. Copy the tarballs in <em>/usr/src</em> and
move the linux directory to linux-old; then run the commands:
<pre>
tar -Ixf linux-2.2.19.tar.bz2
bzcat linux-2.2.19-reiserfs-3.5.33-patch.bz2 | patch -p0
</pre>
Compile the Linux kernel setting reiserfs support on filesystem section.<br>
Compile and install the reiserfs utils:
<pre>
cd /usr/src/linux/fs/reiserfs/utils
make
make install
</pre>
Install the new kernel and reboot.
Now you can create a new reiserfs filesystem with the command:
<pre>
mkreiserfs /dev/xxxx
</pre>
and mount it:
<pre>
mount -t reiserfs /dev/xxx /mount_dir
</pre>
<h1 align=center>Filesystems benchmark</h1>
For the test I used a Pentium III - 16 Mb RAM - 2 Gb HD with a Linux RedHat 6.2 installed. <br>
All the filesystems worked fine for me, so I started a little benchmark
analysis to compare their performances. As a first test I simulated a
crash turning off the power, in order to control the journal
recovery process. All filesystems passed successfully this phase and
the machine was on line in few
seconds with each filesystem. <p>
The next step is a benchmark analysis using bonnie++ program,
available at <a href="http://www.coker.com.au/bonnie++/">www.coker.com.au/bonnie++</a>.
The program tests database type access to a single file, and it tests
creation, reading, and
deleting of small files
which can simulate the usage of programs such as Squid, INN, or
Maildir-format programs (qmail). <br>
The benchmark command was:
<pre>
bonnie++ -d/work1 -s10 -r4 -u0
</pre>
which executes the test using 10Mb (-s10) in the
filesystem mounted in /work1 directory. So, before launching the
benchmark, you must create the requested filesystem on a partition
and mount it on /work1 directory. The other flags specify the RAM
amount in Mb (-r4) and the user (-u0, i.e. run as root).<p>
The results are shown in the following table.<p>
<table BORDER=3 CELLPADDING=2 NOSAVE >
<tr NOSAVE>
<td COLSPAN="2" NOSAVE class="header"></td>
<td COLSPAN="6" class="header"><b><font size=+2>Sequential Output</font></b></td>
<td COLSPAN="4" class="header"><b><font size=+2>Sequential Input</font></b></td>
<td COLSPAN="2" ROWSPAN="2" class="header"><b><font size=+2>Random</font></b>
<br><b><font size=+2>Seeks</font></b></td>
</tr>
<tr ALIGN=CENTER NOSAVE>
<td NOSAVE></td>
<td>Size:Chunk Size</td>
<td COLSPAN="2" BGCOLOR="#FFCC00" NOSAVE>Per Char</td>
<td COLSPAN="2" BGCOLOR="#FFFF00" NOSAVE>Block</td>
<td COLSPAN="2" BGCOLOR="#CCFFFF" NOSAVE>Rewrite</td>
<td COLSPAN="2" BGCOLOR="#FFCC00" NOSAVE>Per Char</td>
<td COLSPAN="2" BGCOLOR="#FFFF00" NOSAVE>Block</td>
</tr>
<tr>
<td COLSPAN="2"></td>
<td class="ksec"><font size=-2>K/sec</font></td>
<td class="ksec"><font size=-2>% CPU</font></td>
<td class="ksec"><font size=-2>K/sec</font></td>
<td class="ksec"><font size=-2>% CPU</font></td>
<td class="ksec"><font size=-2>K/sec</font></td>
<td class="ksec"><font size=-2>% CPU</font></td>
<td class="ksec"><font size=-2>K/sec</font></td>
<td class="ksec"><font size=-2>% CPU</font></td>
<td class="ksec"><font size=-2>K/sec</font></td>
<td class="ksec"><font size=-2>% CPU</font></td>
<td class="ksec"><font size=-2>/ sec</font></td>
<td class="ksec"><font size=-2>% CPU</font></td>
</tr>
<tr>
<td class="rowheader"><b><font size=+1>ext2</font></b></td>
<td BGCOLOR="#FFCCFF" NOSAVE class="size">10M</td>
<td>1471</td>
<td>97</td>
<td>14813</td>
<td>67</td>
<td>1309</td>
<td>14</td>
<td>1506</td>
<td>94</td>
<td>4889</td>
<td>15</td>
<td>309.8</td>
<td>10</td>
</tr>
<tr>
<td class="rowheader"></td>
<td class="size"></td>
<td></td>
</tr>
<tr>
<td class="rowheader"><b><font size=+1>ext3</font></b></td>
<td BGCOLOR="#FFCCFF" NOSAVE class="size">10M</td>
<td>1366</td>
<td>98</td>
<td>2361</td>
<td>38</td>
<td>1824</td>
<td>22</td>
<td>1482</td>
<td>94</td>
<td>4935</td>
<td>14</td>
<td>317.8</td>
<td>10</td>
</tr>
<tr>
<td class="rowheader"></td>
<td class="size"></td>
<td></td>
</tr>
<tr>
<td class="rowheader"><b><font size=+1>xfs</font></b></td>
<td BGCOLOR="#FFCCFF" NOSAVE class="size">10M</td>
<td>1206</td>
<td>94</td>
<td>9512</td>
<td>77</td>
<td>1351</td>
<td>33</td>
<td>1299</td>
<td>98</td>
<td>4779</td>
<td>80</td>
<td>229.1</td>
<td>11</td>
</tr>
<tr>
<td class="rowheader"></td>
<td class="size"></td>
<td></td>
</tr>
<tr>
<td class="rowheader"><b><font size=+1>reiserfs</font></b></td>
<td BGCOLOR="#FFCCFF" NOSAVE class="size">10M</td>
<td>1455</td>
<td>99</td>
<td>4253</td>
<td>31</td>
<td>2340</td>
<td>26</td>
<td>1477</td>
<td>93</td>
<td>5593</td>
<td>26</td>
<td>174.3</td>
<td>5</td>
</tr>
</table>
<p>
<table BORDER=3 CELLPADDING=2 NOSAVE >
<tr NOSAVE>
<td COLSPAN="2" class="header"></td>
<td COLSPAN="6" class="header"><b><font size=+2>Sequential Create</font></b></td>
<td COLSPAN="6" class="header"><b><font size=+2>Random Create</font></b></td>
</tr>
<tr>
<td> </td>
<td>Num Files</td>
<td COLSPAN="2" BGCOLOR="#66FF99" NOSAVE>Create</td>
<td COLSPAN="2" BGCOLOR="#33FF33" NOSAVE>Read</td>
<td COLSPAN="2" BGCOLOR="#33CC00" NOSAVE>Delete</td>
<td COLSPAN="2" BGCOLOR="#66FF99" NOSAVE>Create</td>
<td COLSPAN="2" BGCOLOR="#33FF33" NOSAVE>Read</td>
<td COLSPAN="2" BGCOLOR="#33CC00" NOSAVE>Delete</td>
</tr>
<tr>
<td></td>
<td> </td>
<td class="ksec"><font size=-2>/ sec</font></td>
<td class="ksec"><font size=-2>% CPU</font></td>
<td class="ksec"><font size=-2>/ sec</font></td>
<td class="ksec"><font size=-2>% CPU</font></td>
<td class="ksec"><font size=-2>/ sec</font></td>
<td class="ksec"><font size=-2>% CPU</font></td>
<td class="ksec"><font size=-2>/ sec</font></td>
<td class="ksec"><font size=-2>% CPU</font></td>
<td class="ksec"><font size=-2>/ sec</font></td>
<td class="ksec"><font size=-2>% CPU</font></td>
<td class="ksec"><font size=-2>/ sec</font></td>
<td class="ksec"><font size=-2>% CPU</font></td>
</tr>
<tr>
<td class="rowheader"><b><font size=+1>ext2</font></b></td>
<td BGCOLOR="#FFCCFF" NOSAVE>16</td>
<td>94</td>
<td>99</td>
<td>278</td>
<td>99</td>
<td>492</td>
<td>97</td>
<td>95</td>
<td>99</td>
<td>284</td>
<td>100</td>
<td>93</td>
<td>41</td>
</tr>
<tr>
<td class="rowheader"><b><font size=+1>ext3</font></b></td>
<td BGCOLOR="#FFCCFF" NOSAVE>16</td>
<td>89</td>
<td>98</td>
<td>274</td>
<td>100</td>
<td>458</td>
<td>96</td>
<td>93</td>
<td>99</td>
<td>288</td>
<td>99</td>
<td>97</td>
<td>45</td>
</tr>
<tr>
<td class="rowheader"><b><font size=+1>xfs</font></b></td>
<td BGCOLOR="#FFCCFF" NOSAVE >16</td>
<td>92</td>
<td>99</td>
<td>251</td>
<td>96</td>
<td>436</td>
<td>98</td>
<td>91</td>
<td>99</td>
<td>311</td>
<td>99</td>
<td>90</td>
<td>41</td>
</tr>
<tr>
<td class="rowheader"><b><font size=+1>reiserfs</font></b></td>
<td BGCOLOR="#FFCCFF" NOSAVE>16</td>
<td>1307</td>
<td>100</td>
<td>8963</td>
<td>100</td>
<td>1914</td>
<td>99</td>
<td>1245</td>
<td>99</td>
<td>9316</td>
<td>100</td>
<td>1725</td>
<td>100</td>
</tr>
</table>
<p>
Two data are shown for each test: the speed of the filesystem (in
K/sec) and the CPU usage (in %). The higher the speed the better the
filesystem. The opposite is true for the CPU usage. <br>
As you can see reiserFS reports a hands down victory in managing files
(section <em>Sequential Create</em> and <em>Random Create</em>),
overwhelming its opponents by a factor higher than 10. In addition to
that is almost as good as the other filesystem in the <em>Sequential
Output</em> and <em>Sequential Input</em>.
There isn't any significant difference among the other filesystems. XFS
speed is similar to ext2 filesystem, and ext3 is, as expected, a
little slower than ext2 (it is basically the same thing, and it wastes
some time during the journalling calls). <p>
As a last test I get the mongo benchmark program available at reiserFS
benchmark page at
<a href="http://www.namesys.com">www.namesys.com</a>,
and I modified it in order to test the three journalling filesystems. I
inserted in the mongo.pl perl script the commands to mount the xfs and
ext3 filesystem and to format them. Then I started a benchmark analysis.<br>
The script formats partition /dev/xxxx, mounts it and runs given number
of processes during each phase: Create, Copy, Symlinks, Read, Stats,
Rename and Delete. Also, the program calculates fragmentation after Create
and Copy phases:
<pre>
Fragm = number_of_fragments / number_of_files
</pre>
You can find the same results in the directory <em>results</em> in the files:
<pre>
log - raw results
log.tbl - results for compare program
log_table - results in table form
</pre>
The tests was executed as in the following example:
<pre>
mongo.pl ext3 /dev/hda3 /work1 logext3 1
</pre>
where ext3 must be replaced by reiserfs or xfs in order to test the
other filesystems. The other arguments are the device to mount, where
the filesystem to test is located, the mounting directory, the
filename where the results are stored and the number of processes to
start.<p>
In the following tables there are the results of this analysis. The data
reported is time (in sec). The lower the value, the better the
filesystem.
In the first table the median dimension of files managed is 100 bytes, in the
second one it is 1000 bytes and in the last one 10000 bytes.<p>
<table BORDER NOSAVE >
<tr ALIGN=LEFT VALIGN=TOP NOSAVE>
<td NOSAVE><tt></tt>
<br><font size=-1></font></td>
<td BGCOLOR="#FFCCFF" NOSAVE><tt>ext3</tt>
<br><tt><font size=-1>files=68952</font></tt>
<br><tt><font size=-1>size=100 bytes</font></tt>
<br><tt><font size=-1>dirs=242</font></tt></td>
<td BGCOLOR="#FFCCFF" NOSAVE><tt>XFS</tt>
<br><tt><font size=-1>files=68952</font></tt>
<br><tt><font size=-1>size=100 bytes</font></tt>
<br><tt><font size=-1>dirs=241</font></tt></td>
<td BGCOLOR="#FFCCFF" NOSAVE><tt>reiserFS</tt>
<br><tt><font size=-1>files=68952</font></tt>
<br><tt><font size=-1>size=100 bytes</font></tt>
<br><tt><font size=-1>dirs=241</font></tt></td>
</tr>
<tr>
<td><tt>Create</tt></td>
<td>90.07</td>
<td>267.86</td>
<td>53.05</td>
</tr>
<tr>
<td><tt>Fragm.</tt></td>
<td>1.32</td>
<td>1.02</td>
<td>1.00</td>
</tr>
<tr>
<td><tt>Copy</tt></td>
<td>239.02</td>
<td>744.51</td>
<td>126.97</td>
</tr>
<tr>
<td><tt>Fragm.</tt></td>
<td>1.32</td>
<td>1.03</td>
<td>1.80</td>
</tr>
<tr>
<td><tt>Slinks</tt></td>
<td>0</td>
<td>203.54</td>
<td>105.71</td>
</tr>
<tr>
<td><tt>Read</tt></td>
<td>782.75</td>
<td>1543.93</td>
<td>562.53</td>
</tr>
<tr>
<td><tt>Stats</tt></td>
<td>108.65</td>
<td>262.25</td>
<td>225.32</td>
</tr>
<tr>
<td><tt>Rename</tt></td>
<td>67.26</td>
<td>205.18</td>
<td>70.72</td>
</tr>
<tr>
<td><tt>Delete</tt></td>
<td>23.80</td>
<td>389.79</td>
<td>85.51</td>
</tr>
</table>
<p>
<table BORDER NOSAVE >
<tr ALIGN=LEFT VALIGN=TOP NOSAVE>
<td NOSAVE><tt></tt>
<br></td>
<td BGCOLOR="#FFCCFF" NOSAVE><tt>ext3</tt>
<br><tt><font size=-1>files=11248</font></tt>
<br><tt><font size=-1>size=1000 bytes</font></tt>
<br><tt><font size=-1>dirs=44</font></tt></td>
<td BGCOLOR="#FFCCFF" NOSAVE><tt>XFS</tt>
<br><tt><font size=-1>files=11616</font></tt>
<br><tt><font size=-1>size=1000 bytes</font></tt>
<br><tt><font size=-1>dirs=43</font></tt></td>
<td BGCOLOR="#FFCCFF" NOSAVE><tt>ReiserFS</tt>
<br><tt>f<font size=-1>iles=11616</font></tt>
<br><tt><font size=-1>size=1000 bytes</font></tt>
<br><tt><font size=-1>dirs=43</font></tt></td>
</tr>
<tr>
<td><tt>Create</tt></td>
<td>30.68</td>
<td>57.94</td>
<td>36.38</td>
</tr>
<tr>
<td><tt>Fragm.</tt></td>
<td>1.38</td>
<td>1.01</td>
<td>1.03</td>
</tr>
<tr>
<td><tt>Copy</tt></td>
<td>75.21</td>
<td>149.49</td>
<td>84.02</td>
</tr>
<tr>
<td><tt>Fragm.</tt></td>
<td>1.38</td>
<td>1.01</td>
<td>1.43</td>
</tr>
<tr>
<td><tt>Slinks</tt></td>
<td>16.68</td>
<td>29.59</td>
<td>19.29</td>
</tr>
<tr>
<td><tt>Read</tt></td>
<td>225.74</td>
<td>348.99</td>
<td>409.45</td>
</tr>
<tr>
<td><tt>Stats</tt></td>
<td>25.60</td>
<td>46.41</td>
<td>89.23</td>
</tr>
<tr>
<td><tt>Rename</tt></td>
<td>16.11</td>
<td>33.57</td>
<td>20.69</td>
</tr>
<tr>
<td><tt>Delete</tt></td>
<td>6.04</td>
<td>64.90</td>
<td>18.21</td>
</tr>
</table>
<p>
<table BORDER NOSAVE >
<tr ALIGN=LEFT VALIGN=TOP NOSAVE>
<td NOSAVE><tt></tt>
<br></td>
<td BGCOLOR="#FFCCFF" NOSAVE><tt>ext3</tt>
<br><tt><font size=-1>files=2274</font></tt>
<br><tt><font size=-1>size=10000 bytes</font></tt>
<br><tt><font size=-1>dirs=32</font></tt></td>
<td BGCOLOR="#FFCCFF" NOSAVE><tt>XFS</tt>
<br><tt><font size=-1>files=2292</font></tt>
<br><tt><font size=-1>size=10000 bytes</font></tt>
<br><tt><font size=-1>dirs=31</font></tt></td>
<td BGCOLOR="#FFCCFF" NOSAVE><tt>reiserFS</tt>
<br><tt><font size=-1>files=2292</font></tt>
<br><tt><font size=-1>size=10000 bytes</font></tt>
<br><tt><font size=-1>dirs=31</font></tt></td>
</tr>
<tr>
<td><tt>Create</tt></td>
<td>27.13</td>
<td>25.99</td>
<td>22.27</td>
</tr>
<tr>
<td><tt>Fragm.</tt></td>
<td>1.44</td>
<td>1.02</td>
<td>1.05</td>
</tr>
<tr>
<td><tt>Copy</tt></td>
<td>55.27</td>
<td>55.73</td>
<td>43.24</td>
</tr>
<tr>
<td><tt>Fragm.</tt></td>
<td>1.44</td>
<td>1.02</td>
<td>1.12</td>
</tr>
<tr>
<td><tt>Slinks</tt></td>
<td>1.33</td>
<td>2.51</td>
<td>1.43</td>
</tr>
<tr>
<td><tt>Read</tt></td>
<td>40.51</td>
<td>50.20</td>
<td>56.34</td>
</tr>
<tr>
<td><tt>Stats</tt></td>
<td>2.34</td>
<td>1.99</td>
<td>3.52</td>
</tr>
<tr>
<td><tt>Rename</tt></td>
<td>0.99</td>
<td>1.10</td>
<td>1.25</td>
</tr>
<tr>
<td><tt>Delete</tt></td>
<td>3.40</td>
<td>8.99</td>
<td>1.84</td>
</tr>
</table>
<p>
From these tables you can see that ext3 is usually faster in Stats
Delate and Rename, while reiserFS wins in Create and Copy. Also note
that the performance of reiserFS in better in the first case (small
files) as expected by its technical documentation.
<h1 align=center>Conclusions</h1>
There are at present time at least two robust and reliable journalling
filesystems for Linux (i.e. XFS and reiserFS) which can be utilized
without fear.<br>
ext3 is still an alpha release and can undergo several failures. I had
some
problems using bonnie++ on this filesystem: the system reported some
VM
errors and killed the shell I was using. <p>
Considering the benchmark results my advice is to install a reiserFS
filesystem in the future (I'll surely do it).
<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Matteo Dell'Omodarme</H4>
<CITE>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>.
</CITE>
<!-- *** END bio *** -->
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2001, Matteo Dell'Omodarme.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 68 of <i>Linux Gazette</i>, July 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">Compiling and Installing a Linux Kernel</font></H1>
<H4>By <a href="mailto:auspicious_blessingsindia@hotmail.com">Subhasish Ghosh</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<h4><strong>Abstract:</strong></h4>
<p>Hi everyone, this article provides you with an extremely
detailed and step-by-step process describing how to Compile,
Configure and then Install a Customized Red Hat Linux Kernel. As
we all know, a Customized Kernel is required for many reasons,
and I wouldn't want to go into the details of those. I will only
show how to Compile, Configure and Install a Custom Kernel.
Though the steps mentioned below are primarily targeted for the
Red Hat Linux users, but the same process applies to the users of
other Linux Distributions also, of course, with a few minor
modifications as required. (For instance, not all systems use
initrd.)</p>
<h4><strong>Main:</strong></h4>
<p>Please note that I have performed all the steps mentioned
below on a computer system with the following configurations:
Compaq Presario 4010 Series computer system, 15.5 GB Hard Disk
Space, 96 MB RAM, 400 MHz Intel Celeron Processor, Red Hat Linux
7.0 Distribution Release. Underlying Kernel: <strong>2.2.16-22</strong></p>
<h4><strong>Aim:</strong></h4>
<p>Our aim would be to obtain a fully working <strong>Customized
Kernel</strong> after all the steps mentioned below have been
completed, for example, I have a Customized Kernel named
&quot;2.2.16-22ghosh&quot; running on my system (cause my name is
Subhasish Ghosh, you could have anything else, in fact a couple
of them running together!). So, happy hunting and compiling the
Linux Kernel.</p>
<h4><strong>Steps to Compile, Configure and Install a Customized
Red Hat Linux Kernel:</strong></h4>
<p>The steps to be followed are as follows:</p>
<p>Step 1: Login as &quot;<strong>root</strong>&quot; and then
perform these steps.</p>
<p>Step 2: At the command prompt, type in: &quot;<strong>rpm -q
kernel-headers kernel-source make dev86</strong>&quot;</p>
<p>Step 3: If these RPMs are already installed, then proceed to
step 4. Otherwise, mount the Red Hat Linux 7.0 CD-ROM and then
perform a rpm -Uvh for installing these RPMs.</p>
<p>Step 4: If you have a fully working X Window System, then type
in &quot;<strong>startx</strong>&quot; at the command-prompt. In
case you don't have an X Window System configured, I personally
would suggest you to have it done before proceeding cause it
would be extremely beneficial. If X Window System is NOT
configured, then type in &quot;make config&quot; or &quot;make
menuconfig&quot; at the command-prompt. Please note that I have
assumed that you have an X Window System running on your system,
and for that reason, just type in &quot;startx&quot;. </p>
<p>Step 5: Then once within the GNOME environment, open the GNOME
Terminal and type in: &quot;<strong>cd /usr/src/linux</strong>&quot;
and press enter.</p>
<p>Step 6: Then from within /usr/src/linux, type in &quot;<strong>make
xconfig</strong>&quot;. </p>
<p>Step 7: The GUI version of &quot;make config&quot; would come
up on the screen. It provides you with various options that you
have for obtaining a Customized Kernel.</p>
<p>Step 8: Now, I would suggest you to leave most of the default
options just as it is. Just don't try to fiddle around cause most
of the options are sensitive and requires expert handling. Just
make sure you make the following changes: </p>
<p>1.<strong><u>Processor Type and Features</u></strong>: Choose
the correct Processor depending on whether you are working on a
Pentium 2, 3, or Intel Celeron like me. For example, I did the
following: Processor Family: PPro/686MX, Maximum Physical Memory:
1 GB, Math Emulation: Yes, MTRR: Yes, SMP: Yes.</p>
<p>2.Open the <strong><u>Filesystems</u></strong> dialog and then
make the following changes to it: For example I did: DOS FAT fs
support: Yes(y), MSDOS fs support: Yes(y), UMSDOS: m,
VFAT(Windows 95) support: Yes(y), NTFS filesystem support
(read-only): Yes(y), NTFS read-write support(DANGEROUS): No(n).
After you have made these changes, please make sure you haven't
changed the others in the process. All these above-mentioned
changes are quite harmless and won't cause any harm to your
existing Linux Kernel. </p>
<p>3.Save and Exit from the Main dialog. </p>
<p>Step 9: Then, perform a &quot;<strong>ls -al</strong>&quot;
from within the path: /usr/src/linux.</p>
<p>Step 10: I am sure you can see a file called: &quot;<strong>Makefile</strong>&quot;.
It is an extremely important file for this entire Compilation
process. So, make sure you create a backup of this file, by
using: &quot;<strong>cp Makefile Makefile.bak</strong>&quot;</p>
<p>Step 11: Now, do: (from within /usr/src/linux) &quot;<strong>vi
Makefile</strong>&quot;.</p>
<p>Step 12: Go to line <strong>EXTRAVERSION</strong> and change
it to something like this, for example I changed
EXTRAVERSION=-22, to EXTRAVERSION=&quot;-22ghosh&quot;. You are
free to name it anyway you wish. </p>
<p>Step 13: Save and exit the file.</p>
<p>Step 14: All the following steps should be done from within:
/usr/src/linux. Type in: &quot;<strong>make dep clean</strong>&quot;,
and press enter.</p>
<p>Step 15: Then type in: &quot;<strong>make bzImage modules</strong>&quot;.
This would take some time, go and have a drink while it compiles
all the necessary files. I usually take a nap during this time,
cause I do all this stuff in the middle of the night.</p>
<p>Step 16: After this step is over, a &quot;<strong>bzImage</strong>&quot;
file would be created in the directory
/usr/src/linux/arch/i386/boot, just go to this directory and
check whether a file called &quot;bzImage&quot; has been produced
or not. IF AND ONLY IF all the compilation steps have been
executed correctly and all the options that we have had chosen in
&quot;make xconfig&quot; are correct, this file would be
produced. If you can find this file, which I am sure you would,
well, you can start enjoying already, cause you have won 75% of
the battle. If you can't see this file, I am sorry, but you must
have had made a mistake somewhere, just take a break and carry
out all the steps again from the start. I am sure you would
succeed.</p>
<p>Step 17: Type in (from within /usr/src/linux): &quot;<strong>cp
./arch/i386/boot/bzImage /boot/vmlinuz-2.2.16-22ghosh</strong>&quot;
and press enter.</p>
<p>Step 18: Then type in: &quot;<strong>cp System.map
/boot/System.map-2.2.16-22ghosh</strong>&quot;</p>
<p>Step 19: Then type in: &quot;<strong>make modules_install</strong>&quot;
and press enter. You would see all the modules being installed in
a new customized directory. </p>
<p>Step 20: Then type in: &quot;<strong>mkinitrd
/boot/initrd-2.2.16-22ghosh.img 2.2.16-22ghosh</strong>&quot;</p>
<p>Step 21: Then, type in: &quot;<strong>vi /etc/lilo.conf</strong>&quot;
and then add the following entry: </p>
<p><strong>image=/boot/vmlinuz-2.2.16-22ghosh </strong></p>
<blockquote>
<p><strong>label=GhoshKernel<br>
initrd=/boot/initrd-2.2.16-22ghosh.img<br>
root=/dev/hdc5<br>
read-only</strong></p>
</blockquote>
<p>Step 22: Save and exit. Please note that you can change the
entries in the lilo.conf file as you desire, and the root should
be the root in your system, in my machine, it's at /dev/hdc5. So,
insert the info from your own system.</p>
<p>Step 23: Type in: &quot;<strong>/sbin/lilo -v -v</strong>&quot;</p>
<p>Step 24: Read all the info on the screen. If there are no
errors, well, the job's all done. Congratulations!!!!</p>
<p>Step 25: Reboot the system by typing in: &quot;<strong>/sbin/reboot</strong>&quot;
or &quot;<strong>/sbin/shutdown -r now</strong>&quot;.</p>
<p>Step 26: In the start-up screen, press Tab (or Control-X, if
you have the LILO start-up screen), and you can see the entry:
&quot;GhoshKernel&quot; along with the other pre-existing
entries.</p>
<p>Step 27: Type in: <strong>GhoshKernel</strong> and press
enter. The fully working Customized Kernel will be seen booting
on your system. So, you have a fully working Customized Kernel
working on your system now. </p>
<h4><strong>Conclusion:</strong></h4>
<p>After logging in as &quot;root&quot;, type in: &quot;<strong>uname
-r</strong>&quot; and press Enter. You can see the following
entry on the screen: <strong><u>2.2.16-22ghosh</u></strong> that
proves that you are running a Customized Kernel, and not <strong>2.2.16-22</strong>
which was the Kernel we had started out with. That's all. Also
remember, that you can have as many number of Kernel versions as
you like running on a single computer system. In case this
doesn't work out or you guys (and gals) face problems, make sure
you do e-mail me at <a
href="mailto:auspicious_blessingsindia@hotmail.com">auspicious_blessingsindia@hotmail.com</a>
for questions and suggestions. I would really like to hear from
you and help you and I hope this detailed HowTo helps everyone
out there who wants to run a fully working Customized Kernel.</p>
<h4><strong>Resources:</strong></h4>
<p>There exists a lot of info on how to configure and run fully
Optimized and Customized Kernels at a number of web-sites. Make
sure you check out: <a href="http://www.vmlinuz.nu">http://www.vmlinuz.nu</a>
and a few other ones for the HowTo's and Documentation on Linux
Kernel. </p>
<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Subhasish Ghosh</H4>
<CITE>I'm 20 years old, and
currently living in India. I am a computer-systems engineering
student as well as a Computer Professional. I currently hold 6
Microsoft Certified Professional(MCP) Certifications, and also am
a Microsoft Certified Professional Certified on NT 4.0 Track. I
have been working with Linux for a long time, especially Red Hat
Linux. I am currently preparing for the Red Hat Linux Certified
Engineer(RHCE) certification Exam and plan to work primarily with
the Linux operating system in the future.</CITE>
<!-- *** END bio *** -->
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2001, Subhasish Ghosh.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 68 of <i>Linux Gazette</i>, July 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">A Linux Client for the Brother Internet Print Protocol</font></H1>
<H4>By <a href="mailto:grahjenk@au1.ibm.com">Graham Jenkins</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<h2>The Brother Internet Print Protocol</h2>
<p>A recent article <a href="../issue65/jenkins.html">
Internet Printing--Another Way</a> described a printing protocol which
can be used with some
<a href="http://www.brother.com">Brother</a> printers. It enables users
of Windows machines to send a multi-part base-64 encoded print file via
email directly to a Brother print server.</p>
<p>The article went on to show how the functionality of the Brother print
server can be implemented in simple Perl program which periodically polls
a POP3 server to check for jobs whose parts have all arrived. When such a
job is detected, its parts are downloaded in sequence and decoded for
printing.</p>
<h2>A Linux Client</h2>
<p>The Perl program mentioned above has been in use at my place for a few
months, and has made it a lot easier for me to print Word and other
Microsoft-format documents to a remote printer. But it hasn't made life
any easier for those at my place who use Linux workstations.</p>
<p>A brief search on the Brother website failed to reveal a Linux client,
so it was decided that I should develop one. The result is described
hereunder.</p>
<h2>Implementation</h2>
<p>Conventional wisdom probably dictates that a program which breaks a binary
input stream into chunks for feeding into a decoder in sequence - should be
implemented in Perl, or perhaps in C. In fact, the common Bourne shell and
its derivatives have all the necessary capabilities when used with a couple
of general Unix/Linux tools like 'split' and 'wc'.</p>
<h2>Program Walk-Through</h2>
<p>As shown in the listing
(<a href="misc/jenkins/BIPclient.sh.txt">text version</a>),
the program starts by checking that it has been
called with two arguments; a usage message is printed if this is not the
case. It then defines a function which will be called later to print
a header on each part as it is sent. In particular, this function will
include an address for notification, a part number, a part count, and
a job identifier.</p>
<p>The program body begins by generating an email address for the originator,
together with a timestamp. These are concatenated and used to generate a
name for a scratch directory. A trap is set to remove any directory having
that name in the event of error, and an attempt is made to create the scratch
directory.</p>
<p>The Unix/Linux 'split' utility is then used to split the program input
into parts whose size is given by the first program argument. Each of these
is fed into a base-64 encoder and mailer (with appropriate pre-amble) to
the address given by the second program argument.</p>
<p>The program ends by removing the scratch directory and returning
an exit status.</p>
<pre>
#!/bin/sh
# BIPclient.sh Brother Internet Print client program. Breaks incoming stream
# into parts of designated size, then does base-64 encoding of
# each part and emails it with appropriate preamble etc. to
# designated email address. Graham Jenkins, IBM GSA, June 2001.
[ $# -ne 2 ] &amp;&amp; echo "Usage: `basename $0` kb-per-part destination"&gt;&amp;2 &amp;&amp;
echo " e.g.: man a2ps | a2ps -o - | `basename $0` 16 lp3@acme.com"&gt;&amp;2&amp;&amp; exit 2
do_header () { # Function to print header
cat &lt;&lt;EOF
START-BROBROBRO-START
BRO-SERVICE=ZYXWVUTSRQ980
BRO-NOTIFY=Always
BRO-REPLY=$Me
BRO-PARTIAL=$Part/$Total
BRO-UID=$Me$Now
STOP-BROBROBRO-STOP
Content-Type: application/octet-stream; name="PrintJob.PRN"
Content-Transfer-Encoding: base64
EOF
}
Me=`whoami`@`hostname`
[ -n "`domainname`" ] &amp;&amp; [ "`domainname`" != "(none)" ] &amp;&amp; Me=$Me.`domainname`
Now=`date '+%Y%m%d%H%M%S'` # Generate email address,
Dir=/tmp/`basename $0`.$Me$Now # timestamp and directory name
trap 'rm -rf $Dir;echo Oops&gt;&amp;2;exit 1' 1 2 3 15 # Set cleanup trap
mkdir $Dir || exit 1 # Create directory
split -b ${1}k - $Dir/ || exit 1 # Generate parts
Total=`ls $Dir|wc -w |tr -d ' '`|| exit 1 # Count parts
Part=0
for File in `ls $Dir/*` ; do # Encode and send parts
Part=`expr 1 + $Part`
[ -t 2 ] &amp;&amp; echo "Sending part: $Part/"$Total" to: $2 .. $Now" &gt;&amp;2
( do_header
base64 $File # Use mmencode or base64
echo ) | Mail -s "Brother Internet Print Job" $2
done
rm -rf $Dir # Cleanup and exit
exit 0
</pre>
<h2>Limitations</h2>
<p>In the interests of simplicity, the 'do_header' function shown in
the listing leaves out some of the header lines which
are generated by the Windows client programs,
and uses a dummy value for 'BRO-SERVICE'. In consequence, it may not
work satisfactorily with a genuine Brother print server. If any readers
have such a device, I would be interested in their feedback.<p>
<p>The 'unique' message identifier can actually be duplicated if a user
submits two jobs within the same one-second period; this is a limitation of
the Brother identifier format. An alternative identifier format which inserts
a process number before the user's email address could be used if required.</p>
<p>And finally, the creation of a scratch directory to hold what is
effectively a duplicate of the raw print file - may be seen as a problem
if the client machine has a limited amount of temporary file-space. The
issue here is that we really have to take a copy of the raw print file
as it arrives so that we can generate a "total-parts" figure for
inclusion in the header of each mailed component.</P>
<p>It is possible (using Perl or 'dd') to generate and mail parts on the
fly, without using any temporary files - provided that the server program
is modified slightly so as not to require a "total-parts" figure in
the header of each part. I will be happy to send details to anyone who
would like to do it this way.</p>
<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Graham Jenkins</H4>
<CITE>Graham is a Unix Specialist at IBM Global Services, Australia. He lives
in Melbourne and has
built and managed many flavors of proprietary and open systems on several
hardware platforms.</CITE>
<!-- *** END bio *** -->
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2001, Graham Jenkins.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 68 of <i>Linux Gazette</i>, July 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 Opening of the Field: PostgreSQL's Multi-Version Concurrency Control</font></H1>
<H4>By <a href="mailto:jmitchell@greatbridge.com">Joseph Mitchell</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<ALIGN=CENTER>
<H2><I>PostgreSQL's Multi-Version Concurrency Control feature
frees data tables for simultaneous use by readers and writers.</I></H2>
</CENTER>
<p>
<ALIGN=LEFT>
<h3>Introduction</h3>
<p>
Question of the day: what's the single most annoying thing about most large multi-user databases? As anyone who's worked with one knows, it's waiting. And waiting. Whether the database system is using table-level, page-level, column-level, or row-level locking, the same annoying problem persists: readers (SELECTs) wait for writers (UPDATEs) to finish, and writers (UPDATEs) wait for readers (SELECTs) to finish. If I could only find a
database that doesn't require locking. Will it ever be? Well, the answer is yes".
<P>
<h3>PostgreSQL's no-locking feature</h3>
For PostgreSQL , "no-locking" is already a reality. Readers never wait for writers, and writers never wait for readers. I can already hear the objections to the claim that there is no "no-locking" in PostgreSQL, so let me explain PostgreSQL's advanced technique called Multi-Version Concurrency Control (MVCC).
<P>
<h3>MVCC</h3>
<P>
In other database systems, locks are the only mechanism used to maintain concurrency control and data consistency. PostgreSQL, however, uses a multi-version model instead of locks. In PostgreSQL, a version is like a snapshot of the data at a distinct point in time. The current version of the data appears whenever users query a table. Naturally, a new version appears if they run the same query again on the table and any data has changed. Such changes happen in a database through UPDATE, INSERT, or DELETE statements.
<P>
<h3>Example: Row locking vs. MVCC</h3>
<P>
The essential difference between traditional row-level locking and PostgreSQL's MVCC lies in when users can see the data they selected from a particular table. In traditional row-level locking, users may wait to see the data, whereas PostgreSQL's MVCC ensures that users NEVER wait to see the data. Let's look at the following example to illustrate more clearly.
<P>
<PRE>
SELECT <I>headlines</I> FROM <I>news_items</I>
</PRE>
<p>
In this example, the statement reads data from a table called news_items and displays all the rows in the column called headlines. In data systems that use row-level locking, the SELECT statement will block and the user will have to wait if another user is concurrently inserting (INSERT) or updating (UPDATE) data in the table news items. The transaction that modifies the data holds a lock on the row(s) and therefore all rows from the table cannot be displayed, forcing users to wait until the lock releases. Users who have encountered frequent locks when trying to read data know all too well the frustration this locking scheme can cause.
<P>
In contrast, PostgreSQL would allow all users to view the news_items table concurrently, eliminating the need to wait for a lock to be released. This is always the case, even if multiple users are inserting and updating data in the table at the same time. When a user issues the SELECT query, PostgreSQL displays a snapshot - a version, actually - of all the data that users have committed before the query began. Any data updates or inserts that are part of open transactions or that were committed after the query began will not be displayed. Makes a lot of sense, doesn't it?
<P>
<h3>A Deeper Look at MVCC</h3>
<P>
Database systems that use row-level locking do not retain old versions of the data, hence the need for locks to maintain data consistency. But a deeper look into how "no-locking" through MVCC works in PostgreSQL reveals how PostrgreSQL gets around this limitation. Each row in PostgreSQL has two transaction IDs. It has a creation transaction ID for the transaction that created the row, and an expiration transaction ID for the transaction that expired the row. When someone performs an UPDATE, PostgreSQL creates a new row and expires the old one. It's the same row, but in different versions. Unlike database systems that don't hold on to the old version, when PostgreSQL creates a new version of the row it also retains the old or expired version. (Note: Old versions are retained until a process called VACUUM is run on the database.)
<P>
That's how PostgreSQL creates versions of the data, but how does it know which version to display? It bases its display on several criteria. At the start of a query, PostgreSQL records two things: 1) the current transaction ID and 2) all in-process transaction IDs. When someone accesses data, Postgres issues a query to display all the row versions that match the following criteria: the row's creation transaction ID is a committed transaction and is less than the current transaction counter, and the row lacks an expiration transaction ID or its expiration transaction ID was in process at query start.
<P>
And this is where MVCC's power resides. It enables PostgreSQL to keep track of transaction IDs to determine the version of the data, and thereby avoid having to issue any locks. It's a very logical and efficient way of handling transactions. New PostgreSQL users are often pleasantly surprise by the performance boost of MVCC over row-level locking, especially in a large multi-user environment.
<P>
MVCC also offers another advantage: hot backups. Many other databases require users to shutdown the database or lock all tables to get a consistent snapshot - not so with PostgreSQL. MVCC allows PostgreSQL to make a full database backup while the database is live. It simply takes a snapshot of the entire database at a point in time and dumps the output even while data is being inserted, updated or deleted.
<P>
<h3>CONCLUSION</h3>
<P>
MVCC ensures that readers never wait for writers and writers never wait for readers. It is a logical and efficient version management mechanism that delivers better database performance than traditional row-level locking.
<P>
<i>PostgreSQL is available for download at the Great Bridge Web site
(<A HREF="http://www.greatbridge.com/download">www.greatbridge.com/download</A>).</i>
<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Joseph Mitchell</H4>
<CITE>Joseph is a knowledge engineer for Great Bridge LLC, a company formed to
promote, market and provide professional support services for PostgreSQL, the
open source database, and other open source business solutions. He can be
reached at <A
HREF="mailto:jmitchell@greatbridge.com">jmitchell@greatbridge.com</A>.</CITE>
<!-- *** END bio *** -->
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2001, Joseph Mitchell.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 68 of <i>Linux Gazette</i>, July 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">Using RPM: The Basics (Part I)</font></H1>
<H4>By <a href="mailto:jose@cwru.edu">Jose Nazario</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
This documentation is designed to serve as a brief introduction to the
Red Hat Package Management system, or RPM. Part 1 will cover installation
of RPM packages, while part 2 will cover building your own RPM packages
for distribution. We will cover what RPM is, why you would want to use it,
compare it to other packaging systems on Linux and UNIX, and how to get
it. The bulk of the time will be spent on how to use RPM for installing,
checking packages, and removal of installed packages. Neither section will
cover the RPM API.
<h2> What is RPM?</h2>
The Red Hat Package Manager (RPM) is a toolset used to build and manage
software packages on UNIX systems. Distributed with the Red Hat Linux
distribution and its derivatives, RPM also works on any UNIX as it is open
source. However, finding RPM packages for other forms of UNIX, such as Solaris
or IRIX, may prove difficult.
<p>Package management is rather simple in its principles, though it can be
tricky in its implementations. Briefly, it means the managed installation
of software, managing installed software, and the removal of software
packages from a system in a simplified manner. RPM arose out of the needs
to do this effectively, and no other meaningful solution was available.
<p>RPM uses a proprietary file format, unlike some other UNIX software
package managers. This can be problematic if you find yourself needing to
extract one component from the package and you don't have the RPM utility
handy. Luckily a tool like Alien exists to convert from RPM to other
formats. It can be possible, through tools like Alien, to get to a file
format you can manage using, say, tar or ar.
<p>The naming scheme of RPM files is itself a standardized convention.
RPMs have the format (name)-(version)-(build).(platform).rpm. For example,
the name cat-2.4-7.i386.rpm would mean an RPM for the utility "cat"
version 2.4, build 7 for the x86. When the platform name is replaced by
"src", it's a source RPM.
<h2> Why Package Management?</h2>
At first glance you may say to yourself, "I can manage this myself. It's
not that many components ..." In fact, for something as small as, say,
cat, which has one executable and one man page, this may be so. But
consider, say, KDE, which has a mountain of components, dependencies, and
likes to stick them everywhere. Keeping track of it all would be tough, if
not impossible.
<p>Package management makes it all easier. By letting a program maintain
the information about the binaries, their configuration files, and
everything else about them, you can identify which ones are installed,
remove them easily or upgrade them readily, as well.
<p>Installation becomes a snap. You select what you want, and ask the
system to take care of the dirty work for you. Unpack the program, ensure
that there is space, place things in the right order, and set them up for
you. It's great, it's like having a valet take care of your car when you
go to a restaraunt. Dependencies, or additional requirements for a
software package, are also managed seamlessly by a good package manager.
<p>Management of installed packages is also greatly facilitated by a good
package management system. It keeps a full list of software installed,
which is useful to see if you have something installed. More importantly,
it makes upgrading a breeze. Lastly, this makes verification of a software
package quite easy to do. By knowing what packages are installed, and what
the properties of the components are, you can quickly diagnose a problem
and hopefully fix it quickly.
<h2> How Does RPM Compare to Other UNIX Package Systems?</h2>
I have had the (mis)fortune of working with many UNIX variants, and
gaining some experience with their package formats. While I sometimes slag
RPMs, in comparison to other UNIX software packaging formats I find it
usually comes out on top for my needs. Here's a brief rundown on the pro's
and cons of some of the other formats and tools:
<br>&nbsp;
<table> <tr> <td><b>Format</b></td>
<td><b>Platform</b></td>
<td><b>Pro</b></td>
<td><b>Con</b></td> </tr>
<tr> <td>inst</td>
<td>IRIX(SGI)</td>
<td>great graphical installer</td>
<td>amazingly slow, frequentl reboots after, no network installs (aside
from NFS)</td> </tr>
<tr> <td>sw</td>
<td>HPUX(HP)</td>
<td>(are there any?), also supports net installs</td>
<td>terribly slow</td> </tr>
<tr> <td>pkg</td>
<td>BSD(many)&nbsp;</td>
<td>tarballs, net installs</td>
<td>lack signatures, sums</td> </tr>
<tr> <td>?</td>
<td>Solaris(SUN)</td>
<td>(are there any?)&nbsp;</td>
<td>slow, lack signatures, sums</td> </tr>
<tr> <td>.deb</td>
<td>Debian</td>
<td>just ar's, easy to extract w/o tool&nbsp;</td>
<td>lacks signatures</td> </tr> </table>
<p>In brief, my biggest complaint about RPM is the lack of a solid GUI
interface to it. While a few exist (like gnorpm and glint), they lack the
more complex features that SGI's Software Manager has. Overall, I find
that RPM has better conflict handling and resolution than inst does, and
is much, much faster. Hence, i'm willing to live without a strong GUI.
<p>My biggest raves for RPM, however, are in speed and package checking,
using both package signatures and the sums of the components. As an
example, once I had to reboot an SGI just because I reinstalled the
default GUI text editor (aka jot). It also took approximately 15 minutes
to reinstall that small package, before the reboot.
<h2> RPM In a Nutshell</h2>
Much like a compressed tarball, RPM uses a combination of rolling together
multiple files into one archive and compression of this archive to build
the bulk of the RPM package. Furthermore, additional header information is
inserted. This includes pre- and post-installation scripts to prepare the
system for the new package, as well as information for the database that
RPM maintains. Dependencies are checked before any installation occurs,
and if the appropriate flags are set for the installation they are also
installed.
<p>It is this database that makes RPM work the magic that it does. Stored
in there are all of the properties of the installed packages. Should this
become corrupted, it can be rebuilt using the rpm tool.
<h2> The Hows of RPM</h2>
We will now focus on the three core actions of RPM discussed in this
documentation. They include installation of new packages, management of
installed packages, and package removal. We will begin at the beginning,
and how to add a package using RPM.
<h3> Installation Using RPM</h3>
This is the most basic RPM function, and one of the most popular: the
installation of new software packages using RPM. To do this, give rpm the
-i flag and point it to an RPM:
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -i (package)
<p>This will install the package if all goes well and send you back to a
command prompt without any messages. Pretty boring, and worse if you want
to know what happened you're out of luck. Use the -v flag to turn on some
verbosity:
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -iv (package)
<p>All that gets printed out is the package name, but no statistics on the
progress or what it did. You can get a hash marked output of the progress
is you use the -h flag. People seem to like using -ivh together to get a
"pretty" output:
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -ivh (package)
<p>Again, this doesn't tell you much about what just happened, only that
it hopefully did. Hence, I usually crank up the verbosity (-vv) when I
install. This lets me see what's going on:
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -ivv (package)
<p>While the output usually scrolls, I can see exactly what happened and
if any problems were encountered. Plus I get to see where stuff was
installed.
<p>Dependencies are handled pretty wisely by RPM, but this itself depends
on a good package builder in the first place. I have seen packages that
depend upon themselves, for instance, and some that seem to depend on
packages that will break other things. Keep this in mind.
<p>Sometimes RPM will whine about a dependency which is installed but
isn't registered. Perhaps you installed it not using an RPM for the
package (ie OpenSSL). To get around this, you can force it to ignore
dependencies:
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -ivv --nodeps (package)
<p>Note that this isn't always wise and should only be done when you know
what you are getting youself into. This will rarely break installed stuff,
but may mean the installed package wont work properly.
<p>On rare occassion RPM will mess up and insist that you have a package
installed when you don't. While this is usually a sign that something is
amiss, it can be worked around. Just force the installation:
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -ivv --force (package)
<p>Beware. Just like when you ignored the dependencies, forcing a package
to install may not be wise. Bear in mind that your machine could burst
into flames or simply stop working. Caveat emptor and all that.
<p>This probably wins the award for one of the coolest features in RPM:
network installations. Sometimes, you don't have network clients on a
system but you need to install them via RPM. RPM has built in FTP and web
client sowftare to handle this:
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -iv <a
href="ftp://ftp.redhat.com/path/package.rpm">ftp://ftp.redhat.com/path/package.rpm</a>
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -iv <a
href="http://www.me.com/path/package.rpm">http://www.me.com/path/package.rpm</a>
<p>I don't think it can do SSL HTTP connections, though. Debian's packages
can do this, as can BSD packages. I don't think most commercial tools can
do this, though.
<h3> Managing Your Packages</h3>
OK, you know how to install packages. But let's say you want to work with
some packages before you, either installed or not. How can you do this?
Well, simply put, you can use package management features in rpm to deal
with packages, ones that are installed already or ones that are not, to
look inside of them. This can include verifying packages, too.
<p>When you get a new package, you may want to examine it to see what it
offers. Using query mode, you can peek inside. To simply query a package
and get some generic information about it, just simply:
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -qp (package)
<p>This should bring just the name of the package. Pretty boring, isnt it?
A much more useful method is to get the package information from the
package itself:
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -qip (package)
<p>This will bring up the author, build host and date, whether it's installed
yet, etc, about a package. Also included is a summary about the package's
functionality and features.
<p>All of this is nice, but let's say you want to see what is really
inside the package, what files are inside of it? Well, you can list the
contents of a package, much like you would get the table of contents of a
tar archive (using tar -tvf):
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -qlp (package)
<p>This will list all of the files within the archive, using their full
pathnames. I use this often to see what will be installed with a package,
but most importantly where. I like to stick to conventions about putting
stuff in their expected places, but some packagers do not. Lastly, to show
all of the packages you have installed on your system, use:
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -qa
<p>This will bring up a list of packages installed on the current system.
It may be useful to sort them (by piping through sort, rpm -qa | sort).
Use these names when uninstalling packages (below).
<p>One of my favorite things about RPM is how it can verify packages. This
is useful in detecting a compromised machine, or a binary that may be
missing or modified due to some error on your part. To verify one package,
just point rpm at it with the -V flag:
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -V (package)
<p>This should bring up a brief description of wether or not the package
checks out. To verify all packages installed on a system, it is quite
simply:
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -Va
<p>Verify mode brings up several statistics about a file. Their shorthand
is as follows:
<br>&nbsp; <table> <tr> <td>5</td>
<td>MD5 sum</td> </tr>
<tr> <td>S</td>
<td>File size</td> </tr>
<tr> <td>L</td>
<td>Symlink</td> </tr>
<tr> <td>T</td>
<td>Mtime (modification time)</td> </tr>
<tr> <td>D</td>
<td>Device</td> </tr>
<tr> <td>U</td>
<td>User</td> </tr>
<tr> <td>G</td>
<td>Group</td> </tr>
<tr> <td>M</td>
<td>Mode (includes permissions and file type)</td> </tr> </table>
<p>Sometimes they're meaningless, for example if you modify your
/etc/inetd.conf file it will show up as a different size and MD5 sum.
However, some things shouldn't change, like /bin/login. Hence, rpm -Va can
be a useful quick security check, suggesting which things need more
peering into.
<p>One of the great things about package management we stated at the
outset was the ease with which upgrading can be performed. RPM has two
sometimes confusing options to upgrading packages. The first is a simple
upgrade:
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -U (package)
<p>What is confusing about it is it's resulting action if the package is
not yet installed. If it finds it, the package is upgraded. If it doesn't
find it, you are upgraded to it, meaning the package is installed. This
can be scary sometimes if you don't mean to install a package and an
update comes out, which you blindly follow. Because of this, I suggest
using "freshen" on packages you only want to ensure you have the latest
version of:
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -F (package)
<p>This will only update installed packages, and not install the package
if it is missing.
<p>Upgrades are done in an interesting fashion, too. The new version is first
installed and the differences with the old version are noted. Then the
older version is removed, but only the unique portions of it so as not to
remove the new portions. Imagine if /usr/local/bin/netscape were upgraded
and then removed, that would defeat the whole effort!
<h3> Uninstalling an RPM</h3>
You can install, upgrade, and manage, and hence you can definitely
uninstall using RPM. The flag to use is -e, and many of the same
conditions for installation apply for removal. To silently uninstall an
RPM package, use:
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -e (package)
<p>Note that, unlike for installations and upgrades, package here refers
not to package-version.i386.rpm, but instead to package-version. These are
the values reported in query mode, so use those. You should be able to get
all components of a package for removal by specifying the most generic,
common part of the name, ie for linuxconf and linuxconf-devel, specify
linuxconf. Dependencies can also be avoided:
<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; rpm -e --nodeps (package)
<p>The same caveats apply here, as well, you could wind up breaking more
stuff than you anticipated. Verbosity flags can also be added, just like
in installations.
<h3> Some Notes about RPMs</h3>
Sometimes maintainers build rather stupid dependencies for their RPMs.
Case in point, libsafe. It has a wierd dependency: itself. As such, I
usually find I have to install --nodeps to get it to install properly.
Other times a package will contain extra junk, and you could wind up
installing more than you had planned for.
<p>My biggest complaint are RPMs that have a name that doesn't suit the
function of the pieces. While this can be gotten around by digging around
using the query tools as described above, it's more time than I care to
waste. Name your RPMs well, I suggest.
<h3> Getting RPM</h3>
You can get RPM for any Linux or UNIX variant, as it is Open Source. RPM
comes native in Red Hat Linux, and some derivatives. Versions 3.0 and above
are recomended for compatability, some stupid stuff went on before that
that 3.0 hopes to fix. Version 4.0 reportedly has a different database
format, and so I reccomend checking around for how to get around this
issue before you upgrade to 4.0. I'm not sure if can simply rebuild the
database in 4.0 to remedy this.
<p>RPM is normally distributed as an RPM of itself. Cute, eh? Luckily, it
also comes in a gzipped tarball and also in source form. I have RPM
installed on Slackware, for example, and could install it on IRIX or
Solaris if I so desired. It's nearly useless on non-Linux platforms as
rarely are packages built in RPM for other UNIX variants.
<h3> Coming Next Time</h3>
In the upcoming second half of this documentation we will taking a look at
how to build an RPM for yourself. We'll look at the spec files, layout in
/usr/src and the building flags. It's pretty easy once you learn a few
basics.
<h3> Resources</h3>
The best place to start is the online website for RPM, <a
href="http://www.rpm.org/">http://www.rpm.org/</a>. There you will find
the book 'Maximum RPM', which covers how to use, build, and even
programming with the RPM API. The RPM help page (rpm -h) is also quite
useful once you learn a few basics. To find RPM archives, check <a
href="http://www.rpmfind.net/">http://www.rpmfind.net/</a>, which
maintains a great searchable database of packages for various
distributions and versions on a variety of platforms. Very useful.
<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Jose Nazario</H4>
Jos&eacute; is a Ph.D. student in the department of biochemistry at Case
Western Reserve University in Cleveland, OH. He has been using UNIX for
nearly ten years, and Linux since kernels 1.2.
<!-- *** END bio *** -->
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2001, Jose Nazario.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 68 of <i>Linux Gazette</i>, July 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">Chosing Good Passwords</font></H1>
<H4>By <a href="mailto:jose@cwru.edu">Jose Nazario</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<p>
Right now I'm running Crack on some people, and I'm doing a lot of
thinking about passwords and how to generate good ones. Specifically, what
sorts of things I can do to get better ones. I was recently asked by a
friend about any ideas on passwords and about sharing them at our local
event "LinuxDay". I'll take some time now and discuss passwords with you
now. Passwords provide our most major defense against unauthorized use of
our systems, so let's keep them good, even in the presence of crypto,
firewalls, and rabid dogs.
<p> OK, so this is how I generate passwords for myself: I reach over, grab
the nearest issue of <a href="http://www.nature.com/">"Nature"</a>, open
it up to a genetics article and point to some gene construct name and use
that. No lie. It's how I chose good passwords. Random, complex, easy to
generate. Granted, a lot of dictionaries have now included gene names, but
these are construct names, which differ from gene names. So, instead of
something like "Brc1" it's more like "pRSET5a::20STa::6xHis". You can
shove the latter in any cracking program and it will not fall out quickly,
I can almost garauntee it.
<p>
The trick is this: users dislike complex passwords. They're difficult to
remember, they'll cry. And they're right. To overcome that, they'll
either write it down on some post-it note on their monitor or change it to
something silly, like "LucyDoll".
<P>Most importanly, a password should roll off the fingers. It should be
typed quickly and efficiently, and of course corectly. For that matter, I
sometimes will type it ten times quickly to generate the rythm of it, and
that works.
<P>Quickly, a diversion to the Crack 5.0a documentation, this is ripped
from the appendix. It deals with password security and security in
general, and is some good wisdom:
<BLOCKQUOTE>
At the bottom line, the password "fred" is just as secure (random) as
the password "blurflpox"; the only problem is that "fred" is in a more
easily searched part of the "password space".
Both of these passwords are more easily found than "Dxk&amp;2+15^N"
however. Now you must ask yourself if you can cope with remembering
"Dxk&amp;2+15^N".
</BLOCKQUOTE>
<P>OK, great, we've chosen a good password... oh crap. We have about ten
accounts, some on BBS's, some on systems we can't ssh to, and
some are the root passwords on systems we administer for major businesses.
or we have to rotate them often. How do we keep track of them all?
<P>Myself, I do two things: I keep <em>levels</em> of passwords. I have a
handful of passwords for disposable things. Yeah, if someone grabs a
password of mine I use on a BBS and posts some flamebait, I will get some
flack. But honestly, I doubt anyone will do that, it's the systems I care
about and administer that I really protect. Hence, I cycle passwords
there, using very strong passwords that <strong>never</strong> go out on
the wire without some strong crypto behind them (ie secure shell). A new
password is chosen (randomly), and the old ones are bumped down the chain
to less demanding positions, system and accounts. I use the tricks I
outlined above, and it has paid off. Sometimes I forget them, and that's
always a scary moment, but it's usually no more than a minute or two.
<P>Keeping track of multiple passwords is easily handied using the
<A HREF="http://www.counterpane.com">Password Safe</A> from Counterpane
systems, but that only works on Windows systems. I once started writing
the implementation for Linux, but given my poor programming skills and
heavy load of other things, I doubt it will ever see the light of day (it's
sitting idle now, if anyone wants to know). I do, however, often reccomend
this program to people with lots of passwords to remember. Other similar
applications exist for the Palm Pilot of other PDAs, which protect a bank
of passwords with one password. Since most Linux geeks I know also have
PDAs, this would be a handy solution.
<P>For some real fun, though, check out FIPS 181 (1), a scheme the
government uses to generate passwords based on pronounceable sounds. It's
pretty cool, and I started playing with it (via Gpw, a related
tool(2)). And check out how Crack (3) works, it's chez pimp. For
comparison's sake, find out how L0phtCrack (4) works, and you'll snicker
at NT's security. If you're feeling particularily brave and have some
computing power to burn, consider brute forcing passwords (6), which is an
interesting problem in dictionary generation and optimization of routines.
<h3>Notes and Links:</h3>
<P>1. FIPS 181 is Federal Information processing Standard 181. The
document can be found (with source for DOS) at <A
href="http://www.itl.nist.gov/fipspubs/fip181.htm">http://www.itl.nist.gov/fipspubs/fip181.htm</a>.
A companion FIPS document, <a
href="http://www.itl.nist.gov/fipspubs/fip112.htm">FIPS 112</a>, discusses
the usage and considerations of passwords.
<P>2. Gpw is a UNIX utility in C/C++ (and Java, too) to generate
pronoucable passwords. Handy and fun. <A
href="http://www.multicians.org/thvv/gpw.html">http://www.multicians.org/thvv/gpw.html</a>
. An additional one can be found on <a
href="http://freshmeat.net/projects/apgd/">http://freshmeat.net/projects/apgd/</a>.
<P>3. Crack 5.0a source can be found at <A
HREF="http://www.users.dircon.co.uk/~crypto/">http://www.users.dircon.co.uk/~crypto/</A>.
It can also be found at <a
href="http://packetstorm.securify.com/Crackers/crack/">http://packetstorm.securify.com/Crackers/crack/</a>
<P>4. L0phtcrack... how I love thee. <A
HREF="http://www.l0pht.com/l0phtcrack/">http://www.l0pht.com/l0phtcrack/</A>
. Mudge tells us how L0phtcrack works at this realaudio presentation from
beyond Hope, 1997, NYC (1 hour) <A
HREF="http://www.2600.com/offthehook/rafiles/l0pht.ram">http://www.2600.com/offthehook/rafiles/l0pht.ram</A>
(Note that since this piece was originally written, L0phtcrack version 3
has been released. Several people have noted a dramatic drop in the
efficiency of cracking passwords, though new extraction tools have been
incoporated into the code. Many people I know who use L0phtcrack use
version 2.52 for cracking after extractions with version 3.)
<p>5. John the Ripper is another useful password cracking utility. Several
modules for cracking S/Key and MD5 passwords have been introduced lately.
<a href="http://www.openwall.com/john/">http://www.openwall.com/john/</a>.
<p>6. This is a great description of brute forcing passwords and some of
the techniques involved... I may have to try it! <a
href="http://attila.stevens-tech.edu/~khockenb/crypt3.html">The ambitious
amateur vs. crypt(3)</a>
<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Jose Nazario</H4>
<CITE>Jos&eacute; is a Ph.D. student in the department of biochemistry at Case
Western Reserve University in Cleveland, OH. He has been using UNIX for
nearly ten years, and Linux since kernels 1.2.</CITE>
<!-- *** END bio *** -->
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2001, Jose Nazario.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 68 of <i>Linux Gazette</i>, July 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">Qubism</font></H1>
<H4>By <a href="mailto:sirflakey@core.org.au">Jon "Sir Flakey" Harsem</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<IMG ALT="qb-stats.jpg" SRC="misc/qubism/qb-stats.jpg"
WIDTH="529" HEIGHT="310">
<BR CLEAR="all">
<IMG ALT="qb-mram.jpg" SRC="misc/qubism/qb-mram.jpg"
WIDTH="712" HEIGHT="309">
<BR CLEAR="all">
<IMG ALT="qb-kiddies.jpg" SRC="misc/qubism/qb-kiddies.jpg"
WIDTH="800" HEIGHT="310">
<BR CLEAR="all">
<IMG ALT="qb-getetch.jpg" SRC="misc/qubism/qb-getetch.jpg"
WIDTH="800" HEIGHT="310">
<BR CLEAR="all">
<IMG ALT="qb-emotionchip.jpg" SRC="misc/qubism/qb-emotionchip.jpg"
WIDTH="800" HEIGHT="310">
<BR CLEAR="all">
<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Jon "SirFlakey" Harsem</H4>
<CITE>Jon is the and creator of the Qubism cartoon strip and current
Editor-in-Chief of the
<A HREF="http://www.core.org.au/">CORE</A> News Site.
Somewhere along the early stages of
his life he picked up a pencil and started drawing on the wallpaper. Now
his cartoons appear 5 days a week on-line, go figure. He confesses to
owning a Mac but swears it is for "personal use".</CITE>
<!-- *** END bio *** -->
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2001, Jon "Sir Flakey" Harsem.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 68 of <i>Linux Gazette</i>, July 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">Making an X Terminal from a PC</font></H1>
<H4>By <a href="mailto:pat@swieskowski.net">Patrick Swieskowski</a></H4>
</center>
<P> <HR> <P>
<!-- END header -->
<p>An X terminal is a great way to expand the computing presence in a home or office. (We're talking about a PC that functions as an X terminal, not NEC's dedicated X-Terminal device.) They're fast, cool, a great demonstration of a Unix system's power, and, most importantly, dirt cheap. The following chronicles my experience in creating an X terminal from old PC hardware and connecting it to my <a href="http://www.debian.org/">Debian GNU/Linux</a> system.
<p>My server is a <a href="http://www.pogolinux.com/">Pogo</a> Altura with a one gigahertz AMD Athlon processor. <a href="http://www.pogolinux.com">Pogo</a> is a great company to go to if you don't want to piece together your own system or pay for a Windows license with a prebuilt system from somewhere else. I run <a href="http://www.debian.org/">Debian</a> on it, so the X terminal will use that also. That's enough background information for now.
<h2>Root filesystem setup</h2>
<p>The X terminal will boot off of a custom kernel on a floppy and then get its root filesystem over NFS from the server. The first step, then, is to create this root filesystem. You <em>could</em> copy over file after file by hand from a currently running system, or you can take a shorter approach like I did and just use the base <a href="http://www.debian.org/">Debian</a> system. All you have to do is download the base system tarball which can be found <a href="http://http.us.debian.org/debian/dists/stable/main/disks-i386/current/">on the Debian webserver</a> as the file <a href="http://http.us.debian.org/debian/dists/stable/main/disks-i386/current/base2_2.tgz">base2_2.tgz</a>. I downloaded that and did a "tar -xvzf base2_2.tgz" in /usr/xterminal and seconds later I had a fully functional root filesystem in that directory. Anyone can use the <a href="http://www.debian.org/">Debian</a> base system regardless of their server's flavor of Linux.
<p>The next step is to configure this root filesystem. I did it by becoming root and running "chroot /usr/xterminal bash --login". Now that I'm "inside" the root filesystem I duplicated my actual /etc/resolv.conf in my new root filesystem so I could use domain names during the configuration. Next we should install X, and, as any <a href="http://www.debian.org">Debian</a> user knows, the best way to do this is with apt-get. I ran "apt-get update" then "apt-get install xserver-s3 xfonts-100dpi xfonts-base", but you'll change xserver-s3 to something different if you don't have an s3 card in your X terminal (check for something suitable <a href="http://packages.debian.org/cgi-bin/search_packages.pl?keywords=xserver&searchon=names&subword=1&version=stable&release=all">here</a>.) This downloads and installs the necessary components of X. apt-get should ask you a few questions and make an XF86Config file for you, if it doesn't, or if you need to tweak the file it generates, refer to the <a href="http://www.linuxdoc.org/HOWTO/XFree86-HOWTO/index.html">XFree86 HOWTO</a>. The root filesystem is almost complete. I created an /etc/fstab file for the X terminal root that looks like this:
<pre>
10.0.0.1:/usr/xterminal / nfs defaults 0 0
proc /proc proc defaults 0 0
</pre>
<p>Of course, you'll change 10.0.0.1:/usr/xterminal to match your server IP and location of the NFS root directory. Since I have no user accounts created in this NFS root filesystem I decided to start X from init. This necessitated the following amendment to my /etc/inittab file (yours will probably have a different IP address at the end):
<pre>
X:123456:respawn:/usr/bin/X11/X -query 10.0.0.1
</pre>
<p>I'm not sure if this is perfectly correct, but it works. Finally remove the /sbin/unconfigured.sh shell script so it doesn't whine when you try to boot from your now complete root filesystem.
<h2>Building the boot floppy</h2>
<p>Next let's make the kernel. Refer to the <a href="http://www.linuxdoc.org/HOWTO/Kernel-HOWTO.html">Kernel HOWTO</a> if you aren't familiar with the kernel compile process. I tried making a boot-disk with <a href="http://www.kernel.org/pub/linux/kernel/v2.4/linux-2.4.5.tar.bz2">Kernel 2.4.5</a> but it seems as if bootp is broken in it, so I chose <a href="http://www.kernel.org/pub/linux/kernel/v2.4/linux-2.4.5.tar.bz2">Kernel 2.4.4</a> instead. Go through the regular routine (make xconfig, make dep, make bzImage) but be sure to select the following options to be compiled into the kernel (<em>not</em> as modules):
<ul>
<li>IP:BOOTP support under IP:kernel level autoconfiguration in Networking options
<li>NFS file system support and Root file system on NFS under Network File Systems in File systems (this must be selected after BOOTP support since Root on NFS will not exist until BOOTP is selected)
<li>Drivers for your NIC under Ethernet (10 or 100Mbit) in Network device support
</ul>
<p>Build your kernel and copy it to a floppy with "dd if=arch/i386/boot/bzImage of=/dev/fd0" (as root) or a similar command with your kernel and floppy drive. Since this is just a raw kernel on a floppy we need to tell it to boot over NFS. Create a /dev/boot255 device by typing (still as root) "mknod /dev/boot255 c 0 255". Now make the floppy look for its root filesystem over NFS by running (as root, of course) "rdev /dev/fd0 /dev/boot255". You can now "rm /dev/boot255" since it has no further use. Now you can set your boot floppy aside until you get your X terminal hardware.
<h2>Server setup</h2>
<p>We aren't ready to move on to hardware quite yet though, now it's time for the tricky part of server configuration. I did this on <a href="http://www.debian.org/">Debian</a> (it is so choice), so your setup for this part may differ slightly. First I installed and configured an NFS server (apt-get nfs-user-server) so the X terminal could get to its root filesystem. The configuration consists of editing the /etc/exports file. Yours should contain a line that looks like this one (the no_root_squash is important):
<pre>
/usr/xterminal 10.0.0.4/255.255.255.0(rw,no_root_squash)
</pre>
<p>The netmask (/255.255.255.0) is included so I can add more clients on my local network without listing each one independently, but just the ip address works if that's all you want. Next I installed a BOOTP server with "apt-get install bootp". To configure this I added the following line to my /etc/bootptab file:
<pre>
xterm1:vm=auto:ip=10.0.0.4:ht=ethernet:ha=00a0240d5f52:rp=/usr/xterminal
</pre>
<p>You'll probably want to change the IP, the hardware address of your NIC (it's written on it somewhere, or if you can't find it there it should be in view when the boot floppy kernel stops to look for bootp servers), and the path to the root filesystem. You'll also need to add a line like the following to your /etc/inetd.conf file:
<pre>
bootps dgram udp wait root /usr/sbin/bootpd bootpd -i -t 120
</pre>
<p>Then you'll need to have inetd reparse its configuration file by running a "killall -HUP inetd" as root. One more thing to set up, XDM. Again <a href="http://www.debian.org/">Debian</a> makes this ridiculously easy ("apt-get install xdm"). There are a few configuration files to worry about with XDM though. For me these are found under /etc/X11/xdm although yours may be somewhere else. I added the line "10.0.0.4:0 foreign" (you will probably have a different X terminal IP) to my Xservers file and commented out the ". To :0 local /usr/X11R6/bin/X -dpi 100 -nolisten tcp" line so I didn't have to login through XDM on the server. To Xaccess I appended the line "10.0.0.4" so my X terminal could connect to xdm. And finally in xdm-config I commented out (put a # infront of) the line that said "DisplayManager.requestPort: 0" so that xdm would not deny all connection attempts. The server is now set up.
<h2>Putting it all together</h2>
<p>Now for the interesting part, finding an old computer. I did not have an old box lying around so I went shopping and found one at a local used computer store. No guarantees came with my newfound 486/66, but it was only thirty bucks. By the way, this is probably the top end of X terminal hardware, anything more in the processor department would be overkill. It came with an S3Trio64 onboard (It could only do 800x600x16 so I've replaced it with a generic Trident Blade3D-based PCI video card running under the SVGA X server), and I had some RAM (32 megabytes) sitting around that I shoved in it. Another note on hardware overkill, 32 megabytes is way more RAM than an X terminal needs. Eight or sixteen would probably be fine since all it has to do is run X and the kernel. I took out everything but the floppy drive and the NIC (3Com Etherlink III), so it runs silently except for the gentle hum of the power supply fan. I plugged the monitor, ethernet patch cable, keyboard, and mouse in, put in my boot floppy, and turned it on to see (after a short boot delay) a nice XFree86 logo and a login box in X. With a cheap fifteen-inch monitor these high-quality X terminals could probably be made for $150-$200 apiece.
<p>The X terminal works great, just like I'm sitting in X on my server. If you are having problems setting this up check the relevant HOWTOS listed above or ask your local Linux guru. These instructions should work to give you nice, fast, and, best of all, cheap X terminals to put around your home or office.
<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Patrick Swieskowski</H4>
<CITE>Patrick will be a senior this fall at Roosevelt High School and
Central Academy in Des Moines, Iowa. He discovered Linux in eighth grade and
has been using it ever since.</CITE>
<!-- *** END bio *** -->
<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P -->
<H5 ALIGN=center>
Copyright &copy; 2001, Patrick Swieskowski.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 68 of <i>Linux Gazette</i>, July 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="#corrections">Corrections</a>
<!-- li><a HREF="#wacko">Wacko Topic of the Month</a -->
<li><a HREF="#nottag">Not The Answer Gang</a>
<li><a HREF="#spam">World of Spam</a>
</ul>
<a name="corrections"></a>
<P> <hr> <P>
<!--====================================================================-->
<center><H3><font color="maroon">Corrections</font></H3></center>
<P> <hr> <P>
<!--====================================================================-->
Paul Evans' <A HREF="../issue67/evans.html">Secret Tools</A> article in June's
Linux Gazette was revised June 7. The originally-published version was not the
author's final. If you read the article at the beginning of June, you may want
to <A HREF="../issue67/evans.html">read it again</A> to see what's been added.
<a name="nottag"></a>
<P> <hr> <P>
<!--====================================================================-->
<center><H3><font color="maroon">Not The Answer Gang</font></H3></center>
<P> <HR> <P>
<!--======================================================================-->
<P>
<H3 ALIGN="center">Routers vs. hubs --or-- folksongs and filksongs</H3>
<p align="right"><FONT COLOR="#000000"><strong>Answered By Iron, Ben Okopnik and
Chris Gianakopoulos
</strong></FONT></p>
</STRONG></P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Iron]
In any case, it's *certainly* a lot more topical than Ben and I
chatting away about folk songs!
</STRONG></P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Heather]
At this point, there are folk songs about free software, but no querent
has asked about 'em yet.
</STRONG></P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Chris]
All right, let's hear those folk songs about free software. What
instruments do you use. Are teletypes used instead of drums? Are radios
placed near computers for the melody? (You know -- the tones from the
speaker) And, of course, who sings those songs? I'll be yet another
curious querent.
<BLOCKQUOTE><EM>
[Astute readers will remember that Heather published her own
autobiographical filksong, <A
HREF="i../issue67/misc/tag/filksong-programmers-daughter.txt">The
Programmer's Daughter</A>, in June's Answer Gang. -Iron.]
</EM></BLOCKQUOTE>
<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ************************************** -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>A/C</H3>
<p align="right"><FONT COLOR="#000000"><strong>Answered By Iron
</strong></FONT></p>
<IMG SRC="../gx/dennis/qbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
<STRONG>i have problem in logging to my A/C. What should i do?</STRONG>
<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Iron]
You have a problem logging into your air conditioner?
Or is your alternating-current generator is going haywire?
<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ************************************** -->
<H3 align="left"><img src="../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Did Microsoft invent Linux?</H3>
<p align="right"><FONT COLOR="#000000"><strong>Answered by Iron
</strong></FONT></p>
<IMG SRC="../gx/dennis/qbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
<STRONG> Microsoft has endorsed Linux in the past. If you will remember, Linus
Tovalds developed Linux on a Microsoft research grant using kernel code
developed in Redmond by Microsoft's famous "Blue Team".
At the time, no one at Microsoft thought the code was going anywhere so they
let Linus have it and, of course, the rest is history.
SO, anytime you fire up Linux, give a hearty thanks to the people who made
it possible - Bill Gates and his buddies in Redmond.</STRONG>
<BLOCKQUOTE>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Iron]
Linus has publicly stated several times that he wrote Linux as an
exercise to learn how to program his 386 CPU. The book _Just for Fun_
is a biography of him and includes the details. The initial code all
came out of his head. It was partially a reverse-engineering of Minix,
combined with adding whatever features were necessary to get Unix
applications like GNU CC to run.
If anything, the code may have gone the other way. There are
allegations that Microsoft has borrowed code from Linux. I won't
believe it until there's proof (or at least a reasonable specificity of
what exactly they might have gotten--proof is difficult when you don't
have the source), but if it's true, it would violate the GPL, which
forbids GPL'd code from being used in a closed-source project.
</BLOCKQUOTE>
<P> <STRONG>Well I got this statement from the following link:
<A HREF="http://www.zdnet.com/tlkbck/comment/465/0,10732,113210-844545,00.html">
http://www.zdnet.com/tlkbck/comment/465/0,10732,113210-844545,00.html
</A></STRONG>
<BLOCKQUOTE>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Iron]
It's either a joke or the guy doesn't know what he's talking about.
</BLOCKQUOTE>
<a name="spam"></a>
<P> <hr> <P>
<!--====================================================================-->
<center><H3><font color="maroon">World of Spam</font></H3></center>
<P> <HR> <P>
<!--======================================================================-->
<P>
<H2><I>Linux Gazette</I> spam count</H2>
<P> I decided to take a spam count this month. The
<A HREF="../issue46/lg_backpage46.html">last time</A> I did this in 1999, the
results remained pretty stable from month to month: 28-29% of the mail LG
received was spam. I was shocked to discover the rates have reversed.
<P> This month's results are:
<TABLE BORDER>
<TR><TH ALIGN="left">Legitimate mail</TH><TD ALIGN="right">226</TD><TD ALIGN="right">30%</TD></TR>
<TR><TH ALIGN="left">Spam</TH><TD ALIGN="right">324</TD><TD ALIGN="right">70%</TD></TR>
</TABLE>
<P> "Legitimate mail" means all mail sent personally to LG or to The Answer
Gang, even those that were sincere but off-topic, as well as press releases for
News Bytes and off-topic press releases by companies that normally send stuff to
News Bytes. "Spam" includes only bulk solicitations.
<P> And now, on with the spam! (Said to tune of the Red Queen shouting,
"Off with her head!")
<P><hr><P>
<!--====================================================================-->
We wonder if you have any interest in importing tracksuits, windbreakers,
shorts, jogging suits and other sports garments from us.
<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ************************************** -->
<H3>WE'RE LETTING A MAJOR SECRET OUT OF THE BAG TODAY!</H3>
<P> The top Legal Consultant in this industry has just developed a literal cash
machine. Now, people in our activity are receiving money from all over the
place. $500 into $4,000 virtually overnight. And that's just for starters.
Everything is done for you automatically!
<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ***************************** -->
<BLOCKQUOTE><EM>
[I got a letter in a totally unfamiliar language. Thinking it might
be Turkish, I sent it to my friend Gorkem. -Iron.]
</EM></BLOCKQUOTE>
<P> Hey Mike,<BR>
It is indeed Turkish. In case you want to publish it, I am enclosing a
translation
<IMG SRC="../gx/dennis/smily.gif" ALT=":-)"
height="24" width="20" align="middle">
It is of course pure spam.<BR>
Gorkem
<P> Subject: Re: Cinsel problemlerinize son verebilirsiniz.
<P> Cinsel Problemlere Kalici ve Kesin Cozumler<BR>
<EM>Decisive and Permanent Solutions to your Sexual Problems</EM><BR>
Ereksiyon sorunlari, iktidarsizlik, performans arttirma...<BR>
<EM>Erectile problems, impotency, increasing performance...</EM><BR>
Erken bosalma sorunlari ve penis buyutme teknikleri<BR>
<EM>Premature ejaculation problems and penis enlargement techniques</EM><BR>
(ameliyatsiz/vakumsuz)...<BR>
<EM>(no operations / no vacuum pumps)</EM><BR>
Bayanlarda isteksizlik, orgazm sorunlari ve firijitlik...<BR>
<EM>Low sexual desire, orgasm problems and frigidity in women</EM><BR>
Turk toplumunun yabanci oldugu cinsellik bilgileri ve seks teknikleri...<BR>
<EM>Sexuality information that is foreign to the Turkish society and sexual techniques</EM><BR>
<P> Mutluluklar dilerim.</EM><BR>
<EM>The wishes of happiness.</EM><BR>
Saygilarimla,<BR>
<EM>Respectfully</EM><BR>
Dr. XXXX XXXX
<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ***************************** -->
We have reviewed several online credit card programs and feel that the
XXXXX MasterCard
is one of the best for anyone who needs a credit card. With the XXXXXX
program you are
ABSOLUTELY GUARANTEED APPROVAL ONLINE. No credit checks and no
credit turndowns.
<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ***************************** -->
<P> This is a personal invitation for you to be a part
of our private association. We are a group of successful
entrepreneurs with backgrounds specializing in helping
others achieve financial success.
<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ***************************** -->
<P> Local governments in Florida are considering tougher penalties for traffic
violators who run red lights.
<P> Should the fines be doubled?
<P> To tell Florida officials what you think, click the following link.
<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ***************************** -->
<P> Le nuove estensioni .biz e .info sono state approvate dall ICANN,
l'authority che regola il sistema dei nomi di dominio.
Entro il 2001 inoltre sar&agrave; disponibile anche l' estensione .eu, richiedi
il dominio che vuoi adesso, prima che diventi disponibile per la
registrazione, con il nostro modulo di richiesta.
L'inizio della registrazione ufficiale &egrave; previsto per il 17 di agosto nel
caso dei domini .info, e per il 31 di ottobre per quelli .biz.
Tuttavia gi&agrave; fin d'ora puoi pre-registrare il Tuo nome di dominio, in
questo modo la tua richiesta sar&agrave; inviata agli enti registranti prima
delle altre e avrai cosi pi&ugrave; possibilit&agrave; di ottenere il tuo nome.
<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ***************************** -->
<P> I visited &lt;http:///&gt;ssc and I'm sure that you could get much more
money only by including your own TELEPHON LIVE CHAT inside your site. Upgrade
your site with CONTACTEL system FOR FREE and get money from more than 20
countries for the traffic received on your TELEPHON PARTY-LINE.
<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ***************************** -->
<P> This E-Mail does NOT contain any hype, just facts.
<HR NOSHADE WIDTH="80%"> <!-- ************************************** -->
<P> Happy Linuxing!
<P> Mike ("Iron") 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; 2001, 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 68 of <i>Linux Gazette</i>, July 2001</H5>
<!-- *** END copyright *** -->
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