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1034 lines
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<TITLE>Linux Gazette July, 1995</TITLE>
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<H1><IMG ALIGN=MIDDLE SRC="./gx/homeboy_icon.gif">Linux Gazette July, 1995</H1>
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<H3>A Publication of the Linux HomeBoy WebPage Series</H3>
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<H5>Copyright (c) 1995 John M. Fisk <I>fiskjm@ctrvax.vanderbilt.edu</I><BR><BR>
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The LINUX GAZETTE is now a member of the LINUX DOCUMENTATION PROJECT.<BR>
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For information regarding copying and distribution of this material see the
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<A HREF="./copying.html">COPYING</A> document.<BR>
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Linux Home Boy Pages logo created using <EM>David Koblas'</EM> excellent
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program XPAINT 2.1.1 </H5>
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<HR>
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<H2> Topics in this <EM>premier</EM> issue include:</H2>
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<UL>
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<LI><A HREF="#whatis">So what <I>is</I> the Linux Gazette...</A>
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<LI><A HREF="#offwego">And off we go...</A>
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<LI><A HREF="#motd">So what <I>is</I> this MOTD thingy...</A>
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<LI><A HREF="#alias">Aliasing for fun and efficiency</A>
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<LI><A HREF="#functions">Adding some functions for even more time savings</A>
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<LI><A HREF="#au">Playing .AU at boot up</A>
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<LI><A HREF="#mounting">Mounting your cdrom and floppies the <I>easy</I> way</A>
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<LI><A HREF="#configs">Managing your wandering system configuration files</A>
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<LI><A HREF="#ext2tool">Accessing Linux from DOS!?</A>
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<LI><A HREF="#kernel">Rolling your own kernel... it ain't that tough</A>
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<LI><A HREF="#testdrive">Test driving you new kernel the safe way</A>
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<LI><A HREF="#thatsit">Well, that's it</A>
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</UL>
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<BR>
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<HR>
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<A NAME="whatis"><H2><IMG ALIGN=BOTTOM SRC="../gx/text.gif">So what <I>is</I> the Linux Gazette... </H2></A>
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<P>Primarily writings, ramblings, and other stuff...
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<P>About a year ago, after getting my first glimpse of the internet via a dial-up
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2400 baud VAX account (<EM>ouch!...</EM>), I started reading about a freely available
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UN*X-like operating system that would let you run a unix operating system on an i386
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or better PC. Sounded good to me...
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<P>So... after spending <EM>days</EM> tying up the dial-up line into the wee hours
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of the morning, AND after spending 45 bucks in floppies, I finally managed to get
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a copy of <B>Slackware 2.0.0</B>. I spent an entire afternoon thereafter shoveling
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disks in and out of my PC and watching dialog after dialog describe what was happening.
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Eventually, I managed to get it all loaded up, rebooted, and <STRONG>presto!</STRONG>...
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<P><B>LINUX!</B>
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<P>I got hooked! This thing was awesome, huge, and bewildering. At times it was
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so frustrating that I was sure it was either a 120MB virus in disguise... or possessed.
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Eventually, I started making some headway and things worked! Now, I was really
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hooked. What had happened was that by reading everything I could find --
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<UL>
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<LI>comp.os.linux.*
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<LI>The Linux User's Guide (from the Linux Documentation Project (LDP))
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<LI>Linux Installation and Getting Started (LDP)
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<LI>the Network Administrator's Guide (LDP)
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<LI>the System Administrator's Guide (LDP)
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<LI>a <B>boatload</B> of FAQ's and HOWTO's
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<LI><I>Running Linux</I> by Matt Welsh and Lar Kaufman (published by O'Reilly)
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<LI><I>Linux - Unleashing the Workstation in Your PC</I> by Stephan Strobel and
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Thomas Uhl (published by Springer-Verlag)
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<LI><I>X Window System Uer's Guide</I> by Valerie Querica and Tim O'Reilly (published by
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O'Reilly)
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<LI>and several general books on UNIX such as <I>A Student's Guide to UNIX</I> by
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Harley Hahn, <I>Essential System Administration</I> by Aeleen Frisch, and
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<I>Shell Programming</I> by Kamran Husain.
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</UL>
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and then playing around with things until they either worked or broke (fortunately,
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mostly the former :-), Linux finally <EM>began to make sense to me.</EM>
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<P>If you're in the same boat... keep paddling! The result is definitely worth it!
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Running Linux means having to do your homework. It's a matter of reading and learning
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until things make sense. There are LOTS of folks out there who are more than willing
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to help and have invested a LOT of time into writing the documentation that makes
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Linux knowable.
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<P>Great software without the knowledge to run it is pretty useless.
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<P>Sermon over. What I've tried to do with the <B>Linux Gazette</B> is pass along
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some of the ideas that I've tried, liked, and have worked for me. Just one caveat:
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<P><STRONG>This ain't technical wizardry and it won't advance you to gurudom...</STRONG>
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<P>Hopefully, what it will do is make running Linux a bit more fun, enjoyable, or
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easier. This is a compilation of ideas I've shamelessly plagerized from so many
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sources that, quite frankly, I'm not sure where some of them came from, let alone
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being able to give due credit to the originator. And so... <B>to the great nameless,
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faceless, unknown but all-knowing Linux gurus</B> (ooh, kinda spooky, eh?)...
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<P>Thanks.
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<BR><BR>
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<A HREF="#toc"><IMG ALIGN=BOTTOM SRC="./gx/toc.gif"></A>
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<A HREF="mailto: fiskjm@ctrvax.vanderbilt.edu"><IMG ALIGN=BOTTOM SRC="./gx/sendmail.gif"></A>
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<A HREF="./gazette_toc.html"><IMG ALIGN=BOTTOM SRC="./gx/index.gif"></A>
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<A HREF="./linux/linux.html"><IMG ALIGN=BOTTOM SRC="./gx/home.gif"></A>
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<BR><BR>
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<HR>
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<A NAME="offwego"><H2><IMG SRC="../gx/text.gif">And off we go...</H2></A>
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<P>What I'll try to do is make this as pleasant, or at least as painless, as possible.
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It's admittedly a bit loose and rambly and probably best purused when you've got a
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bit of time to browse...
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<P>eh?... what?! Your student account at rigid.frigid.toxic-megahosers.edu times
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you out at 2 minutes of inactivity?! Hosers.
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<P>Try this. If you're running a PPP account set up a small shell script:
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<PRE>
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#!/bin/sh
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#program: hose-em
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#purpose: keeps a dial-up line from timing out while you're
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# reading Web stuff or doing your laundry (OK... let's be
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# responsible)
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#
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# We'll use the gateway server as your host.
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HOST=000.00.00.000 # the dotted-quad address of your gateway which
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# you can get by typing "ifconfig"
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SLEEP=8m # how long we'll wait between pings
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###############################################################################
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#
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# Set up a while loop that pings the host as long as the PID file exists.
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# But first, make sure that the connection is still up.
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#
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if [ -e "/var/run/ppp0.pid" ]; then
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echo "
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* * * PPP-UP is running * * *
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"
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else
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echo "
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* * * PPP0 interface is not up! * * *
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"
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exit 1
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fi
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while [ -e "/var/run/ppp0.pid" ] # Now, set up the while loop.
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do # As long as the PID file exists
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ping -c 1 $HOST > /dev/null # we'll ping the host once every 8 min.
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sleep $SLEEP
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done
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exit 0
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</PRE>
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you'll notice we use the <CODE>ping -c 1</CODE> designation -- that keeps ping from
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endlessly pinging. Set the variable <CODE>SLEEP=</CODE> to whatever interval you
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need. And that's it! Don't forget to <CODE>chmod 711 hose-em</CODE> when you're
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done.
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<P>Now, you can browse in peace. When you terminate the link, the while-loop ends
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and ping goes back to sleep.
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<BR><BR>
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<A HREF="#toc"><IMG ALIGN=BOTTOM SRC="./gx/toc.gif"></A>
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<A HREF="mailto: fiskjm@ctrvax.vanderbilt.edu"><IMG ALIGN=BOTTOM SRC="./gx/sendmail.gif"></A>
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<A HREF="./gazette_toc.html"><IMG ALIGN=BOTTOM SRC="./gx/index.gif"></A>
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<A HREF="./linux/linux.html"><IMG ALIGN=BOTTOM SRC="./gx/home.gif"></A>
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<BR><BR>
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<HR>
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<A NAME="motd"><H2><IMG SRC="../gx/text.gif">So what is this MOTD thingy and <I>who keeps eating my issue...!</I></H2></A>
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<P>Ever notice that when you log into Linux you get the same ol'
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<PRE>
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Welcome to Linux 1.x.x.
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Login:
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Linux 1.x.x. (POSIX)
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</PRE>
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...and you finally discover <B>/etc/issue</B> and <B>/etc/motd</B>. And after
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hacking away on them until they finally say <I>anything</I> besides the usual
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brain-dead information about what kernel this is... you reboot.. <B>and there it
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is AGAIN!!</B>. Arggghhh!
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<P>So what happened? There's a line of code in your /etc startup files that
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resets the /etc/issue and /etc/motd files back to their original. BTW... /etc/issue
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is the first message that is displayed immediately before the login prompt, while
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/etc/motd (Message Of The Day) is displayed once a user has successfully logged in.
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<P>To fix this you'll need to edit one of those obscure config files in your
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/etc/rc.d directory. You'll need to edit /etc/rc.d/rc.S and look for:
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<PRE>
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# Setup the /etc/issue and /etc/motd to reflect the current kernel level:
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# THESE WIPE ANY CHANGES YOU MAKE TO /ETC/ISSUE AND /ETC/MOTD WITH EACH
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# BOOT. COMMENT THEM OUT IF YOU WANT TO MAKE CUSTOM VERSIONS.
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echo > /etc/issue
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echo Welcome to Linux `/bin/uname -a | /bin/cut -d\ -f3`. >> /etc/issue
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echo >> /etc/issue
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echo "`/bin/uname -a | /bin/cut -d\ -f1,3`. (POSIX)." > /etc/motd
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</PRE>
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If you look closely at what this does, it echo's several lines into your
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/etc/issue file, thereby wasting whatever you'd previously written, and it does
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the same with your /etc/motd file. Now, thing to do is comment these out by
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simply putting a " # " in the beginning of each of these lines. Now,
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you can go ahead and edit your <B>issue</B> and <B>motd</B> files and know that
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when you boot up again... they'll be there!
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<BR><BR>
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<A HREF="#toc"><IMG ALIGN=BOTTOM SRC="./gx/toc.gif"></A>
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<A HREF="mailto: fiskjm@ctrvax.vanderbilt.edu"><IMG ALIGN=BOTTOM SRC="./gx/sendmail.gif"></A>
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<A HREF="./gazette_toc.html"><IMG ALIGN=BOTTOM SRC="./gx/index.gif"></A>
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<A HREF="./linux/linux.html"><IMG ALIGN=BOTTOM SRC="./gx/home.gif"></A>
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<BR><BR>
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<HR>
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<A NAME="alias"><H2><IMG SRC="../gx/text.gif">Aliasing for fun and efficiency...</H2></A>
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<P>While we're talking about fixing up boot up stuff... if you're using <B>bash</B> (which
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most folks running Linux probably are since it's often installed by default) then
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there's a great little config file you need to get aquainted with:
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<P>Your ~/.bash_profile
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<P><B>Two cent tip:</B> the squiggly-thingy (" <EM>tilde</EM> ") just
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indicates your <EM>home</EM> directory. It should point to the same directory that
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the environment variable $HOME points to.
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<P>If you browse the manpage for <B>bash</B> you'll discover that there are several
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configuration files that can be read at the time of initialization
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<UL>
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<LI>/etc/profile -- the systemwide initialization file executed for login shells
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<LI>~/.bash_profile -- the personal initialization file, executed for login shells
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<LI>~/.bashrc -- the individual per-interactive-shell initialization file
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</UL>
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What this means is that you can set up your own personal initialization setup each
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time you login. <EM>And that's where aliases come in.</EM>
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<P>Aliases are command substitutions, if you will, that can be used with certain
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shells such as bash. The syntax is:
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<PRE>
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alias shortcut=`command -options`
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</PRE>
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Notice the use of the <CODE> "`" </CODE> after the equals sign (you know, the backwards
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apostrophe that lives underneath the squiggly thingy on the top of the keyboard).
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<P>Now... make life easier for yourself. If you set up shortcut aliases you can
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speed up your keyboard commands considerably. Some examples:
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<PRE>
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alias c='clear'
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alias d='ls -lF'
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alias dir='ls -lF'
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alias ftp='ftp -v'
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alias lpr='lpr -h'
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alias rm='rm -i'
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alias startx='startx >& /dev/null'
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alias x='startx >& /dev/null'
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</PRE>
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You'll notice that this speed things up a lot. Instead of constantly typing out
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ls -lF for a directory listing you simply enter " d " . Also, if you're
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running X Window <EM>and you're tired of looking at all the startup information
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cluttering your screen when you shut it down</EM> then adding an alias to send
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the usual stdout into the /dev/null bitbucket clears up your screen. Nice and
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tidy.
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<P>Notice one other thing -- a safety point. As long as you're not running as
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root all the time you're probably safe from the standpoint of not fatally and
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irretrievably zapping some critical system file. But you can still effortlessly
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do away with hours/days/weeks of work on a file if you inadvertently " rm "
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something you hadn't intended. UN*X can be kinda harsh, and Linux is no different.
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Once somethings gone... it's gone. Now there are programs that handle safe deletes,
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but the plain vanilla Linux will still uncaringly discard anything you tell it to.
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<P>By adding an alias for " rm " -- so that it is always invoked with the
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-i option, it will always ask you for permission to delete something. Yup, it's can
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be a bit of an annoyance, but if it saves your butt once, you'll be happy that you
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did. Also, you <EM>can</EM> override this by issuing " rm -f delete_me.text "
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and Linux will happily delete it without another thought.
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<BR><BR>
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<A HREF="#toc"><IMG ALIGN=BOTTOM SRC="./gx/toc.gif"></A>
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<A HREF="mailto: fiskjm@ctrvax.vanderbilt.edu"><IMG ALIGN=BOTTOM SRC="./gx/sendmail.gif"></A>
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<A HREF="./gazette_toc.html"><IMG ALIGN=BOTTOM SRC="./gx/index.gif"></A>
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<A HREF="./linux/linux.html"><IMG ALIGN=BOTTOM SRC="./gx/home.gif"></A>
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<BR><BR>
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<HR>
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<A NAME="functions"><H2><IMG SRC="../gx/text.gif">Adding some functions for even more time savings</H2></A>
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<P>Well, now that we've added some helpful aliases, let's make life even more fun
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and efficient...
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<P>Adding functions to the ~/.bash_profile.
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<P>Yup, you remember the idea of functions -- the short bits of little-black-box
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code that takes in input and spits back some kind of output. Well, you can set the
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same basic thing up, only in a more modest fashion.
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<P>Under <B>bash</B> you can define functions that work in your shell script programs
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by defining them like:
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<PRE>
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Say_hello()
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{
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echo "Hello world"
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}
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</PRE>
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Now, if you invoke the function Say_hello, you'll get a profound sense of accomplishment
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as it issues a " Hello world " back. Pretty lame, eh? Well, not so fast.
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You can use this bit of wizardry in your ~/.bash_profile to set up commonly used
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functions. Like what? Well, if you use <B>tar</B> frequently, then it's helpful
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to add something like:
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<PRE>
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# Now, some handy functions...
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#
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tarc () { tar -cvzf $1.tar.gz $1 }
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tart () { tar -tvzf $1 | less }
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tarx () { tar -xvzf $1 $2 $3 $4 $5 $6 }
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popmail () { popclient -3 -v -u myname -p mypassword -o /root/mail/mail-in any.where.edu }
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zless () { zcat $* | less }
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z () { zcat $* | less }
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</PRE>
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to your ~/.bash_profile initialization file. Now, instead of having to type out
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<CODE>tar -xvzf some_very_long_filename-3.1415926535-bin-Motif-static.tar.gz</CODE>
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you can just type in <CODE>tarx some_ver</CODE> (and then hit TAB to do a filename
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completion... just because UN*X allows 256-character file names <EM>doesn't</EM>
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mean that you actually have to <EM>USE</EM> all 256 characters). The function call
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will do the rest. An even handier situation is if you've got an excruciatingly long
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command line to enter, such as for the program <B>popclient</B>.
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<P>For short functions you can just as easily set up an alias. Someone with more
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UN*X wizardry than me might be able to say whether one is more efficient/desirable
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than the other. Fact is, they both work, and they'll both let you save a LOT of
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time if your spending much time at the keyboard.
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<P>One final point... you can use this basic idea to save yourself some harddrive
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space. How?
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<P>If you <B>gzip -9</B> your documentation files (you probably don't want to do
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this with your /etc/inittab file) then it's easy to view them by setting up a
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function or alias such as " z " , which is listed above. This will <B>zcat</B>
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the compressed file and pipe it to <B>less</B> (or <B>more</B> if you like that)
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for viewing. On my machine this action is nearly instantaneous for all but the most
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gigantic files.
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<BR><BR>
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<A HREF="#toc"><IMG ALIGN=BOTTOM SRC="./gx/toc.gif"></A>
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<A HREF="mailto: fiskjm@ctrvax.vanderbilt.edu"><IMG ALIGN=BOTTOM SRC="./gx/sendmail.gif"></A>
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<A HREF="./gazette_toc.html"><IMG ALIGN=BOTTOM SRC="./gx/index.gif"></A>
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<A HREF="./linux/linux.html"><IMG ALIGN=BOTTOM SRC="./gx/home.gif"></A>
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<BR><BR>
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<HR>
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<A NAME="au"><H2><IMG SRC="../gx/text.gif">Playing .AU stuff at boot up</H2></A>
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<P>For any of you that have a sound card and have had the unfortunate pleasure of
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firing up <EM>Windoze</EM> you'll recall the scratchy, irritating .wav <EM>noise</EM>
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that eminates from your speakers. This fingernails-on-the-chalkboard greeting reminds
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you of what you have in store...
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<P>Fortunately, you can do a lot better than the cheesy <CODE>ding.wav</CODE>
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thing. Linux is here to rescue you. First, you'll need to get your hands on some
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half-way decent .au files -- try the <B>multimedia</B> subdirectory at
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<A HREF="ftp://sunsite.unc.edu/pub/multimedia/sun_sounds/">sunsite.unc.edu</A>
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for a veritable smorgasbord of great .au sound files.
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<P>(In case you need some hints, there are great trekky clips, some wonderful stuff
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by Monty Python -- try out spam.au and the lumberjack.au files -- as well as the
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classics from the Three Stooges in the
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<A HREF="ftp://sunsite.unc.edu/pub/multimedia/sun_sounds/series/three_stooges/">
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/series/three_stooges</A> subdirectory)
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<P>Once you've gotten a few good .au files, you can make logging in a much more
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rewarding and eventful experience by adding something like this to your /etc/rc.d/rc.local
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file:
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<PRE>
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cat /usr/local/sound/spam.au > /dev/audio &
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</PRE>
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If you put this at the end of the file, after all the other housekeeping chores are
|
|
done, then you'll be greeted with a rousing rendition of "Spam, Spam, Wonderful Spam"
|
|
in four part harmony (...honest!) as the login prompt is displayed. One minor point --
|
|
don't forget to add the " & " at the end of the command line or else
|
|
you'll find yourself having to sit throught the ENTIRE rendition before it gives up
|
|
control to the login prompt.
|
|
|
|
<BR><BR>
|
|
<A HREF="#toc"><IMG ALIGN=BOTTOM SRC="./gx/toc.gif"></A>
|
|
<A HREF="mailto: fiskjm@ctrvax.vanderbilt.edu"><IMG ALIGN=BOTTOM SRC="./gx/sendmail.gif"></A>
|
|
<A HREF="./gazette_toc.html"><IMG ALIGN=BOTTOM SRC="./gx/index.gif"></A>
|
|
<A HREF="./linux/linux.html"><IMG ALIGN=BOTTOM SRC="./gx/home.gif"></A>
|
|
<BR><BR>
|
|
|
|
<HR>
|
|
|
|
<A NAME="mounting"><H2><IMG SRC="../gx/text.gif">Mounting your cdrom and floppies the <I>easy</I> way</H2></A>
|
|
|
|
<P>Ok, we're on a roll here... While we're messing around with all the initialization
|
|
stuff it's time to hack away on something else.
|
|
|
|
<P>The <B>/etc/fstab</B> file.
|
|
|
|
<P>Here are just a couple suggestions to make life easier.
|
|
|
|
<P>First, for all of you who've upgraded to kernel 1.2.x and have suddenly found
|
|
yourself getting the same annoying error message at bootup... you know, something
|
|
about your /etc/fstab lacking a passno field entry... well, here's how to make
|
|
things right.
|
|
|
|
<P>The problem is that <B>mount</B> is now looking for two additional field in the
|
|
/etc/fstab file -- the fifth (fs freq) and the sixth (fs passno) fields -- which
|
|
are not, at least as yet, included by default in the stock <B>Slackware</B> distribution
|
|
of Linux. So, after you've installed everything correctly, you <EM>still</EM>
|
|
end up getting an error message. Time to fix it.
|
|
|
|
<P>The manpage for <B>fstab</B> is actually quite intelligible when it comes to
|
|
the entries. What's important, at least to rid yourself of the annoying error
|
|
message, is to know that two additional fields have been set up for each file
|
|
system entry. The <B>fifth field</B> (fs freq)has to do with information regarding the
|
|
<B>dump</B> (?) program -- it specifies which filesystems need to be <B>dumped</B>.
|
|
(?) ... I'm not sure either, but I've read that it's safe to simply put in a
|
|
" 0 " and let it go at that.
|
|
|
|
<P>The <B>sixth field</B> (fs passno) is the one of interest. It contains a numerical value
|
|
used by the <B>fsck</B> program at boot time to determine the order in which filesystems
|
|
are checked. The rules are
|
|
|
|
<P><B>The root filesystem is given a value of 1</B><BR>
|
|
<B>Other filesystems are given a value of 2</B><BR>
|
|
<B>File systems that do not need checking -- such as the /proc or /cdrom -- are
|
|
given a value of 0</B>
|
|
|
|
<P>So, your fstab might look something like this:
|
|
|
|
<PRE>
|
|
|
|
# entries for file system table "fstab". File systems are entered in a format:
|
|
#
|
|
# device: mount: fs-type: options: dump: fsck:
|
|
# _______ ______ _______ ________ ____ ____
|
|
#
|
|
/dev/hda6 / ext2 defaults 0 1
|
|
/dev/hdb7 swap swap defaults 0 0
|
|
/dev/hda2 /dosc msdos defaults 0 2
|
|
/dev/hdb5 /os2 msdos defaults 0 2
|
|
/dev/hdb6 /dosf msdos defaults 0 2
|
|
none /proc proc defaults 0 0
|
|
#
|
|
# These last five are for the CDROM and floppy drives A and B. The fs-type
|
|
# is indicated and the 'noauto' keeps init from trying to automount the fs
|
|
# at bootup. The option 'user' *should* allow normal non-root users to mount
|
|
# the fs.
|
|
#
|
|
/dev/sbpcd /cdrom iso9660 ro,noauto 0 0
|
|
/dev/fd0 /a msdos user,noauto 0 0
|
|
/dev/fd1 /b msdos user,noauto 0 0
|
|
/dev/fd0 /fd0 ext2 user,noauto 0 0
|
|
/dev/fd1 /fd1 ext2 user,noauto 0 0
|
|
|
|
</PRE>
|
|
|
|
So what's going on here?
|
|
|
|
<P>When you boot your system, there's a line in your /etc/rc.d/rc.S file that
|
|
looks like:
|
|
<PRE>
|
|
/sbin/mount -avt nonfs
|
|
</PRE>
|
|
|
|
at least this is what's in the plain vanilla Slackware distribution, your's may
|
|
vary. The <B>mount</B> command with the <B>-a</B> option results in the automatic
|
|
mounting of all the filesystems in your /etc/fstab file <EM>execept those that
|
|
have the noauto option</EM> .
|
|
|
|
<P>So, if you look at what's going on, you'll see that in the above example, there
|
|
are several filesystems automatically mounted at boot time and include a Linux
|
|
native (/dev/hda6), a Linux swap (/dev/hdb7), a couple DOS partitions (/dev/hda2 and
|
|
/dev/hdb6), an OS/2 (FAT partition, hence the " msdos " fs-type) (/dev/hdb5)
|
|
and the /proc filesystem.
|
|
|
|
<P>What you'll also notice is that, in the lower section of the fstab file, there
|
|
are several stanza's with the " noauto " option indicated.
|
|
|
|
<P><B>Here's where life get's easier</B>
|
|
|
|
<P>Adding the " noauto " option keeps <B>mount</B> from trying to mount
|
|
my cdrom or floppies at boot time -- since it's likely that there's nothing there.
|
|
However, when I'm ready to mount one of these, instead of having to type the usual
|
|
|
|
<P>mount -r -t iso9660 /dev/sbpcd /cdrom
|
|
|
|
<P>I can simply type in:
|
|
|
|
<P>mount /cdrom
|
|
|
|
<P>Mount will look in the fstab file and if it finds an entry for /cdrom it'll go
|
|
ahead and mount it with the options specified. <B>Two other quick points</B>:
|
|
By setting up /a and /fd0 entries for /dev/fd0, and /b and /fd1 entries for /dev/fd1
|
|
I can easily mount floppies that are either in DOS or ext2 format by entering:
|
|
|
|
<P><B>mount /a</B> for DOS floppies or<BR>
|
|
<B>mount /fd0</B> for ext2 floppies
|
|
|
|
<P>And adding the " user " option allows me to mount the filesystem as a
|
|
<EM>non-root</EM> user.
|
|
|
|
<P>Slick, eh? <B>Linux</B> is excellent.
|
|
|
|
<BR><BR>
|
|
<A HREF="#toc"><IMG ALIGN=BOTTOM SRC="./gx/toc.gif"></A>
|
|
<A HREF="mailto: fiskjm@ctrvax.vanderbilt.edu"><IMG ALIGN=BOTTOM SRC="./gx/sendmail.gif"></A>
|
|
<A HREF="./gazette_toc.html"><IMG ALIGN=BOTTOM SRC="./gx/index.gif"></A>
|
|
<A HREF="./linux/linux.html"><IMG ALIGN=BOTTOM SRC="./gx/home.gif"></A>
|
|
<BR><BR>
|
|
|
|
<HR>
|
|
|
|
<A NAME="configs"><H2><IMG ALIGN=BOTTOM SRC="../gx/text.gif">Managing your wandering system configuration files</H2></A>
|
|
|
|
<P>I suspect that <EM>most people</EM> who are running Linux have found themselves,
|
|
for better or for worse, the <I>de facto</I> sysadmin of their workstation. Yeah,
|
|
it's cool to be root but it can also be a major league <EM>pain-in-the-butt</EM> .
|
|
|
|
<P><B>Here's another two cent tip to make life easier.</B>
|
|
|
|
<P>If you've run Linux for any length of time you've probably ended up making a
|
|
<B>boatload of changes</B> to the system. If you haven't done so already, you
|
|
should probably made a subdirectory off your /root directory and put <B>copies of
|
|
ALL the system configuration files</B> that were installed by your distribution.
|
|
|
|
<P>So, you create a <B>/config_dist</B> subdirectory and start to collect some files:
|
|
<UL>
|
|
<LI>/etc/inittab
|
|
<LI>/etc/profile
|
|
<LI>/etc/rc.d/rc.*
|
|
<LI>/etc/passwd
|
|
<LI>/usr/X11R6/lib/X11/XF86Config
|
|
</UL>
|
|
then if the system crashes because you screwed something up, you've
|
|
got a backup copy to restore it to its original state.
|
|
|
|
<P>The prepared mind.
|
|
|
|
<P><B>One more suggestion...</B>
|
|
|
|
<P>After you've created a subdirectory to save all the original config files, create
|
|
another subdirectory called <B>/links</B>. Now, for all of your widely scattered
|
|
configuration files, <EM>create symlinks for them in your /links directory.</EM>
|
|
|
|
<P>So, if you're messing around with trying to get your PPP setup going, make a link
|
|
to /etc/ppp/options or /usr/lib/ppp/pppon:
|
|
|
|
<PRE>
|
|
cd ~/links
|
|
ln -s /etc/ppp/options ppp_options
|
|
ln -s /usr/lib/ppp/pppon pppon
|
|
</PRE>
|
|
|
|
Now, when you cd to your /links directory, you'll find symlinks to your various
|
|
config files. Then, if you need to make any further changes in them, you can easily
|
|
do so from anywhere in your system by entering <B>vi ~/links/ppp_options</B>. Having
|
|
all the system configuration files symlinked to one directory makes housekeeping a bit
|
|
easier. Some further ideas about what to include:
|
|
<UL>
|
|
<LI>/etc/printcap -- if you've had to set up your printcap file
|
|
<LI>/var/spool/lpd/filter_myprinter -- if you've had to create an input filter
|
|
<LI>/etc/rc.d/rc.* -- pretty much <EM>all</EM> the stuff here
|
|
<LI>/usr/lib/ppp/ppp* -- <I>ibid.</I>
|
|
<LI>/usr/X11R6/lib/X11/fvwm/system.fvwmrc -- for all the groovy stuff you've done to FVWM
|
|
</UL>
|
|
and so forth. You get the idea. Every time you have to make an adjustment you go
|
|
throught this simple process:
|
|
<OL>
|
|
<LI>make a copy of the original file and call it original_filename<I>.dist</I>
|
|
<LI>copy that original_filename<I>.dist</I> to your /config_dist directory
|
|
<LI>make whatever alterations and customizations you want
|
|
<LI>make a symlink to your new-and-improved config file in your ~/links directory
|
|
<LI>now enjoy the fruits of your labors, or fix what you've just broken
|
|
</OL>
|
|
|
|
<P>Thing is... why go through all the bother of doing this <EM>by hand</EM> when
|
|
you can create a simple shell script that makes life MUCH easier.
|
|
|
|
<P><B>Two cent tip:</B> if you have a long, repetitive task then think seriously
|
|
about writing a shell script to automate the process. Remember: you're not running
|
|
MSDOG, <B>this is Linux</B>. Try something like:
|
|
|
|
<PRE>
|
|
|
|
#!/bin/sh
|
|
#
|
|
# program: hack
|
|
# author: johnMfisk 7 july 1995
|
|
# purpose: create a backup and a symlink to an important system file.
|
|
#
|
|
CURR_DIR=`pwd`
|
|
|
|
cp $1 "/root/config_dist/$1.dist"
|
|
ln -s "$CURR_DIR/$1" "/root/links/$1"
|
|
vi $1
|
|
exit
|
|
|
|
</PRE>
|
|
|
|
<P>Don't forget to " <CODE>chmod 700 hack</CODE> " when you're done. Then, every time
|
|
you need to alter a system configuration file, you simply enter in:
|
|
|
|
<P><B> hack important_sys_file.cfg</B>
|
|
|
|
<P>Hack creates a backup copy in your /config_dist directory with the
|
|
" .dist " suffix; then it creates a symlink to the file in your /links
|
|
directory; and finally, it fires up <B>vi</B> (or whatever other editor you like)
|
|
and let's you make your changes. This is a pretty barebones example, and you could
|
|
easily spiff it up by, for instance, testing for the existance of the file in your
|
|
/config_dist directory and not copying over it if it already exists, or asking for
|
|
permission to copy over it.
|
|
|
|
<BR><BR>
|
|
<A HREF="#toc"><IMG ALIGN=BOTTOM SRC="./gx/toc.gif"></A>
|
|
<A HREF="mailto: fiskjm@ctrvax.vanderbilt.edu"><IMG ALIGN=BOTTOM SRC="./gx/sendmail.gif"></A>
|
|
<A HREF="./gazette_toc.html"><IMG ALIGN=BOTTOM SRC="./gx/index.gif"></A>
|
|
<A HREF="./linux/linux.html"><IMG ALIGN=BOTTOM SRC="./gx/home.gif"></A>
|
|
<BR><BR>
|
|
|
|
<HR>
|
|
|
|
<A NAME="ext2tool"><H2><IMG ALIGN=BOTTOM SRC="../gx/text.gif">Accessing Linux from DOS!?</H2></A>
|
|
|
|
<P>Face it, a lot of folks who use Linux are actually converts from other OS's such
|
|
as DOS or Windoze. And in reality, a lot of folks are actually in the <EM>multiple-OS</EM>
|
|
catagory. There's a lot of software that we've spent good money on or just simply
|
|
like that either can't be run, or doesn't run well, under a non-native OS. The
|
|
simple fact is, no one OS is perfect enough to run everything you'd like to run
|
|
(and that goes <EM>double</EM> for Bill Gate$ and Co.)
|
|
|
|
<P>Fortunately, Linux comes with filesystem support for accessing your DOS FAT
|
|
partitions. It'll read from and write to your DOS filesystem. There's also work
|
|
that's ongoing to provide both DOS emulation (<B>DOSEMU</B>) and Windows 3.1 emulation
|
|
(<B>WINE</B>) that would allow you to run your DOS and Win 3.1 programs directly from
|
|
Linux. If you're interested in this kind of thing check out the
|
|
<A HREF="http://sunsite.unc.edu/mdw/linux.html">Linux Documentation Project</A>
|
|
web page for HOWTO's and other information.
|
|
|
|
<P>At present, there's a handy little program called
|
|
<A HREF="ftp://ftp.cc.gatech.edu/pub/linux/system/Filesystems/ext2/ext2tool.zip">
|
|
ext2tool.zip</A> written by <B>Claus Tondering</B>
|
|
that'll allow you to access your Linux files from DOS. It's a
|
|
bit shy in the looks department, but it seems reasonably sturdy and functional.
|
|
It supports the <B>ls, cd, cp, and cat</B> operations and includes a small
|
|
utility that helps identify your Linux partition number -- you'll need it to
|
|
set up the E2CWD variable.
|
|
|
|
<P>To set it up simply unzip it into a directory, I put it in its own \ext2tool directory for
|
|
the sake of tidiness, and then follow the guidelines in the README file. About the
|
|
only thing you'll need to do is set up the E2CWD variable:
|
|
|
|
<PRE>
|
|
[from the README]
|
|
|
|
Before you use the ext2 tools, you must set the environment variable
|
|
E2CWD using a statement similar to the following:
|
|
|
|
SET E2CWD=129:5
|
|
or
|
|
SET E2CWD=129:5:234
|
|
|
|
The three numbers after the equals sign are interpreted thus:
|
|
|
|
The first number (129 in the above example) identifies the physical
|
|
disk on which the ext2 file system is located. The number is used as
|
|
the second parameter to the DOS biosdisk() routine. Typical values
|
|
are:
|
|
0 for A: disk
|
|
1 for B: disk
|
|
128 for first hard disk
|
|
129 for second hard disk
|
|
|
|
(Your BIOS may use different values, especially if you have an SCSI
|
|
drive.)
|
|
|
|
The second number (5 in the above example) is the number of the disk
|
|
partition on which the ext2 file system is located. This number is
|
|
typically part of the Linux file name for the disk device. If, for
|
|
example, you are used to referring to the disk as /dev/hdb5 under
|
|
Linux, the partition number is 5. The E2PART program can help you
|
|
identify the partitions.
|
|
|
|
The third number is the inode number of the directory that is to be
|
|
your current working directory. If this number is omitted, 2 (the root
|
|
inode number) is used. If you don't know what an inode is, don't worry.
|
|
Just omit the final number from E2CWD.
|
|
</PRE>
|
|
|
|
<P>Since my Linux partition is on the first harddrive and on the /dev/hda6
|
|
partition I just entered:
|
|
|
|
<P>SET E2CWD=128:6
|
|
|
|
<P>in my c:\autoexec.bat file and everything worked fine.
|
|
|
|
<P>It's actually easier than it looks and, once you've set things up, it works
|
|
pretty well. As mentioned before, to get things <EM>back into Linux</EM> you'll
|
|
need to reboot and then copy it <EM>from</EM> from DOS since <B>ext2tool</B>
|
|
doesn't support writes. But then again, who'd want to spend much time in DOS
|
|
anyway... ;-)
|
|
|
|
<BR><BR>
|
|
<A HREF="#toc"><IMG ALIGN=BOTTOM SRC="./gx/toc.gif"></A>
|
|
<A HREF="mailto: fiskjm@ctrvax.vanderbilt.edu"><IMG ALIGN=BOTTOM SRC="./gx/sendmail.gif"></A>
|
|
<A HREF="./gazette_toc.html"><IMG ALIGN=BOTTOM SRC="./gx/index.gif"></A>
|
|
<A HREF="./linux/linux.html"><IMG ALIGN=BOTTOM SRC="./gx/home.gif"></A>
|
|
<BR><BR>
|
|
|
|
<HR>
|
|
|
|
<A NAME="kernel"><H2><IMG ALIGN=BOTTOM SRC="../gx/text.gif">Rolling your own kernel... it ain't that tough!</H2></A>
|
|
|
|
<P>For some people, the idea of compiling their own kernel gives them the willies and
|
|
wads their shorts in a knot.
|
|
|
|
<P>The good news is... it really ain't that tough.
|
|
|
|
<P>The reason is simple: the guys who spend their time hacking away on the kernel
|
|
have done a pretty good job of making everything work right. The actual task of
|
|
rolling your own kernel is <EM>technically</EM> quite simple. There is, however, one
|
|
small
|
|
|
|
<P><B>Caveat:</B> you have to know what you're doing.
|
|
|
|
<P>That said, let's see what you'll need to do in order to <EM>know what you're doing.</EM>
|
|
The heart of the matter is the step involving the " make config " procedure.
|
|
It's during this step that a script is run that asks you a series of questions about
|
|
what you want compiled into your kernel. Options include
|
|
|
|
<UL>
|
|
<LI>math coprocessor emulation
|
|
<LI>various harddrive drivers
|
|
<LI>filesystem support
|
|
<LI>networking support
|
|
<LI>support for cdroms, bus mice, sound cards
|
|
</UL>
|
|
|
|
and so forth. The script is intelligent enough to give you fairly reasonable
|
|
generic defaults. The thing is, <EM>the reason to roll your own kernel is to
|
|
provide it with only what YOU need for YOUR system.</EM>
|
|
|
|
<P>If you have a Logitech bus mouse, a GUS sound card, and run a PPP dial-up
|
|
connection, then you really don't need support for NFS, Ethernet cards, or
|
|
cdrom drives. If you answer one of the configuration questions incorrectly, it's
|
|
not that the kernel won't work... it will either have drivers included that you
|
|
can't use (kernel too large and takes up more memory), or it will lack some
|
|
option that you really need -- such as support for your bus mouse.
|
|
|
|
<P>So where do you go to learn?
|
|
|
|
<P>An excellent place to start is by reading <B>Brian Ward's</B> very helpful
|
|
<B>Kernel-HOWTO</B> which can be found, with an entire reference shelf of other
|
|
HOWTO's, on the
|
|
<A HREF="http://sunsite.unc.edu/mdw/linux.html#howtos">
|
|
Linux Documentation Project's HOWTO</A> section. Brian takes you through the
|
|
process step by step and explains what each of the options entails. Another helpful
|
|
place to find information and advice is in the
|
|
<A HREF="ftp://ftp.cc.gatech.edu/pub/linux/kernel/">Linux sunsite kernel</A>
|
|
directory. Several authors have written programs specifically to assist with
|
|
compiling your own kernel.
|
|
|
|
<P>And don't forget printed material. <B>Matt Welsh</B> and <B>Lar Kaufman</B>
|
|
have written an excellent book that needs to be on <EM>everyone's</EM> bookshelf
|
|
called <CITE>Running Linux</CITE> (Published by the folks at O'Reilly). At
|
|
$24.95 this is an absolute steal for over 500 pages of instruction, tips, tricks,
|
|
and step-by-step howto's. If you don't have it, get it.
|
|
|
|
<P>Once you've done your homework, the technical part is quite straight forward:
|
|
|
|
<OL>
|
|
<LI>Get a current copy of the Linux kernel sources from, e.g.,
|
|
<A HREF="ftp://ftp.cc.gatech.edu/pub/linux/kernel/v1.2/">GA Tech's Linux archive</A>.
|
|
<LI>Untar it into the /usr/src directory.
|
|
<LI>Create a symlink from /linux-1.2.x to /linux -- e.g., <CODE>ln -s /linux-1.2.x linux</CODE>
|
|
<LI>Now, cd to the /usr/src/linux directory and you're ready to start.
|
|
</OL>
|
|
|
|
At this point you simply enter:
|
|
|
|
<P><B>make mrproper ; make config ; make dep ; make clean ; make zImage</B>
|
|
|
|
<P>That's it. You'll see miles of script go whizzing by your screen and then a
|
|
series of questions will begin, asking you how you want your kernel configured --
|
|
you're in <B>make config</B>. Answer the questions and when it's done it will
|
|
set about compiling your new kernel.
|
|
|
|
<P>How long will it take?
|
|
<UL>
|
|
<LI>pentium/133 -- go to the bathroom but don't take too long.
|
|
<LI>pentium/66 -- run down and get a coke.
|
|
<LI>486DX2/66 -- run down and get a coke and flip through a magazine.
|
|
<LI>486SX/25 -- run down and get a coke, flip through a magazine, watch <EM>Cheers</EM>
|
|
reruns on the tube.
|
|
<LI>386DX40 -- run down and get a coke, flip through a magazine, watch <EM>Cheers</EM>
|
|
reruns on the tube, do a couple loads of wash.
|
|
<LI>386SX-16 -- run down and get a coke, flip through a magazine, watch <EM>Cheers</EM>
|
|
reruns on the tube, do a couple loads of wash, fly home to see your mom.
|
|
<LI>286 -- Uugh uugh, <EM>this dog don't hunt...</EM>
|
|
</UL>
|
|
|
|
Once the compile is done and you're through doing what you need to do, you can go
|
|
and pick up your shiny new kernel in:
|
|
|
|
<P>/usr/src/linux/arch/i386/boot
|
|
|
|
<P>It'll be called <CODE>zImage</CODE> and is usually at the bottom of your directory
|
|
listing. There you go! you've done it!
|
|
|
|
<P>Now I'll bet you want to try it out, eh? First, a couple <B>caveats!</B>
|
|
|
|
<P><B>Caveat #1</B>: make absolutely sure you have a working boot disk <EM>before</EM>
|
|
you do anything else.
|
|
|
|
<P><B>Caveat #2</B>: make sure the boot disk actually <EM>works!</EM>
|
|
|
|
<P><B>Caveat #3</B>: make a backup copy of your current working kernel image (usually,
|
|
/vmlinuz) and put it in a safe place.
|
|
|
|
<P>Now, rename you current kernel image -- e.g., <CODE>mv vmlinuz vmlinuz.bak</CODE>
|
|
and then copy the new zImage kernel to the root partition or wherever you put your
|
|
kernel images -- e.g., <CODE>cp zImage /vmlinuz.</CODE>
|
|
|
|
<P>You may need to <CODE>chmod 400 vmlinuz</CODE> to set the proper permissions and
|
|
then <B>don't forget to rerun LILO!</B> -- e.g., /sbin/lilo. Once you've done all
|
|
this, you're ready to reboot.
|
|
|
|
<P>Ok, go ahead... you can do the old <CODE>shutdown -r now</CODE> and keep your
|
|
fingers crossed!
|
|
|
|
<P><B>It didn't work??!!! Arrgghhh...!!</B> But don't fret, it's fixable. If your
|
|
system yurks up on your new kernel for some reason simply reboot using your boot
|
|
floppy and then copy your old kernel image, which you put in a safe place, back
|
|
into the root directory and <B>rerun LILO</B> -- e.g., /sbin/lilo.
|
|
|
|
<P>You should now have your old kernel image safely in place and can reboot your
|
|
system off the harddrive once again. But keep reading... we'll look at some ideas
|
|
for <EM>safely and easily test driving a new kernel</EM> in the next section.
|
|
|
|
<BR><BR>
|
|
<A HREF="#toc"><IMG ALIGN=BOTTOM SRC="./gx/toc.gif"></A>
|
|
<A HREF="mailto: fiskjm@ctrvax.vanderbilt.edu"><IMG ALIGN=BOTTOM SRC="./gx/sendmail.gif"></A>
|
|
<A HREF="./gazette_toc.html"><IMG ALIGN=BOTTOM SRC="./gx/index.gif"></A>
|
|
<A HREF="./linux/linux.html"><IMG ALIGN=BOTTOM SRC="./gx/home.gif"></A>
|
|
<BR><BR>
|
|
|
|
<HR>
|
|
|
|
<A NAME="testdrive"><H2><IMG ALIGN=BOTTOM SRC="../gx/text.gif">Test driving your kernel the <I>safe</I> way</H2></A>
|
|
|
|
<P>Now that you've had a run at compiling your own kernel, it's time to try it out
|
|
and see whether it actually works. Simply copying over your trusty old kernel is...
|
|
well, maybe just a bit brash, unless you <EM>really</EM> know what you're doing, or
|
|
you <EM>really</EM> are a thrill-seeker. If you're either of the above you can probably
|
|
stop reading here.
|
|
|
|
<P>For the rest of you, keep reading.
|
|
|
|
<P>There are two rather easy ways to try out your new kernel:
|
|
<UL>
|
|
<LI>making a boot disk from it
|
|
<LI>setting it up as a LILO boot option
|
|
</UL>
|
|
There are, to be sure, more sophisticated ways of testing out your new kernel...
|
|
but this ain't gurudom, it's simply what works. And either of these two methods
|
|
should give you the chance to try booting a new kernel without incurring too much
|
|
trouble in the process.
|
|
|
|
<P>To create a useable boot disk simply copy the <B>zImage</B> file that's in
|
|
your /usr/src/linux/arch/i386/boot/ directory to a floppy:
|
|
|
|
<PRE>
|
|
cp zImage /dev/fd0
|
|
</PRE>
|
|
to install it onto a disk in your first floppy drive. Keep in mind that this is
|
|
a <EM>bit</EM> of a kludge as it will wipe out any filesystem that exists on the
|
|
disk. It also goes without saying that you'll want to do this on a floppy that
|
|
doesn't have any important stuff on it. Copying this to the floppy that had your
|
|
327 page doctoral dissertation in LaTeX2e format on it is probably not a good
|
|
idea.
|
|
|
|
<P>Then, to try it out just reboot with the usual <B>shutdown -r now</B> and sit
|
|
back and enjoy. Keep an eye out for any error messages that may crop up during
|
|
the boot process. There is a utility you should be aware of if you're messing
|
|
around with kernels -- <B>rdev</B>, which allows you to set certain boot time
|
|
options for the kernel. These include such things as which partition to set up
|
|
as the root partition and as the swap partition, the root flags (read/write or
|
|
read only), the bootup videomode, the ramdisk size, and the byte offset to use.
|
|
You'll probably <B>not</B> need to adjust your kernel as it will likely point to
|
|
the correct root partition. If it doesn't, then you can enter:
|
|
|
|
<PRE>
|
|
rdev /dev/fd0 /dev/hda6
|
|
</PRE>
|
|
for example, if your root partition is, in fact, the /dev/hda6 partition.
|
|
You might, however, want to issue the command:
|
|
|
|
<PRE>
|
|
rdev -R /dev/fd0 1
|
|
</PRE>
|
|
This sets the root partition as <EM>read-only</EM> at boot time so that the
|
|
filesystem can be checked prior to being mounted. If you forget the exact
|
|
syntax of the command entering <CODE>rdev -h</CODE> will pop up a short
|
|
help screen to jog your memory.
|
|
|
|
<P>Now, once you know for sure that your new kernel works -- it actually let's you
|
|
mount your new CDROM, or dial up your PPP link -- you can go ahead and make a
|
|
back up copy of your trusty old kernel, put it in a safe place, and copy your
|
|
zImage file into your root directory. And <B>don't forget to run LILO</B> -- i.e.,
|
|
enter <CODE>/sbin/lilo</CODE> at the command prompt. If you don't, and you're
|
|
using LILO as your boot manager, you probably will not be able to boot your new
|
|
kernel, even if it works correctly.
|
|
|
|
<P>The other method is to simply add a stanza to your lilo.conf file that will
|
|
let you choose to boot either your usual kernel (often, /vmlinuz in your root
|
|
directory) or a new kernel you've just compiled.
|
|
|
|
<P>You'll need to edit your <B>/etc/lilo.conf</B> file. It might look something like:
|
|
|
|
<PRE>
|
|
# LILO configuration file
|
|
#
|
|
# Start LILO global section
|
|
append="sbpcd=0x230,SoundBlaster" # this is for my SoundBlaster CDROM
|
|
boot = /dev/hda6 # name of device where LILO installs itself
|
|
#compact # faster, but won't work on my system.
|
|
delay = 5 # wait time
|
|
vga = normal # force sane state
|
|
ramdisk = 0 # paranoia setting
|
|
# End LILO global section
|
|
#
|
|
# My normal Linux set-up -- boot from /vmlinuz
|
|
#
|
|
image = /vmlinuz # normal kernel in root directory
|
|
root = /dev/hda6 # my root partition
|
|
label = Linux # boot time label
|
|
read-only # Non-UMSDOS filesystems should be mounted read-only for checking
|
|
#
|
|
# Stanza to allow test driving of new kernel images
|
|
#
|
|
image = /usr/src/linux/arch/i386/boot/zImage
|
|
root = /dev/hda6
|
|
label = zImage # what I'll call the test kernel
|
|
read-only # Same as above
|
|
# Linux bootable partition config ends
|
|
</PRE>
|
|
|
|
Suffice it to say that configuring LILO, and actually getting it to work, can be
|
|
a bit hairy at times. This is one file you <EM>definitely</EM> want to have a boot
|
|
disk and a backup copy of before you blithely wander in where angels fear to tread.
|
|
Having done that, however, you should only have to make minor additions to your
|
|
/etc/lilo.conf file to get things working.
|
|
|
|
<P>What you'll need to add are primarily in the last 5 lines of the example above.
|
|
You'll need to add a stanza for the new test kernel. The <I>image</I> entry
|
|
indicates where the kernel image is located. In this case, it points to the
|
|
directory where the new kernel is found after you've compiled a kernel with the <B>make zImage</B> command.
|
|
Kinda tidy, eh?
|
|
|
|
<P>The only other required entry is the <EM>label</EM>, which is what LILO will
|
|
use when it asks you what you want to boot. The remainder of the entries, such
|
|
as <EM>root</EM> or <EM>vga</EM> can be left out and the options included at
|
|
compile time or set using <B>rdev</B> will be used. If you're a bit on the timid
|
|
side and don't want to hack away too much, you can safely enter just the
|
|
<EM>image</EM> and the <EM>label</EM> entries and things should work all right.
|
|
Last, but not least, <B>don't forget to rerun LILO</B> -- i.e., simply enter
|
|
<CODE>/sbin/lilo</CODE> at the command prompt and you should see something like:
|
|
|
|
<PRE>
|
|
Adding Linux *
|
|
Adding zImage
|
|
</PRE>
|
|
|
|
<P>Now, after you reboot, simply hold down the <B>Shift</B> key as LILO starts up
|
|
and it'll prompt you for which kernel you'd like to boot. Hitting the <B>Tab</B>
|
|
key will present you with a list of options. So... go ahead and enter <B>zImage</B>
|
|
and, if everything went as planned, <I>voila</I>! a new kernel. Using either of
|
|
these methods allows you to try booting a new kernel without disturbing your present
|
|
setup. If things don't work you can either remove your test boot floppy or tell
|
|
LILO to boot from your previous kernel.
|
|
|
|
<BR><BR>
|
|
<A HREF="#toc"><IMG ALIGN=BOTTOM SRC="./gx/toc.gif"></A>
|
|
<A HREF="mailto: fiskjm@ctrvax.vanderbilt.edu"><IMG ALIGN=BOTTOM SRC="./gx/sendmail.gif"></A>
|
|
<A HREF="./gazette_toc.html"><IMG ALIGN=BOTTOM SRC="./gx/index.gif"></A>
|
|
<A HREF="./linux/linux.html"><IMG ALIGN=BOTTOM SRC="./gx/home.gif"></A>
|
|
<BR><BR>
|
|
|
|
<HR>
|
|
|
|
<A NAME="thatsit"><H2><IMG ALIGN=BOTTOM SRC="../gx/text.gif">Well, that's it!</H2></A>
|
|
|
|
<P>Hope you enjoyed this premier issue of the <B>Linux Gazette</B>. I've tried to
|
|
make every effort to ensure that the information presented here is up to date and
|
|
correct. Please let me know if there are any glaring oversights or errors in this.
|
|
Also, if you have suggestions, comments, or critisms let me know.
|
|
|
|
<P>If there's any interest in this, I'd be happy to keep writing new editions.
|
|
|
|
<BR>
|
|
|
|
<HR>
|
|
|
|
<H4>Got any <I>great</I> ideas for improvements! Send your
|
|
<A HREF="mailto:fiskjm@ctrvax.vanderbilt.edu">comments, criticisms, suggestions, and ideas.</H4>
|
|
|
|
<BR>
|
|
<A HREF="linux/linux.html"><IMG ALIGN=BOTTOM SRC="../gx/back.gif"> Back up to Linux HomeBoy WebPage</A> <BR>
|
|
<BR>
|
|
|
|
<I>This page written and maintained by:</I><BR>
|
|
<ADDRESS>
|
|
<A HREF="jmf.html">John M. Fisk</A> at <A HREF="mailto:fiskjm@ctrvax.vanderbilt.edu">
|
|
fiskjm@ctrvax.vanderbilt.edu</A>
|
|
</ADDRESS>
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