Jason's Tips

 in
Tips and factoids from Jason Schumaker.
Link of the Month:

Learn the hardware and software procedures for making MP3 and Linux get along. www.ssc.com/mirrors/LDP/HOWTO/MP3-HOWTO.html

Rebuilding Your Kernel

When rebuilding kernels, make a backup of the last one that worked, and include a stanza in your /etc/lilo.conf to allow booting the working kernel. For example, with kernels found in /boot/vmlinuz and last known working kernel in /boot/vmlinuz.works, /etc/lilo.conf might look like:

boot=/dev/hda<\n>
install=/boot/boot.b
map=/boot/map
vga=normal
timeout=200
prompt
read-only
image=/boot/vmlinuz
root=/dev/hda1
label=Linux
read-only
password=Vogons
restricted
image=/boot/vmlinuz.works
root=/dev/hda1
label=Itworks
read-only
password=Vogons
restricted

this will present a LILO prompt and wait 20 seconds for instructions as to which kernel to boot. The user may type

Linux
or
Itworks
to select most recent build or most recent known good kernel. The “password” and “restricted” parameters prevent entry of additional boot parameters which might compromise security, without entry of the correct password. Make /etc/lilo.conf read/write to root, no permission to group or other.

Once a kernel is known to work, as root:

cp /boot/vmlinuz /boot/vmlinuz.works<\n>
lilo

Dan Wilder

Hardware Tips

If you are using Linux and your system keeps crashing suspect the hardware, unless you are running some bleeding edge development kernel.

First, check the memory. There is a great program for memory check called memtest86 (http://reality.sgi.com/cbrady_denver/memtest86/).

The memtest program is an x86 boot sector. You can put it on a floppy and boot the suspect computer to memtest from a floppy drive. Or, my favorite is to load memtest from lilo as an operating system. Use an image clause in your lilo.conf file like this:

image=/vmlinuz          #Your Linux kernel<\n>
        label=Linux
        read-only
image=/memtest          #Your copy of memtest
        label=Memtest
Have You Checked Your CPU Lately?

Sometimes CPU's just don't perform well at their rated speeds. You run into weird things like segmentation faults while using ls! Under clock your CPU. A good way to give your CPU a test is to run setiathome on your machine. See: http://setiathome.ssl.berkeley.edu/. This puts your CPU to work doing lots of fast Fourier transforms. Don't forget to join the Linux Journal setiathome group.

Still having problems? Lower the motherboard bus speed by a hair. If you see or smell smoke, shut off the power.

—Rory Krause

VI TIP: Converting DOS files to Linux/UNIX

It happens often: an author sends a file created in DOS, which adds ^M throughout the text. To globally remove all ^Ms from a DOS file I use one of the following two options:

dos2unix <filename>
bni:or
:%s/^M//

The ^M is produced by typing CTRL-V, then CTRL-M. Use them both—for a bit of variety!

—jason schumaker

Not a Rhetorical Question

“Linux happened without the help of deep pockets—how can we keep the magic?”

—Bruce Pehrens, posing a question to Michael Dell at LinuxWorld.

“Linux has to change the world more than the world needs to change Linux. Because IT sucks.”

—Don Marti

Looking for a news site similar to Slashdot? Try: http://www.kuro5hin.org/. Reader's vote articles on or off!

HIGH-TECH NEWSFLASH

Palm will soon be unveiling a new version of the Palm Vx—the Claudia Schiffer model! Try http://www.claudiaschiffer.com/ for more details.

QUOTE

“If Jesus Christ would have lived long enough, he would have repeated himself, too.”

—Kurt Vonnegut Jr.

______________________

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