How to Troubleshoot Kernel Panic?

Doug Vitale · 10-11-2007, 07:34 PM

I'm using Kubuntu 7.04 on a new Dell XPS PC. Occasionally after selecting Kubuntu from the grub screen, a kernel panic will occur resulting in a screen full of error codes and such.

How can I configure Kubuntu to create a dump log so this panic can be troubleshot? There are simply too many characters on the screen to copy down onto paper and type into a post here. Thanks very much.

jailbait · 10-11-2007, 07:44 PM

Quote:

Originally Posted by Doug Vitale

I'm using Kubuntu 7.04 on a new Dell XPS PC. Occasionally after selecting Kubuntu from the grub screen, a kernel panic will occur resulting in a screen full of error codes and such.

How can I configure Kubuntu to create a dump log so this panic can be troubleshot? There are simply too many characters on the screen to copy down onto paper and type into a post here. Thanks very much.

It depends on how far you get into boot before you have the kernel panic. After a certain point kernel messages are logged and you can print the messages using the dmesg command:

dmesg > /tmp/kernel.panic.txt

See:

man dmesg

-------------------
Steve Stites

Whoops, the log will be overwritten by the next boot so you should boot a live CD and then retrieve the kernel log by running dmesg against the old kernel log on your hard drive.

sundialsvcs · 10-11-2007, 10:12 PM

The most common kernel-panic that occurs at-or-near boot time is that init dies ... which is reported as "attempted to kill init." (By definition, init is not allowed to die.)

There are various root causes, which will be found in messages which shortly precede the actual fall-over-and-die. Unfortuantely it's not easy to categorize those causes.

Doug Vitale · 10-15-2007, 07:39 PM

Quote:

Originally Posted by jailbait

It depends on how far you get into boot before you have the kernel panic. After a certain point kernel messages are logged and you can print the messages using the dmesg command:

dmesg > /tmp/kernel.panic.txt

Whoops, the log will be overwritten by the next boot so you should boot a live CD and then retrieve the kernel log by running dmesg against the old kernel log on your hard drive.

I got one of those panics so I rebooted with an Ubuntu installation disc. However, I don't know how to access my usual Ubuntu partition (/dev/sda4) after booting to Live CD mode. When I run "mount /dev/sda4" I get the message: "mount: can't find /dev/sda4 in /etc/fstab or /etc/mtab".

How should I proceed from here? Thanks.

jailbait · 10-16-2007, 12:26 PM

Quote:

Originally Posted by Doug Vitale

I got one of those panics so I rebooted with an Ubuntu installation disc. However, I don't know how to access my usual Ubuntu partition (/dev/sda4) after booting to Live CD mode. When I run "mount /dev/sda4" I get the message: "mount: can't find /dev/sda4 in /etc/fstab or /etc/mtab".

How should I proceed from here? Thanks.

Assuming that your root filesystem is ext3

mkdir /fixit
mount -t ext3 /dev/sda4 /fixit
chroot /fixit
dmesg

-----------------
Steve Stites

AceofSpades19 · 10-16-2007, 07:33 PM

In the ubuntu livecd, just go to Places>Computer and on the side there should be something like
30 gb volume, just double click on that