kernel panic on Fedora 8 - a serious bug!

[D. Hugh Redelmeier]

| Date: Thu, 21 Feb 2008 13:17:09 +0100 (CET)

| title Fedora 8 (2.6.23.15)
|         root (hd0,0)
|         kernel /vmlinuz-2.6.23.15 ro root=/dev/md1 console=tty0
| console=ttyS0,115200
|         initrd /initrd-2.6.23.15.img
| 
| So the kernel is also pumping the information via the first com port.
| Start minicom at the other machine, select right setting for baudrate
| 115200 and voila. You will see output, even when it crashes.
| 
| This is really then the only way to see if the kernel is really crashing
| at something. I have the luxery here to have console servers with buffers.
| So if a machine crashes, I can read the buffer of the output, and see what
| happened.

The kdump tool is also good for this.  It will give you a dump that
you can analyze with crash(8).  It does not require a serial port
(getting scarce these days).

The trouble is that this stuff is not well documented.  Not that many
people use it, so you can bump into problems.

See:

http://fedoraproject.org/wiki/FC6KdumpKexecHowTo
  This is for FC6.  I don't know of a newer one.

crash(8) is always playing catch-up with the kernel releases.  The update
repositories don't seem to have new enough versions.  You are best off
getting a source RPM from the author's web site and building it.

I have posted a few messges to this list intended to help folks with
this tool.  Here are a couple:

http://www.redhat.com/archives/rhl-list/2007-June/msg03592.html
http://www.redhat.com/archives/fedora-list/2007-December/msg02780.html