Writing oops-messages to floppy or disk

Writing oops-messages to floppy or disk

[Erik Tews]

Hi

Some days ago, I had the problem that the isdn-router in our school
crashed (was a problem with mppp, I am currently talking with the
isdn-guys). I had a oops-message on my screen. My kernel has had
magic-sysrq-support. So I needed this message somewhere to give it so
ksymoops. The only solution I had was typing it into my laptop by hand.

So I would like to know if there is a solution to tell the kernel to
write the current screen (or the oops-message) to floppy (bypassing the
filesystem, just raw write, reading it back with dd if=/dev/fd0, of=-)
The only option I have with ksymoops is syncing my filesystems, but most
time, the kernel freezes before syslogd is able to write it to the
filesystem. Or an other solution to get the message to resistant memory.

Typing the message by hand into my laptop is a bad thing, because it
takes a lot of time, and during this time, the system is down.

Re: Writing oops-messages to floppy or disk

[Andreas Dilger]

On Aug 22, 2001  16:43 +0200, Erik Tews wrote:
> So I would like to know if there is a solution to tell the kernel to
> write the current screen (or the oops-message) to floppy (bypassing the
> filesystem, just raw write, reading it back with dd if=/dev/fd0, of=-)

There is a patch that does this (for 2.2, and 2.4 I think) called kmsgdump.
It allows you to dump oops messages to a floppy or to a printer.  It also
has a tool to make a special dump floppy which just lets the boot "pass
through" the floppy and boot from the next BIOS device.  This allows you
to leave the dump floppy in the drive all the time, in case of an oops,
but also allows the system to continue booting afterwards.

I don't know where the current kmsgdump patches are, but Google should
find them.

Cheers, Andreas
-- 
Andreas Dilger
http://sourceforge.net/projects/ext2resize/
http://www-mddsp.enel.ucalgary.ca/People/adilger/