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Re: [OCLUG-Tech] Finding a Linux Kernel Panic

Bart Trojanowski wrote:
: Another is a netconsole.  This is similar to syslog, in that it logs
: simple text messages from the kernel over a UDP "connection".  To
: configure it you simply have to run:

Netconsole seems promising, and would provide at least the proof I'm looking
for.

: Another way is to setup kdump, which will create kernel core files on
: the disk.  See if your distribution has the kexec-tools package.

It does.  I'd found LKCD, but Novell moved from LKCD to kexec/kdump in the
10.x line (and continues in that vein for 11.x).  This is far and above the
most promising option for actually diagnosing the kernel crash, though
perhaps more complicated than netconsole to get going.

: Yet another way is to use netdump, but I think this is mainly maintained
: by RedHat.  netdump will send a core file over the network to a netdump
: server.  It's a bit of a pain.

kdump can actually do the same, it turns out, which is likely the route I'll
be going.

: Finally there is kgdb.  This allows you to connect a debugger to a
: running kernel.  kgdb can work over serial (kgdboc) or ethernet
: (module kgdboe).  Unfortunately, the kgdboe is not available in mainline
: kernels, and I don't know if SuSE ships it.

That's good to know as well, though I'm surprised the panic doesn't give you
the option to drop into a kgdb prompt directly.  I'm not sure if kgdb will
pan out for us, but we rarely need to diagnose a crash as soon as it
happened -- so long as we have a vmcore to analyze later, that's sufficient.

Thanks for the help!  At least I have a clue as to what to do now.

  - Damian