How can I get a Kernel Core Dump

We're trying to debug a kernel panic/oops on Ubuntu 10.04. The stacktrace isn't quite enough for us. How can we configure the system to spit out a core dump and where can we find it after the crash?

There is a lot of information on how to get a user-mode core dump, but very little (or old) information on getting a kernel core dump.

LKCD exists, but looks as though it hasn't been updated since 2002.

From ubuntu Tom

• Installing the linux-crashdump package will install the kexec tools and set up grub to pass the needed kernel options to have the crashdump kernel available.

  This should automatically catch kernel crashes. For non-crash kernel problems such as an oops you should be able to use the magic sysrq key's c command to kexec the crashdump kernel and get a dump.

  You may also want to enable apport to have the dump nicely processed into a crash report for submission to Launchpad or for local retracing. To do that you need to edit /etc/default/apport.

  From RAOF