/var/log/messages doesn't have crash info when kernel gets panic/oops/crash

[Eric W. Biederman]

Dharmosoth Seetharam <dseetharam at inbox.com> writes:

> Hi,
>
> I have experimented few things and results are below.
>
> Case 1) echo 0 > /proc/sys/kernel/panic_on_oops
>         When BUG/oops occurred it is able to log the diagnostics to /var/log/messages
>         and then continue(not switching to dump-saving kernel).
>
>         What I am looking is - I want both the things to be happen.
>         that is - it should log the appropriate messages in /var/log/messsages and
>         should be able to take kernel dump.

You can't have it.  Sorry.
Keeping user space alive is something that simply can not be done reliably.

> Please advice me, What we can do to achieve those things.

The only scenario I see possible is to take the dump.  Use
makedumpfile or the crash log command to extract the kernel messages
and put them in the /var/log/messages.

Eric