[Beowulf] kdump / kexec to optain crash dumps from randomly crashing nodes.

[Paolo Supino]

Hi Rahul

 Did you try to redirect console to a serial port? If a system crashes
and all console messages (including kernel) will be sent to the serial
console that will keep displaying the messages it received until the
system is power cycled ...





--
ttyl
Paolo



Rahul Nabar wrote:
> On my Centos system I installed kexec/kdump to investigate the cause of
> some random system-crashes by getting access to a crash-dump. I installed
> the rpm for kexec and then made the change to grub.conf that reserves the
> additional memory for the new kernel.
> 
> Also configured kdump.conf. I start the kexec service.and then I tried to
> simulate a crash by echo c to sysrq-trigger.
> 
> The system does crash and then after a while reboots itself. But I see no
> vmcore when it coms back up. /var/crash is empty. This is when I tried to
> write to local drive.
> 
> I also tried a nfs write but then still no success.
> 
> Any idea what could be missing in my steps? Or any other debug
> suggestions? Any other kdump users on Beowulf?
>