I'm running Ubuntu Server 14.04 on a machine that is experiencing random crashes under load. The server doesn't restart independently, but it becomes inaccessible via ssh or direct KVM connection.
I suspect CPU issues, but I'm looking for a smoking gun, so I'm following the instructions here:
However, no logfile appears in
/var/crash after either a natural or induced crash.
(I induced a crash between each change described here, with no change.)
Everything went smoothly until I got to this step:
$ cat /sys/kernel/kexec_crash_loaded 0
Expected output was 1. A bit of digging led me to
/etc/default/kdump-tools, where I set
USE_KDUMP=1. When that didn't work, I added
KDUMP_SYSCTL="kernel.panic=60 kernel.panic_on_oops=1" based on the sysctl documentation. Still no joy, so I modified the param directly with
sysctl -w kernel.panic=60 to supposedly add extra time for kdump to do its thing.
In every case, I would run:
echo c | sudo tee /proc/sysrq-trigger
The computer would crash and reboot as expected, but all I'd see is this:
$ ls /var/crash kexec_cmd
/var/log/kern.log contains only log entries from boot, not from the crashes. (Not sure if this is expected, but I thought I'd mention it anyway.)
Is there something wrong with my configuration?