Testing automatic dump-on-panic

Cause a kernel panic to confirm that your dump configuration is set up to automatically create a dump if a kernel panic occurs.

Before you begin

  • You need a Linux® instance with active magic sysrequest functions.
  • For KVM guests, you can use the virsh inject-nmi on the KVM host instead of the magic sysrequest function (see KVM guest example).

Procedure

Crash the kernel with a forced kernel panic.
If your method for triggering the magic sysrequest function is: Enter:
A command on the 3270 terminal or line-mode terminal on the HMC ^-c
A command on the hvc0 terminal device Crtl+oc
Writing to procfs echo c > /proc/sysrq-trigger
Note: Crtl+o means pressing o while holding down the control key.
For more details about the magic sysrequest functions, see the documentation in the Linux source tree at /usr/src/linux/Documentation/sysrq.txt (requires installation of the kernel-source package).

Results

The production system crashes and if your automatic dump is set up correctly, the dump process is triggered. In particular, if kdump is set up correctly, the kdump kernel is booted, the dump is created (the default directory is /var/crash/), and your production system is rebooted.