Automatic dumping

You can configure a dump device that is automatically used when a kernel panic occurs.

If you set up kdump, a kernel panic or PSW restart automatically triggers a dump. You can also use dumpconf to set up automatic dumping for standalone tools, or for your backup dump solution.

See dumpconf - Configure panic or PSW restart action for how to set up dumpconf. Once you have set up the automation, you can cause a kernel panic to test the configuration.

Testing automatic dump-on-panic

Edit online

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.

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	`c`
Writing to procfs	`echo c > /proc/sysrq-trigger`

Note:

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. If kdump is set up correctly, the kdump kernel is booted, the dump is created (the default directory is /var/carsh), and your production system is rebooted.