You can configure an automated dump for a virtual server if a kernel panic occurs on the guest.
Before you begin
If kdump is set up for the KVM guest that runs on the
virtual server, kdump takes priority and a dump is created on
the KVM host only if kdump fails. Use the following procedure
as an alternative or as a backup for kdump.
Procedure
- Ensure that the domain configuration-XML of the virtual server includes the on_crash element.
If
needed, add the element as a child element of the domain element.
- Specify
coredump-destroy or coredump-restart as the
text content of the on_crash element.
- coredump-destroy
- To stop the virtual server and release all resources when
the dump process is completed.
- coredump-restart
- To restart the virtual server when the dump process is
completed. This setting can be useful to automatically restore operations, but incurs the danger of
restart and crash cycles with dumps accumulating on the KVM host.
Results
When a kernel panic occurs on the guest, a core dump is written to
/var/lib/libvirt/qemu/dump on the KVM host. Depending on your specification for the on_crash element, the virtual server is restarted or all resources of the virtual server are released.
Example
<domain type="kvm">
...
<on_crash>coredump-destroy</on_crash>
...
</domain>