https://bugzilla.redhat.com/show_bug.cgi?id=905282https://bugzilla.redhat.com/show_bug.cgi?id=967494
When lock failure is detected by sanlock, our sanlock_helper kill script
will try to restart (shutdown followed by start) the affected domain
when RESTART action is configured for it. While shutting down kills QEMU
and removes all its leases (which is what sanlock wants to happen),
trying to start it again just hangs because libvirt tries reacquire the
locks in the failed lock space. Hence, this action cannot be supported
by sanlock driver.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=905280https://bugzilla.redhat.com/show_bug.cgi?id=967493
Sanlock expects that the configured kill script either kills the PID on
lock failure or removes all locks the PID owns. If none of the two
options happen, sanlock will reboot the host. Although IGNORE action is
supposed to ignore the request to kill the PID or remove all leases,
it's certainly not designed to cause the host to be rebooted. That said,
IGNORE action is incompatible with sanlock and should be forbidden by
libvirt.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
While the changes to sanlock driver should be stable, the actual
implementation of sanlock_helper is supposed to be replaced in the
future. However, before we can implement a better sanlock_helper, we
need an administrative interface to libvirtd so that the helper can just
pass a "leases lost" event to the particular libvirt driver and
everything else will be taken care of internally. This approach will
also allow libvirt to pass such event to applications and use
appropriate reasons when changing domain states.
The temporary implementation handles all actions directly by calling
appropriate libvirt APIs (which among other things means that it needs
to know the credentials required to connect to libvirtd).
