libvirt users - Aug 2020 - Re: Distinguishing between host and guest initiated VM shutdown

Hi,

we have a problem in oVirt that highly available VMs don't restart after
host poweroff because Vdsm identifies the case as a user initiated
shutdown (https://bugzilla.redhat.com/1800966).

When poweroff is run on the host, libvirt-guests service takes an
action.  `virsh shutdown' is run on the VM, the guest OS is shut down
cleanly and libvirt reports a shutdown event with
VIR_DOMAIN_EVENT_SHUTDOWN_GUEST detail.  Although it is a host initiated
shutdown actually.

Does libvirt provide any means to distinguish this case from a regular
user shutdown?

Thanks,
Milan

On Wed, Aug 26, 2020 at 10:35:22PM +0200, Milan Zamazal
wrote:
> Hi,
> 
> we have a problem in oVirt that highly available VMs don't restart
after
> host poweroff because Vdsm identifies the case as a user initiated
> shutdown (https://bugzilla.redhat.com/1800966).
> 
> When poweroff is run on the host, libvirt-guests service takes an
> action.
If oVirt is initiating a graceful host shutdown, then surely it already
knows what VMs it has running on the host at that time, and so has enough
info to restart them later.
>            `virsh shutdown' is run on the VM, the guest OS is shut down
> cleanly and libvirt reports a shutdown event with
> VIR_DOMAIN_EVENT_SHUTDOWN_GUEST detail.  Although it is a host initiated
> shutdown actually.
> 
> Does libvirt provide any means to distinguish this case from a regular
> user shutdown?
A "virsh shutdown" merely triggers a request to the guest OS to start
a guest initiated shutdown. As such it is indistinguishable from an
administrator initiating the same thing inside the guest.

Regards,
Daniel
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"Daniel P. Berrange" <dan@berrange.com> writes:
> On Wed, Aug 26, 2020 at 10:35:22PM +0200, Milan Zamazal wrote:
>> Hi,
>> 
>
>> we have a problem in oVirt that highly available VMs don't restart
after
>> host poweroff because Vdsm identifies the case as a user initiated
>> shutdown (https://bugzilla.redhat.com/1800966).
>> 
>> When poweroff is run on the host, libvirt-guests service takes an
>> action.
>
> If oVirt is initiating a graceful host shutdown, 
I meant host shutdown not initiated by oVirt.
> then surely it already knows what VMs it has running on the host at
> that time, and so has enough info to restart them later.
>
>>            `virsh shutdown' is run on the VM, the guest OS is shut
down
>> cleanly and libvirt reports a shutdown event with
>> VIR_DOMAIN_EVENT_SHUTDOWN_GUEST detail.  Although it is a host
initiated
>> shutdown actually.
>> 
>> Does libvirt provide any means to distinguish this case from a regular
>> user shutdown?
>
> A "virsh shutdown" merely triggers a request to the guest OS to
start
> a guest initiated shutdown. As such it is indistinguishable from an
> administrator initiating the same thing inside the guest.
OK, so we will have to check on VM shutdown whether the host is in
shutdown or not ourselves.

Thank you for clarification,
Milan