Thoughts on VM fence infrastructure

[Felipe Franciosi]

Heyall,

We have a use case where a host should self-fence (and all VMs should
die) if it doesn't hear back from a heartbeat within a certain time
period. Lots of ideas were floated around where libvirt could take
care of killing VMs or a separate service could do it. The concern
with those is that various failures could lead to _those_ services
being unavailable and the fencing wouldn't be enforced as it should.

Ultimately, it feels like Qemu should be responsible for this
heartbeat and exit (or execute a custom callback) on timeout.

Does something already exist for this purpose which could be used?
Would a generic Qemu-fencing infrastructure be something of interest?

Cheers,
F.