Thu May 17 10:51:33 EDT 2012

NFS on VMs

When mounting NFS exports on a VM with VM host as NFS client, care
needs to be taken to break the following loop:

- VM needs to shut down before HOST
- HOST needs to unmount VM shares before VM shutdown

Best way to go:
- stop automounter on host
- halt VM
- halt host or restart automounter

There seem to be several tricks around this, but from my experience it
doesn't always work to recover from this.  Closing the mount before
shutting down the NFS server seems to be the only reliable way.

Just rebooting the VM when NFS mounts are active is OK.  NFS mount on
client will just block until server comes up again.

Remaining question: how to properly halt a raw KVM machine?