Rebooting a single VM in a 2-VM node ExaCC cluster

There appears to be plenty of documentation on rebooting compute, storage and db nodes and clusters, but I have not yet been able to isolate what is needed apart from 'shutdown -r 0' to reboot a single VM in a 2-VM node ExaCC cluster.

We have VM1 and VM2. VM2 has changes we are testing and want to see if they will 'stick' after a reboot. We do not want to affect VM1 at all. How do we go about rebooting VM2?

If I execute 'shutdown -r 0' of course the LInux kernel will proceed with the init process and boot the box. However, are there other commands that should be executed prior to executing the shutdown command so as to alert the DB and Grid services that we're going down, etc?