[ovirt-users] smoothly update Compatibility Version

Hi all, I would like to bring our hosts up to 3.5 compatibility version. Currently we have one host at Compatibility Version 3.5(NonOperational) and a few others at 3.3 in the cluster/datacenter. I am guessing that if I change Cluster Compatibility Mode to 3.5 all hosts not 3.5 will go into NonOperational state - the VM's will try to migrate (likely fail) and/or stop. VM's will need to be 'rebooted' to the Operational host (the only one upgraded so far). Does the Datacenter Compatibility Mode need to be updated for VM's to work again? What are people doing at this upgrading step to minimize vm downtime? Thanks, Justin