During VM start, if VM already exists and CS finds a matching disk in storage for each of the existing disk then the VM is reconfigured with VM's existing disk information. This existing disk information for a VM is got from vCenter.
CS checks if a matching disk exists in storage by checking if there is a disk in storage whose name atleast partially matches with the name of the existing disk.
Post 4.1, Volume path has been changed to ROOT-<instanceId> from ROOT-<instanceId>-<volumeId>. Hence in case of an upgraded setup (pre 4.1 to 4.2) during search for an existing disk in storage even though ROOT-<instanceId>-<volumeId> has been deleted, CS does a postive match of the old existing disk because of the partial match with the new disk ROOT-<instanceId> that exists in storage. And so when VM is being powered on by vCenter it looks for ROOT-<instanceId>-<volumeId> and fails to power on.
Solution - While looking for a VM's matching disk in storage, instead of checking if a disk with a partial match exists check if a disk with the exact name exists.
Likitha Shetty
Alex Huang
Kelven Yang