Moving unused disks lock VM ?

I am testing a production workflow we are attempting to build using PVE and am a bit confused...

Part of the workflow is to take advantage of PVE to manage migration of virtual disks between storage tiers. However, it appears our workflow is dead in the water because PVE will not allow us to snapshot a VM if unattached VDs are being migrated. Can anyone explain why this is the case ? PVE doesn't even offer the ability to snapshot unattached VDs, so why is the VM locked for this operation...

Read more