Migrating Clustered VMs Between Data Stores

If you've ever tried to migrate a VM that's got shared drives (generally a cluster member) between data stores, you'll have found that you can't!

You could move the files physically (which would work) but you would lose any thin provisioning.

So - shut down the server (since it's part of a cluster, that shouldn't be a problem). Now make a note of all of the shared drives, their location and the SCSI address they are connected to.

Remove them (but don't delete, obviously). Now you can migrate the machine to another data store and choose whether to thin provision or not.

Add them back in once that's done, making sure you match the SCSI IDs.

All done.