I am in need of moving a single hard disk on a VM to a different datastore cluster. The Move-HardDisk command works great to move the hard disk to a separate datastore but does not appear to support moving to a different datastore cluster. Is there way to do this?
Not with a PowerCLI cmdlet I'm afraid.
But you can call the vSphere API methods directly.
First you need to use the RecommendDatastores method to find the datastore recommendation for a specific vDisk.
Then you use that result in the RelocateVM method to actually move the vDisk
The mentioned thread contains a sample script, it moves all vDisks of a VM to the datastorecluster.
But you can easily adapt the Where-clause to select a specific vDisk