SAN Mode Restores Fail for Clustered VMDK Datastores

You cannot write to VMware clustered VMDK datastores in VMFS6 because of SCSI reservations on the physical LUN, so restore operations cannot run.

Symptoms

If Clustered VMDK is set to Enabled under vSphere Client > Configure > Datastore Capabilities, the 6.7 VDDK might hang on a Windows proxy, or display an error on a Linux proxy. However, the 7.0 VDDK rejects SAN-mode writes to both datastores with Clustered VMDK enabled and datastores with Clustered VMDK disabled.

Causes

This is caused by code in the 7.0 VDDK release.

Resolution

To resolve this issue, you can downgrade to VDDK 6.7 and disable Clustered VMDK. This allows SAN-mode restore operations to run.

1. Open the Registry Editor and go to  Installation Path/CommVaultSystems/Galaxy/Instance001/VirtualServer.
2. Under Properties, add nVDDKVersionPath 673.
3. Restart Commvault services.
4. Run a SAN-mode restore to the datastore where Clustered VMDK is disabled.