If you plan to use a virtual disk in Windows Server Failover Clustering (WSFC) configurations, your VMFS6 datastore must support clustered virtual disks. Use the vSphere Client to enable the clustered disk support.

For information on the use of clustered virtual disks in VM clusters, see the Setup for Windows Server Failover Clustering documentation.


Follow these guidelines when you use a datastore for clustered virtual disks:
  • The storage array must support the ATS, Write Exclusive – All Registrant (WEAR) SCSI-3 reservation type.
  • ESXi supports only Fibre Channel arrays for this type of configurations.
  • Only VMFS6 datastores support clustered disks. The datastores you use cannot be expanded or span multiple extents.
  • Storage devices must be claimed by the NMP. ESXi does not support third-party plug-ins (MPPs) in the clustered virtual disk configurations.
  • Make sure that the virtual disks you use for clustering are in the Thick Provision Eager Zeroed format.


  1. In the vSphere Client, navigate to the datastore.
  2. Click the Configure tab, and click General.
  3. Under Datastore Capabilities, click one of the following options next to the Clustered VMDK item.
    Option Description
    Enable To enable support for clustered virtual disks on the datastore. After you enable the support, you can place the clustered virtual disks on this VMFS datastore.
    Disable To disable the support. Before disabling, make sure to power off all virtual machines with the clustered virtual disks.
  4. Confirm your configuration.