If a VMFS datastore is ATS-only compatible, you can upgrade its locking mechanism from ATS+SCSI to ATS-only.

Most datastores that do not span multiple extents are eligible for an online upgrade. While you perform the online upgrade on one of the ESXi hosts, other hosts can continue using the datastore. The online upgrade completes only after all hosts have closed the datastore.


If you plan to complete the upgrade of the locking mechanism by putting the datastore into maintenance mode, disable Storage DRS. This prerequisite applies only to an online upgrade.


  1. Perform an upgrade of the locking mechanism by running the following command:
    esxcli storage vmfs lockmode set -a|--ats -l|--volume-label= VMFS label -u|--volume-uuid= VMFS UUID.
  2. For an online upgrade, perform additional steps.
    1. Close the datastore on all hosts that have access to the datastore, so that the hosts can recognize the change.
      You can use one of the following methods:
      • Unmount and mount the datastore.
      • Put the datastore into maintenance mode and exit maintenance mode.
    2. Verify that the Locking Mode status for the datastore changed to ATS-only by running:
      esxcli storage vmfs lockmode list
    3. If the Locking Mode displays any other status, for example ATS UPGRADE PENDING, check which host has not yet processed the upgrade by running:
      esxcli storage vmfs host list