If you do not need to resignature a VMFS datastore copy, you can mount it without changing its signature.

You can keep the signature if, for example, you maintain synchronized copies of virtual machines at a secondary site as part of a disaster recovery plan. In the event of a disaster at the primary site, you mount the datastore copy and power on the virtual machines at the secondary site.

Important: You can mount a VMFS datastore copy only if it does not collide with the original VMFS datastore that has the same UUID. To mount the copy, the original VMFS datastore has to be offline.

When you mount the VMFS datastore, ESXi allows both reads and writes to the datastore residing on the LUN copy. The LUN copy must be writable. The datastore mounts are persistent and valid across system reboots.


Launch the vSphere Client and log in to a vCenter Server system.

Before you mount a VMFS datastore, perform a storage rescan on your host so that it updates its view of LUNs presented to it.


  1. Log in to the vSphere Client and select the server from the inventory panel.
  2. Click the Configuration tab and click Storage in the Hardware panel.
  3. Click Add Storage.
  4. Select the Disk/LUN storage type and click Next.
  5. From the list of LUNs, select the LUN that has a datastore name displayed in the VMFS Label column and click Next.
    The name present in the VMFS Label column indicates that the LUN is a copy that contains a copy of an existing VMFS datastore.
  6. Under Mount Options, select Keep Existing Signature.
  7. In the Ready to Complete page, review the datastore configuration information and click Finish.

What to do next

If you later want to resignature the mounted datastore, you must unmount it first.