You can mount a VMFS datastore copy without changing its signature if the original is not mounted.
For example, you can 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 can mount the datastore copy and power on the virtual machines at the secondary site.
Important: You can mount a VMFS datastore only if it does not conflict with an already mounted VMFS datastore that has the same UUID.
When you mount the VMFS datastore, ESXi allows both read and write operations to the datastore that resides on the LUN copy. The LUN copy must be writable. The datastore mounts are persistent and valid across system reboots.
You can mount a datastore with ESXCLI or with vicfg-volume. See Mount a Datastore with ESXCLI or Mount a Datastore with vicfg-volume.