6.5.1

Table Of Contents
ESXi can detect the VMFS datastore copy and display it in the vSphere Web Client. You can mount the
datastore copy with its original UUID or change the UUID. The process of changing the UUID is called the
datastore resignaturing.
Whether you select resignaturing or mounting without resignaturing depends on how the LUNs are
masked in the storage environment. If your hosts can see both copies of the LUN, then resignaturing is
the optimal method.
Keep Existing Datastore Signature
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.
Prerequisites
n
Perform a storage rescan on your host to update the view of storage devices presented to the host.
n
Unmount the original VMFS datastore that has the same UUID as the copy you plan to mount. You
can mount the VMFS datastore copy only if it does not collide with the original VMFS datastore.
Procedure
1 In the vSphere Web Client navigator, select Global Inventory Lists > Datastores.
2 Click the New Datastore icon.
3 Enter the datastore name and if necessary, select the placement location for the datastore.
4 Select VMFS as the datastore type.
5 From the list of storage devices, select the device that has a specific value displayed in the Snapshot
Volume column.
The value present in the Snapshot Volume column indicates that the device is a copy that contains a
copy of an existing VMFS datastore.
6 Under Mount Options, select Keep Existing Signature.
7 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.
Resignature a VMFS Datastore Copy
Use datastore resignaturing if you want to retain the data stored on the VMFS datastore copy.
When resignaturing a VMFS copy, ESXi assigns a new signature (UUID) to the copy, and mounts the
copy as a datastore distinct from the original. All references to the original signature from virtual machine
configuration files are updated.
vSphere Storage
VMware, Inc. 181