Making this type of change on the storage array results in assigning a new LUN ID (UUID or Serial Number) to all LUNs presented via the modified ports/FAs.
VMFS3 metadata identifies the volumes by several properties which include the LUN number and the LUN ID (UUID or Serial Number). Because the LUNs now have new UUIDs, the resulting mismatch with the metadata leads to LVM identifying the volumes as snapshots.
You must resignature the VMFS3 volumes to make them visible again.
Caution:
Before performing the steps in this article:
Wait for a maintenance window
Make sure all virtual machines are backed up properly
Do not deviate from these steps.
To resignature the VMFS3 volumes from the command line:
Power off all virtual machines on all ESX hosts that are stored on the volume.
Run the following command to re-read the volume on each ESX host:
# vmkfstools -V
If this works, the problem is resolved. If this does not work, proceed to step 3.
Remove all the virtual machines on that volume from the inventory in the VirtualCenter server.
Warning: Do not delete the virtual machines from disk. Remove them from the inventory.
Log in to each host.
Run the following command to verify which HBAs are providing access to the LUN:
# esxcfg-mpath -l | less
To set the ESX host to resignature all datastores detected as snapshots on the next rescan, run the following command:
