VMFS Volumes Missing!?!?!

Here's the scenario: After performing maintenance on an ESX server (patches, storage re-scan, reboot), VMFS volumes are no longer visible, even though the hosting LUN can be seen on the Storage Adapters page of the ESX Configuration tab.  Most VMware administrators will see this play out at some point; I saw it in one of my environments today and figured I should make a note of the steps required to correct the issue. Typically, the root cause of the issue is a change on the storage array that causes the h(id) of the LUN(s) in question to change.  This change could be anything from an … [Read more...]