Several times primarily when using HDS storage I have been required to change the host mode settings between Sun cluster and Linux. Normally this is due to SRM and the SRA requirements. When this is done the Canonical Name of the devices changes and the VMFS Datastore will disappear, Generally you add the VMFS device back re-signaturing it in the process.
Several things I have noticed:
1. The VMFS datastores cannot be added back whilst connected to the vCenter Server, you must connect directly to the ESX host, you receive the error "Cannot change host configuration".
2. Adding the VMFS back on one host, will not propagate to other hosts.
3. It takes a long time to add the storage back as each VMFS takes approximately 3 minutes to find the devices, this is doen one at a time.
I don't understand why any of the above issues occur but notice that each time I have done this I have had the same issues taking a long time to add back the storage. Can anyone explain why this occurs?