I recently had an issue where I lost some network connectivity with my iSCSI NAS where my ESXi datastores are. After reconnecting ESXi shows it mounts the target however the datastore does not appear. When I go to add new storage it presents the LUN and shows there is a partition there (see attached pic) however I can't seem to figure out how to use that partition without wiping it out. I am on ESXi 6. Any ideas?
Please take a look at https://kb.vmware.com/kb/1011387 to find out whether the LUN is detected as a Snapshot LUN. I'd suggest you follow the "Command line" section running the esxcli commands.
