I have a situation where after upgrading ESXi from 6.0.0 to 6.7.0 I have lost one out of three of my datastores. The disk with the datastore on it appears in the ESXi interface as VMFS and is available for re-allocation / erasure, but the datastore on the disk isn't mounted.
I went back to ESXi 6.0.0 but I have the same problem with the disk / datastore.
After logging in to the console I see that it is listed in /dev/disks.
How can I mount this and use it again? Is there a problem with the disk?
Any advice will be greatly appreciated.