We can list all detected VMFS snapshot volumes with the following command, even if for some reason we aren't able to mount the volume from within vSphere client (it was my case in a lab recently…). This command will list the names of the VMFS datastores and their UUIDs.

esxcfg-volume -l

To resignature the volume. The general syntax is following:

  esxcfg-volume -M

Vladan knows...