Use the vmkfstools command to list attributes of a VMFS datastore.

-P|--queryfs
      -h|--humanreadable

When you use this option on any file or directory that resides on a VMFS datastore, the option lists the attributes of the specified datastore. The listed attributes typically include the file system label, the number of extents for the datastore, the UUID, and a list of the devices where each extent resides.

Note: If any device backing VMFS file system goes offline, the number of extents and available space change accordingly.

You can specify the -h|--humanreadable suboption with the -P option. If you do so, vmkfstools lists the capacity of the volume in a more readable form.

Example of Listing VMFS Attributes

~ vmkfstools -P -h /vmfs/volumes/my_vmfs
VMFS-5.81 (Raw Major Version: 14) file system spanning 1 partitions.
File system label (if any): my_vmfs
Mode: public
Capacity 99.8 GB, 97.5 GB available, file block size 1 MB, max supported file size 62.9 TB
UUID: 571fe2fb-ec4b8d6c-d375-XXXXXXXXXXXX
Partitions spanned (on "lvm"):
        eui.3863316131XXXXXX:1
Is Native Snapshot Capable: YES