How to find UUID of a disk

# man blkid
# blkid -s UUID /dev/sdb1
/dev/sdb1: UUID="be74195b-49d0-4195-8e18-171e17165d6a"
# blkid -s UUID -o value /dev/sdb1
be74195b-49d0-4195-8e18-171e17165d6a