I use this command to change the UUID of a volume to a defined value, so I can easily mount external drives.
UUID can be something like: 77777777-3333-3333-3333-bbbbbbbbbbbb
blkid | grep UUID
umount /dev/sdb1
tune2fs -U "{UUID}" /dev/sdb1
From the tune2fs man pages:
-U UUID
Set the universally unique identifier (UUID) of the filesystem
to UUID. The format of the UUID is a series of hex digits sepa-
rated by hyphens, like this:
"c1b9d5a2-f162-11cf-9ece-0020afc76f16". The UUID parameter may
also be one of the following:
clear clear the filesystem UUID
random generate a new randomly-generated UUID
time generate a new time-based UUID
The UUID may be used by mount(8), fsck(8), and /etc/fstab(5)
(and possibly others) by specifying UUID=uuid instead of a block
special device name like /dev/hda1.
linux command disks