How do I find the UUID of a partition

Question

I'm running Ubuntu, and want to find out the UUID of a particular partition. I know I can use e2label /dev/sda1 to find out the partition label, but there doesn't seem to be a similar way to find the UUID.

Answer 1

Another command that might be available and also works quite well for this is 'blkid'. It's part of the e2fsprogs package. Examples of it's usage:

Look up data on /dev/sda1:

topher@crucible:~$ sudo blkid /dev/sda1
/dev/sda1: UUID="727cac18-044b-4504-87f1-a5aefa774bda" TYPE="ext3"

Show UUID data for all partitions:

topher@crucible:~$ sudo blkid
/dev/sda1: UUID="727cac18-044b-4504-87f1-a5aefa774bda" TYPE="ext3"
/dev/sdb: UUID="467c4aa9-963d-4467-8cd0-d58caaacaff4" TYPE="ext3"

Show UUID data for all partitions in easier to read format: (Note: in newer releases, blkid -L has a different meaning, and blkid -o list should be used instead)

topher@crucible:~$ sudo blkid -L
device     fs_type label    mount point    UUID
-------------------------------------------------------------------------------
/dev/sda1 ext3             /              727cac18-044b-4504-87f1-a5aefa774bda
/dev/sdc  ext3             /home          467c4aa9-963d-4467-8cd0-d58caaacaff4

Show just the UUID for /dev/sda1 and nothing else:

topher@crucible:~$ sudo blkid -s UUID -o value /dev/sda1
727cac18-044b-4504-87f1-a5aefa774bda

Answer 2

The recommended way to do this is to do

sudo vol_id -u /dev/sda2

For more on using UUIDs, see this article (from ubuntu help, but should work for any linux distro using UUIDs).

As noted in comments to this question, vol_id may not be in your path. On ubuntu it is in /sbin so the above will work. For fedora it appears to need

sudo /lib/udev/vol_id -u /dev/sda2

If other distributions have vol_id in other places then post a comment and I'll add it to this answer.

Answer 3

The easiest way to do this for ext2/ext3/ext4 is:

/sbin/tune2fs -l /dev/sda1

Answer 4

You can use the following to get the UUID for a particular drive,

sudo vol_id -u /dev/sda1

or you can use this to list all UUIDs for the attached media,

ls /dev/disk/by-uuid

Answer 5

Assuming you want the UUID for sda1, you could try something like this:

for v in /dev/disk/by-uuid/* ; do echo "`readlink $v`: $v" | grep ../sda1 | cut -d\: -f2 | cut -d/ -f5 ; done

Adjust sda1 accordingly. To get the UUIDs for all partitions, drop the greps and cuts, a la:

for v in /dev/disk/by-uuid/* ; do echo "`readlink $v`: $v" ; done

Sample output for sda1 on my desktop:

[mihailim@home ~]$ for v in /dev/disk/by-uuid/* ; do echo "`readlink $v`: $v" | grep ../sdb3 | cut -d\: -f2 | cut -d/ -f5 ; done
dc8c49f1-e2dc-46bc-ba02-013f26c85f70

Edit: Please note that this solution, while more contrived than the udev->vol_id one, does not require root privileges, will work on any post-2005 or so kernel, and relies on tools present in any Linux distribution which are by default in the path for any user.