Changing Disk UUID After Cloning

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So, I have a CentOS 6 system, and I want to make several clones of it. I’m using Clonezilla to clone the drives; that’s no problem. But the drive UUIDs are driving me up the wall. After cloning, the two drives have the same UUID, but I’d like each clone to have different UUIDs so there’s no possibility of a conflict when I am running diagnostics with two drives installed, etc. But when I change the UUID of the /boot or / partition (even if I update /etc/fstab), the system won’t boot; it GRUBs OK (after I use recovery mode to rerun grub-install), but never gets to the ‘Welcome to CentOS ” message. Do I need to “rebless” vmlinuz or initrd or initramfs in the /boot partition if I change the drive UUID?

Or should I just ignore UUID and go back to using labels in /etc/fstab (which is what I did in CentOS 5)?


5 thoughts on - Changing Disk UUID After Cloning

  • Glenn Eychaner wrote:

    I hate UUIDs. There is *no* way you can remember them, when you’re sitting at a console trying to bring something up. We stayed with labels, which always work, and are easy to change.


  • *If the disk is in /dev/sda2 then generate a new UUID with uuidgen and apply it with tune2fs

    myhost # uuidgen b13fddae-a3c3-4d17-8220-7773eb404dec myhost # tune2fs -U b13fddae-a3c3-4d17-8220-7773eb404dec /dev/sda2



  • Not on my system; CentOS 6 uses grub 0.97, and my grub.conf file doesn’t contain any UUIDs that I can find.

    That’s probably the problem; I will make another attempt in the morning, if I decide that I care. I may simply decide that I don’t care if I have duplicated UUIDs between workstations, if it becomes too much trouble to fix. :-)


  • tunee2fs or reisrfstune can probably do what you want.

    I’d use labels and I’d make them systematic labels, e.g. disklabel-partitionlabel. This is likely to start another religious flame war.