Resolving Duplicate UUIDs

1. Identification

Before making changes, identify which partitions are sharing the same UUID.

• Quick View: lsblk -f

• Detailed View: blkid

Look for matching strings in the UUID column for different device names (e.g., /dev/sda1 and /dev/sdb1 having the same ID).

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2. File System Specific Fixes

EXT4 File Systems

For EXT2, EXT3, or EXT4 partitions, you can generate a new random UUID while the drive is live or unmounted.

Bash

Copy# Syntax: sudo tune2fs -U random /dev/sdX#
sudo tune2fs -U random /dev/sdb1

XFS File Systems

Warning: The partition must be unmounted before changing the UUID on XFS.

Bash

Copy# 1. Unmount the partition
sudo umount /dev/sdX#

# 2. Generate a new UUID
sudo xfs_admin -U generate /dev/sdX#

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3. Logical Volume Management (LVM)

LVM uses UUIDs for Physical Volumes (PV) and names for Volume Groups (VG). Cloning an LVM disk creates duplicates of both.

Step A: Identify LVM Duplicates

Use these commands to check for "Duplicate PV" warnings:

• pvs (Physical Volumes)

• vgs (Volume Groups)

• pvdisplay

Step B: Assign New PV UUID

If two Physical Volumes have the same UUID, change one of them:

Bash

Copysudo pvchange -u /dev/sdX2

Step C: Rename Duplicate Volume Groups

If two Volume Groups have the same name, use the VG UUID (found in vgs) to rename one of them to avoid conflicts.

Bash

Copy# sudo vgrename [VG_UUID] [new_vg_name]
sudo vgrename a1b2c3-d4e5-f6g7-h8i9 new_vg_name

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4. Post-Change Configuration (Critical)

Changing a UUID will break your automatic mounting if the system is looking for the old ID.

Update /etc/fstab

1. Run blkid to copy the new UUID.

2. Open the fstab file:

   Bash

   Copysudo nano /etc/fstab
   

3. Replace the old UUID string with the new one for the respective mount point.

Update Bootloader (If System Partition)

If you changed the UUID of your root (/) or boot partition, you must update your GRUB configuration:

Bash

Copysudo update-grub

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5. Verification

Finalize the process by testing the mounts and rebooting.

1. Test Mounts: sudo mount -a (If no errors appear, your fstab is correct).

2. Reboot: sudo reboot

3. Confirm: After rebooting, run lsblk -f one last time to ensure all IDs are unique and mounted correctly.