Hello All- I attached an AWS EBS volume to `xvdh` that was from a terminated EC2 machine to another machine. The filesystem shared a btrfs UUID since they came from an identical install. When I mounted the new EBS volume to /mnt something very odd happened: Before: $ mount /dev/xvda9 on / type btrfs (rw,relatime,ssd,space_cache) /dev/xvda3 on /usr type ext4 (ro,relatime) After: # mount /dev/xvdh9 /mnt # mount /dev/xvdh9 on / type btrfs (rw,relatime,ssd,space_cache) /dev/xvdh9 on /mnt type btrfs (rw,relatime,ssd,space_cache) It seems that btrfs gets very confused when there are matching UUIDs and /mnt didn't contain the contents that I expected. To work around the issue I booted a non-identical machine image that had a different btrfs UUID and attached the backup EBS volume again and everything worked as expected. What is the right way of handling this? Attaching EBS volumes from snapshots or old identical machines is a common use case. Thanks! Brandon -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
