Background: The host OS is an Azure Oracle Linux 7.8 instance with its OS disk mounted via
btrfs. I have another Azure Oracle Linux 7.8 instance that is broken, so I wanted to attach its disk to debug. Once attached to my host OS, because the attached disk is from the same Oracle Linux 7.8 image, its UUIDs are the same as my host, and it seems to create some confusion/corruption with mounts. Below is the output of
lsblk after Azure has finished attaching the image:
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sdb 8:16 0 4G 0 disk └─sdb1 8:17 0 4G 0 part /mnt sr0 11:0 1 628K 0 rom fd0 2:0 1 4K 0 disk sdc 8:32 0 50G 0 disk ├─sdc15 8:47 0 495M 0 part ├─sdc2 8:34 0 49G 0 part / <--- isn't really sdc2, its mounted from sda2 ├─sdc14 8:46 0 4M 0 part └─sdc1 8:33 0 500M 0 part sda 8:0 0 100G 0 disk ├─sda2 8:2 0 99G 0 part ├─sda14 8:14 0 4M 0 part ├─sda15 8:15 0 495M 0 part /boot/efi └─sda1 8:1 0 500M 0 part /boot
You can see it thinks root
/ is mounted via
/dev/sdc2, but this disk (
/dev/sdc) has literally only just been attached. I can only presume the UUID conflict is causing this (could it be anything else?), but now I can’t mount the real/attached
/dev/sdc2 to debug that disk because the system thinks its already mounted.
Is there anyway to prevent this happening as I attach the disk?