On Tue, May 2, 2023, at 8:14 AM, Roger Heflin wrote:
Hardware or software raid typically makes and exact copy of what they are mirroring.
I was just preparing a reply to this. I had been confused since I do run Linux MD raid 1 and I was pretty sure I had matching UUID. Here are two examples that show older and newer raid version/type:
(note that they use matching UUID for the members, but use a unique UUID for the raid, and that there is also a unique PARTUUID for each)
8:39-doug@wombat-~>blkid | grep 7: /dev/sdb7: UUID="a1efda72-102e-139f-6435-186fb839f57c" TYPE="linux_raid_member" PARTUUID="28f4447c-07" /dev/md7: UUID="8688b29b-c244-4dc6-88bc-02f282396dc3" BLOCK_SIZE="4096" TYPE="ext4" /dev/sda7: UUID="a1efda72-102e-139f-6435-186fb839f57c" TYPE="linux_raid_member" PARTUUID="87e58b90-07"
8:39-doug@wombat-~>blkid | grep 1: /dev/sdb1: UUID="deb9b913-0a73-90d8-6b37-12e5156fce03" UUID_SUB="50b1ecf9-a7bd-6ba5-131e-4bbde91735c8" LABEL="wombat.wombatz.com:boot" TYPE="linux_raid_member" PARTUUID="28f4447c-01" /dev/sda1: UUID="deb9b913-0a73-90d8-6b37-12e5156fce03" UUID_SUB="8efb2a67-f08a-4ba9-186f-11f7afec25c7" LABEL="wombat.wombatz.com:boot" TYPE="linux_raid_member" PARTUUID="87e58b90-01" /dev/md1: UUID="72f36fca-b84e-45f4-8621-d85b14a32ff3" BLOCK_SIZE="4096" TYPE="ext4"