Re: RAID 6, 6 device array - all devices lost superblock

Andy Smith
2022-08-28T17:24:25Z

Hi Peter,

On Sat, Aug 27, 2022 at 10:00:32PM -0400, Peter Sanders wrote:
> After the hardware was replaced, my array will not assemble - mdadm
> assemble reports no RAID superblock on the devices.
> root@superior:/etc/mdadm# mdadm --assemble --scan --verbose
> mdadm: looking for devices for /dev/md/0
> mdadm: cannot open device /dev/sr0: No medium found
> mdadm: No super block found on /dev/sda (Expected magic a92b4efc, got 00000000)
> mdadm: no RAID superblock on /dev/sda
> mdadm: No super block found on /dev/sdb (Expected magic a92b4efc, got 00000000)
> mdadm: no RAID superblock on /dev/sdb

I'm wondering if this is one of those motherboards that at boot
helpfully writes a new empty GPT on any drive that it thinks doesn't
have any kind of partitioning. I say this because:

- It looks like you're using sd{a,b} etc with no partitions
- I've heard of motherboards that do this
- You say you just switched to a new motherboard

Cheers,
Andy