Are you sure you did not partition devices that did not previously
have partition tables?

Partition tables will typically cause the under device (sda) to be
ignored by all of tools since it should never having something else
(except the partition table) on it.

I have had to remove incorrectly added partition tables/blocks to make
lvm and other tools again see the data.  Otherwise the tools ignore
it.

On Wed, Jan 24, 2024 at 12:06 PM RJ Marquette [off-list ref] wrote:

Other than sdc (as you noted), the other array drives come back like this:

root@jackie:/etc/mdadm# mdadm --examine /dev/sda
/dev/sda:
  MBR Magic : aa55
Partition[0] :   4294967295 sectors at            1 (type ee)

root@jackie:/etc/mdadm# mdadm --examine /dev/sda1
mdadm: No md superblock detected on /dev/sda1.


Trying your other suggestion:
root@jackie:/etc/mdadm# mdadm --assemble /dev/md0 /dev/sdb1 /dev/sde1 /dev/sdf1 /dev/sdg1
mdadm: no recogniseable superblock on /dev/sdb1
mdadm: /dev/sdb1 has no superblock - assembly aborted

root@jackie:/etc/mdadm# mdadm --assemble /dev/md0 /dev/sdb /dev/sde /dev/sdf /dev/sdg
mdadm: Cannot assemble mbr metadata on /dev/sdb
mdadm: /dev/sdb has no superblock - assembly aborted


Basically I've tried everything here:  https://raid.wiki.kernel.org/index.php/Linux_Raid

The impression I'm getting here is that we aren't really sure what the issue is.  I think tonight I'll play with some of the BIOS settings and see if there's something in there.  If not I'll swap back to the old motherboard and see what happens.

Thanks.
--RJ





On Wednesday, January 24, 2024 at 12:06:26 PM EST, Sandro [off-list ref] wrote:





On 24-01-2024 13:17, RJ Marquette wrote:

quoted

When I try the command you suggested below, I get:
root@jackie:/etc/mdadm# mdadm --assemble /dev/md0 /dev/sd{a,b,e,f,g}1
mdadm: no recogniseable superblock on /dev/sda1
mdadm: /dev/sda1 has no superblock - assembly aborted

Try `mdadm --examine` on every partition / drive that is giving you
trouble. Maybe you are remembering things wrong and the raid device is
/dev/sda and not /dev/sda1.

You can also go through the entire list (/dev/sd*), you posted earlier.
There's no harm in running the command. It will look for the superblock
and tell you what has been found. This could provide the information you
need to assemble the array.

Alternatively, leave sda1 out of the assembly and see if mdadm will be
able to partially assemble the array.

-- Sandro