On 16/10/2022 22:38, Steve Kolk wrote:
I have a system that was running Ubuntu 18.04 server with a 5 drive
RAID 6 array using mdadm. I had a hard drive failure, but instead of
the array it was the OS hard drive that completely failed. I also do
not have access to the original mdadm.conf file.
In an attempt to get my array back up, I booted Ubuntu 22.04 from a
USB and tried to assemble and mount the array. It did not work.
Trying some diagnostic steps I found online, it seems to be claiming
that there is no md superblock on any of the drives.
From this site? https://raid.wiki.kernel.org/index.php/Linux_Raid
Try https://raid.wiki.kernel.org/index.php/Linux_Raid#When_Things_Go_Wrogn
I've included the commands I ran and their output below. Does anyone
have any advice on what next steps I can take? I have no reason to
think these drives have failed mechanically (much less all of them). I
also tried with Ubuntu 18.04 and got the same results.
If you've got python 2.7, can you run lsdrv? Hopefully that will give us
some more clues.
Provided the data itself isn't damaged, you should be able to retrieve
your array. Read up the section on overlays, that will protect your data
from being overwritten while you play around trying to recover it.
The other thing I would do here, is five drives is a lot to try and get
right. I'd pick just three drives, and try to get them to assemble
correctly (using overlays for safety!). Once you've got three drives to
give you a functional array, you can then try and get the other two
correct before the final recovery.
What can you remember about the system? What version of superblock? And
something I've noticed that seems weird, why do your drives have
partitions 1 & 9, but not 2-8? That is well odd ... Have you rebuilt the
array in any way, or is it exactly as originally created? Etc etc the
more information you can give us the better.
Let us know how you get on with this, and then we'll come back with more.
Cheers,
Wol
