Hi Andrew,

On 12/07/2015 08:26 PM, Andrew Wilkins wrote:

Hi, please can someone help me with a raid array which as gone wrong
On Friday a backup server was rebooted, but failed to boot, possibly
with an unrelated issue


On Monday someone booted from a usb disk to try and recover it
they were originally able to assemble the array but now they are not,
2 out of the 5 drives are showing out of date.
Device 1 is showing
  Bad Block Log : 512 entries available at offset 72 sectors
  Array State : AAAAA
and is showing 256 less a events
last updated 2 hours before the others

Device 4 is showing
 Array State : A.AAA
and 2 less events
last update 1 hour before the others

The rest all show
 Array State : A.AA.

I've tried manually assembling without device 1, but even with --force
it refused to assemble, force seems to do nothing at all, i am
assuming this maybe because the array state has been updated to say
missing for 2 devices.

The example here
https://raid.wiki.kernel.org/index.php/RAID_Recovery
seems to suggest that in my situation recreating might be my only option

Possibly. Let's try all other options first.

Are there any better options before i go ahead and do this?

At least one anomaly below.

/dev/sdb1:

     Array UUID : 7847e506:deaf87e5:7c6cd502:abb20cf1

/dev/sdc1:

     Array UUID : xxxxxxxx:xxxxxxxx:xxxxxxxx:abb20cf1

How did this happen ? ^^^^^^^^^^^^^^^^^^^^^^

/dev/sdd1:

     Array UUID : 7847e506:deaf87e5:7c6cd502:abb20cf1

/dev/sde1:

     Array UUID : 7847e506:deaf87e5:7c6cd502:abb20cf1

/dev/sdf1:

     Array UUID : 7847e506:deaf87e5:7c6cd502:abb20cf1

Try forcing re-assembly with sdb1, sdd1, sde1, and sdf1.

If that doesn't work with your current environment, try again with new
kernel and mdadm from booting a rescue environment.  I usually recommend
the LiveCD from sysrescuecd.org.

If that succeeds (in either case), add sdc1 and let it rebuild before
doing anything else.

Phil