Dumbo trying to resuscitate a RAID

madelk · 03-11-2013, 11:30 PM

Using a mirrored RAID to keep important files is a good idea.
Using a mirrored RAID on Linux with a guy who has no idea what he's doing.. not so much.

I have/had two drives in a mirrored RAID on ubuntu and my boot drive (separate from the RAID) failed.
I've now reinstalled the latest Ubuntu and I've been doing what I can to get things up and going again. Here's what my files are showing:

mdadm.conf

ARRAY /dev/md/New RAID Array metadata=1.2 UUID=37a45ace:6b444ce7:3dc065e0:ae6b2c9a

cat /proc/mdstat

Personalities : [raid1]
md127 : active raid1 sdb1[0] sdc1[1]
1465004736 blocks super 1.2 [2/2] [UU]

But mounting is giving me an error showing that it can't find a valid filesystem or a bad superblock.

GParted shows md127 as having a 1.36tb of unallocated space (which has me kinda freaked out)

------------

Have I not setup mdadm correctly and has that messed things up? The RAID was created using diskutility with what I believe was an older version of Ubuntu.

Any help's appreciated, even if I know the files are gone at least I'll know to stop trying.

jlinkels · 03-12-2013, 06:33 PM

I hate myself and I am sure you are gonna join me.

I had this as well, and I solved it --- 3 years ago and I can't remember how.

Your data is not gone.

It can have to do something with UUID. Check the UUID of your array (mdadm command, I think it is scan) and compare it with the mdadm.conf.

Check also how fstab mounts the array. If it does by UUID, those must match.

jlinkels

madelk · 03-12-2013, 11:49 PM

Got it!
I tried so many things it's hard to know exactly what it was, but should someone else have this issue (or future me) then..
I unplugged one of the drives and rebooted up until then I was always getting an error telling me that the drive had no partition on it.
Thankfully it seems that the drive manager tool I used to create the raid no longer supports creating raids. I'm rather sure a lot of my issue was because the array was called "new raid array" and something somewhere seemed to remember that and cause issues

chrism01 · 03-13-2013, 12:38 AM

blkid is the cmd (or at least on the will do it) eg

Code:

 blkid
/dev/sdb1: UUID="18c18f7a-293c-422a-a4dc-a3d597462f04" TYPE="ext4" 
/dev/sdb2: UUID="7eaddad2-5314-40a9-9db5-c4a6c9721233" TYPE="ext4" 
/dev/sdb3: UUID="ec5d1d44-c2fa-4d9a-ba13-19038140b9d7" TYPE="swap" 
/dev/sda5: UUID="7b090473-f3c8-4256-994c-1f42fdddd2cf" TYPE="swap" 
/dev/sda1: LABEL="/" UUID="b1d86415-dd5b-41ca-a77f-a0c20d054395" SEC_TYPE="ext2" TYPE="ext3" 
/dev/sda2: LABEL="SWAP-sda2" TYPE="swap" 
/dev/sda3: UUID="51630f8d-a327-49be-86f6-3f64e67e5fc6" TYPE="ext4" 
/dev/sda7: UUID="ce7067b3-2196-469b-b5b4-ba3821bae491" TYPE="ext4" 
/dev/sda8: UUID="d948c6c7-e930-4d66-865d-5e24caa99be6" TYPE="ext4" 
/dev/sda6: UUID="7b22f324-5b26-4206-8fed-a38bff58596c" TYPE="ext3"