Mike Berger wrote:
Created the array: # mdadm --create --verbose /dev/md0 --level=5 --chunk=128 --raid-devices=3 /dev/sdb1 /dev/sdc1 /dev/sdd1
eek ... a RAID5 on 3 drives? Did you do an mdadm --detail --scan > /etc/mdadm.conf after this? [...]
At this point I used the newly created array for a few days without any issues at all.
... but did you update mdadm.conf as above? [...]
Now I tried to assemble the array manually using the following commands, all of which failed (note that I had never edited mdadm.conf). # mdadm --assemble --scan
This generally requires an /etc/mdadm.conf (or similar /etc/mdadm/mdadm.conf)
# mdadm --assemble --scan --uuid=3128da32:c5e4ff31:b43fc0e6:226924cf # mdadm --assemble /dev/md0 /dev/sdb1 /dev/sdc1 /dev/sdd1 # mdadm --assemble -f /dev/md0 /dev/sdb1 /dev/sdc1 /dev/sdd1 # mdadm --assemble --uuid=3128da32:c5e4ff31:b43fc0e6:226924cf /dev/md0 /dev/sdb1 /dev/sdc1 /dev/sdd1
You can often (re)construct this file if you forget to create it with a little detective work ...
mdadm --examine /dev/sdb1 could be your friend. [...]
# fsck.ext4 -n /dev/md0 I get: fsck.ext4: Superblock invalid, trying backup blocks... fsck.ext4: Bad magic number in super-block while trying to open /dev/md0 I've tried specifying the blocksize and specifying the superblock manually using the backup superblocks from when I ran mkfs.ext4, but get the same result. I haven't dared to run fsck without -n until I hear from someone more knowledged. So, if anyone has any suggestions on how I can get md0 mounted or recover my data it would be much appreciated.
I am not completely sure, but I would bet that with the changes you have made, that this data may not be recoverable at this point.
Before you do anything else, I would definitely suggest creating the mdadm.conf file properly as noted above.
Joe -- Joe Landman Scalable Informatics LLC, email: landman@xxxxxxxxxxxxxxxxxxxxxxx web : http://www.scalableinformatics.com -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
