Neil, thanks very much. I found the answer to my problem in the archives of this list, after no small amount of searching. What I did was recreate the array, re-writing all of the superblocks, and leaving out the drive that wasn't fully reconstructed: mdadm --create /dev/md0 -c32 -l5 -n4 /dev/hda1 missing /dev/hde1 /dev/hdg1 Then I FSCK'ed the filesystem (read-only) to see if it was reasonable. root@radon:/mnt# fsck -n /dev/md0 fsck 1.37 (21-Mar-2005) e2fsck 1.37 (21-Mar-2005) Warning: skipping journal recovery because doing a read-only filesystem check. /dev/md0: clean, 94101/29327360 files, 51942315/58633008 blocks All clean :) mount -o ro /dev/md0 /mnt/files Then I mounted it ro and was able to copy files off. Thanks linux-raid! :) On 11/20/05, Remi Broemeling <rbroemeling@xxxxxxxxx> wrote: > I have (had?) a 4-disk RAID5 array (/dev/md1), consisting of: > > /dev/hda1 > /dev/hdc1 > /dev/hde1 > /dev/hdg1 > > After some months of uptime, I had to reboot the system for a > non-related issue -- and when it came back up, the array was running > in degraded mode. After further investigating, I had found that it > did not auto-add /dev/hdc1 to the RAID5 array because I had forgotten > to set it's type to 0xFD. My bad. > > I made up my mind to fix it, but didn't have the time at the moment > and so I shrugged, made a mental note of it, and re-added the drive to > the array manually with: > > mdadm /dev/md1 -a /dev/hdc1 > > A `cat /proc/mdstat` showed me what I expected (that the array was > rebuilding), so I shrugged and went to do other things. > > Some hours later, I returned to see that /dev/hdg1 had failed during > the rebuild process. Now I have a completely snarfed array, with two > drives that mdadm sees as clean (/dev/hda1 and /dev/hde1), a > could-be-mostly-rebuilt-but-still-partial drive (/dev/hdc1) and a > corrupted-but-who-knows-how-badly drive (/dev/hdg1). > > I was considering retiring the machine anyway, to be replaced with > something newer... so right now I just want to save anything that I > can off of the machine. Is there any way for me to resurrect the > array and get some of my data off of it? > > I tried the following, which I saw in the list archives: > > mdadm -A /dev/md1 --uuid=a38910a6:51582805:6ccb5711:4ac501b2 --force > /dev/hdg1 /dev/hde1 /dev/hda1 /dev/hdc1 > > ... but the response message was: > > "mdadm: /dev/md1 assembled from 2 drives and 2 spares - not enough to > start the array." > > Any help would be greatly appreciated. > > mdadm --examine output for each of the involved partitions follows. > > /dev/hdg1: > Magic : a92b4efc > Version : 00.90.00 > UUID : a38910a6:51582805:6ccb5711:4ac501b2 > Creation Time : Mon Oct 4 14:48:20 2004 > Raid Level : raid5 > Raid Devices : 4 > Total Devices : 3 > Preferred Minor : 1 > > Update Time : Sun Nov 20 01:11:15 2005 > State : clean > Active Devices : 2 > Working Devices : 3 > Failed Devices : 2 > Spare Devices : 1 > Checksum : dfd92d15 - correct > Events : 0.5800013 > > Layout : left-symmetric > Chunk Size : 32K > > Number Major Minor RaidDevice State > this 4 34 1 4 spare /dev/hdg1 > > 0 0 3 1 0 active sync /dev/hda1 > 1 1 0 0 1 faulty removed > 2 2 33 1 2 active sync /dev/hde1 > 3 3 0 0 3 faulty removed > 4 4 34 1 4 spare /dev/hdg1 > > /dev/hde1: > Magic : a92b4efc > Version : 00.90.00 > UUID : a38910a6:51582805:6ccb5711:4ac501b2 > Creation Time : Mon Oct 4 14:48:20 2004 > Raid Level : raid5 > Raid Devices : 4 > Total Devices : 3 > Preferred Minor : 1 > > Update Time : Sun Nov 20 01:11:15 2005 > State : clean > Active Devices : 2 > Working Devices : 3 > Failed Devices : 2 > Spare Devices : 1 > Checksum : dfd92d16 - correct > Events : 0.5800013 > > Layout : left-symmetric > Chunk Size : 32K > > Number Major Minor RaidDevice State > this 2 33 1 2 active sync /dev/hde1 > > 0 0 3 1 0 active sync /dev/hda1 > 1 1 0 0 1 faulty removed > 2 2 33 1 2 active sync /dev/hde1 > 3 3 0 0 3 faulty removed > 4 4 34 1 4 spare /dev/hdg1 > > /dev/hdc1: > Magic : a92b4efc > Version : 00.90.00 > UUID : a38910a6:51582805:6ccb5711:4ac501b2 > Creation Time : Mon Oct 4 14:48:20 2004 > Raid Level : raid5 > Raid Devices : 4 > Total Devices : 4 > Preferred Minor : 1 > > Update Time : Sun Nov 20 01:10:31 2005 > State : clean > Active Devices : 2 > Working Devices : 4 > Failed Devices : 2 > Spare Devices : 2 > Checksum : dfd92d01 - correct > Events : 0.5800012 > > Layout : left-symmetric > Chunk Size : 32K > > Number Major Minor RaidDevice State > this 5 22 1 5 spare /dev/hdc1 > > 0 0 3 1 0 active sync /dev/hda1 > 1 1 0 0 1 faulty removed > 2 2 33 1 2 active sync /dev/hde1 > 3 3 0 0 3 faulty removed > 4 4 34 1 4 spare /dev/hdg1 > 5 5 22 1 5 spare /dev/hdc1 > > /dev/hda1: > Magic : a92b4efc > Version : 00.90.00 > UUID : a38910a6:51582805:6ccb5711:4ac501b2 > Creation Time : Mon Oct 4 14:48:20 2004 > Raid Level : raid5 > Raid Devices : 4 > Total Devices : 3 > Preferred Minor : 1 > > Update Time : Sun Nov 20 01:11:15 2005 > State : clean > Active Devices : 2 > Working Devices : 3 > Failed Devices : 2 > Spare Devices : 1 > Checksum : dfd92cf4 - correct > Events : 0.5800013 > > Layout : left-symmetric > Chunk Size : 32K > > Number Major Minor RaidDevice State > this 0 3 1 0 active sync /dev/hda1 > > 0 0 3 1 0 active sync /dev/hda1 > 1 1 0 0 1 faulty removed > 2 2 33 1 2 active sync /dev/hde1 > 3 3 0 0 3 faulty removed > 4 4 34 1 4 spare /dev/hdg1 > - 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
