The good news is that my RAID5 array was configured as 5 + 1 spare. I powered down the server, used the Maxtor PowerMax utility to identify the bad disk, pulled it out and re-booted. My array is currently re-syncing.
[root@dude root]# mdadm --detail /dev/md5
/dev/md5:
Version : 00.90.01
Creation Time : Thu Jul 29 21:41:38 2004
Raid Level : raid5
Array Size : 974566400 (929.42 GiB 997.96 GB)
Device Size : 243641600 (232.35 GiB 249.49 GB)
Raid Devices : 5
Total Devices : 5
Preferred Minor : 5
Persistence : Superblock is persistent Update Time : Fri Nov 19 20:52:58 2004
State : dirty, resyncing
Active Devices : 5
Working Devices : 5
Failed Devices : 0
Spare Devices : 0 Layout : left-symmetric
Chunk Size : 128KRebuild Status : 0% complete
UUID : a4bbcd09:5e178c5b:3bf8bd45:8c31d2a1
Events : 0.1765551 Number Major Minor RaidDevice State
0 8 2 0 active sync /dev/sda2
1 8 18 1 active sync /dev/sdb2
2 8 34 2 active sync /dev/sdc2
3 8 50 3 active sync /dev/sdd2
4 8 66 4 active sync /dev/sde2Thinking about what happened, I would have expected that the bad drive would just be removed from the array and spare activated and re-syncing started automatically.
What actually happened was that I rebooted to activate a new kernel and the box didn't come back up. As the machine runs headless, I had to power it off and take it to a monitor/keyboard to check it. In the new location it came up fine so I shut it down again and put it back in my "server room" (read: cellar). I still couldn't see it from the network so I dragged an old 14" CRT out of the shed and connected it up. The login prompt was there but there was an "ata2 timeout" error message and the console was dead. I power-cycled to reboot and as it booted I saw a message something like "postponing resync of md0 as it uses the same device as md5. waiting for md5 to resync. I then got a further ata timeout error. I had to physically disconnect the bad drive and reboot in order to re-start the re-sync.
Further md information:
[root@dude log]# mdadm --detail --scan
ARRAY /dev/md2 level=raid1 num-devices=2 UUID=11caa547:1ba8d185:1f1f771f:d66368c9
devices=/dev/sdc1
ARRAY /dev/md1 level=raid1 num-devices=2 UUID=be8ad31a:f13b6f4b:c39732fc:c84f32a8
devices=/dev/sdb1,/dev/sde1
ARRAY /dev/md5 level=raid5 num-devices=5 UUID=a4bbcd09:5e178c5b:3bf8bd45:8c31d2a1
devices=/dev/sda2,/dev/sdb2,/dev/sdc2,/dev/sdd2,/dev/sde2
ARRAY /dev/md0 level=raid1 num-devices=2 UUID=4b28338c:bf08d0bc:bb2899fc:e7f35eae
devices=/dev/sda1,/dev/sdd1
It was /dev/sdf that failed which contained two partitions, one of them part of md2 (now running un-mirrored but still showing two devices) and the other part of md5 (now re-syncing but only showing five devices).
Is this normal behaviour?
R. -- http://robinbowes.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
