On Sat, 02 Jul 2011 10:54:05 +0200 Petter Reinholdtsen <pere@xxxxxxxxxx> wrote: > > I could use some help with recovering a raid5. I had two RAID5 using > three disks. The 1T disks were partitioned into two halves and each > raid5 used one partition from each disk (created this way to be able > to add my 500G disks into the raids). > > Then I added two more disks to the setup, partitioned the same way, > and added their partitions to the two raids and asked the raids to > grow. The first raid started growing and got around 60% out before > the machine crashed and had to be rebooted. The second raid did not > start growing and was PENDING. As far as I know, it was still PENDING > when the machine crashed. When I ran mdadm to start the second > growing, the mdadm command hung waiting for the other grow operation > to finish. I ended up killing it after a few hours, hoping to > continue the grow operation when the first raid was done growing after > 15 days. > > After the crash and first reboot , the first raid5 is activated and > show up as auto-read-only, and the second raid fail to assemble. I > did not specify a backup file when growing, as the recipe I found did > not mention that it was smart to do. Now I wish I had. I probably wouldn't have helped. It is supposed to write backup stuff to the spares and if it didn't do that, it probably wouldn't have written it to a file either. The easiest fix for now is to recreate the array. mdadm -CR /dev/md3 --metadata=0.90 -n3 -l5 -c64 /dev/sdb2 /dev/sdc2 /dev/sdf2 --assume-clean should do it. Then if that looks good, add the extra devices and grow the array again. NeilBrown > > Any ideas how I can recover my raid? After reading > <URL: https://raid.wiki.kernel.org/index.php/RAID_Recovery >, I > suspect creating it again is the solution, but am unsure if I should > recreate it with 3 or 5 partitions. Trying to assembly result in this: > > meta:~# mdadm --assemble /dev/md3 /dev/sdd2 /dev/sde2 /dev/sdh2 /dev/sda2 /dev/sdb2 > mdadm: Failed to restore critical section for reshape, sorry. > Possibly you needed to specify the --backup-file > meta:~# > > How can I know which disks to use when recreating if I want to > recreate using only three disks? Is it the three with the active > state? > > This is the content of /proc/mdstat. The md0 and md1 RAIDs can be > ignored as they are on two different disks: > > Personalities : [raid1] [raid6] [raid5] [raid4] > md2 : active (auto-read-only) raid5 sdd1[0] sda1[4] sdb1[3] sde1[2] sdh1[1] > 976558976 blocks super 0.91 level 5, 64k chunk, algorithm 2 [5/5] [UUUUU] > > md1 : active raid1 sdc2[0] sdf2[1] > 976510912 blocks [2/2] [UU] > > md0 : active raid1 sdc1[0] sdf1[1] > 248896 blocks [2/2] [UU] > > unused devices: <none> > > Based on the disks used by md2, I ran "mdadm --examine > /dev/sd[dabeh]2" to get the status of the problematic partitions: > > /dev/sda2: > Magic : a92b4efc > Version : 00.91.00 > UUID : 6dcd10c1:39d083f9:e49659ac:48e50bf6 > Creation Time : Sun Oct 26 17:29:27 2008 > Raid Level : raid5 > Used Dev Size : 488279488 (465.66 GiB 500.00 GB) > Array Size : 1953117952 (1862.64 GiB 1999.99 GB) > Raid Devices : 5 > Total Devices : 5 > Preferred Minor : 3 > > Reshape pos'n : 0 > Delta Devices : 2 (3->5) > > Update Time : Thu Jun 30 11:00:18 2011 > State : active > Active Devices : 5 > Working Devices : 5 > Failed Devices : 0 > Spare Devices : 0 > Checksum : 3274a54b - correct > Events : 193913 > > Layout : left-symmetric > Chunk Size : 64K > > Number Major Minor RaidDevice State > this 4 8 98 4 active sync > > 0 0 8 18 0 active sync /dev/sdb2 > 1 1 8 34 1 active sync /dev/sdc2 > 2 2 8 82 2 active sync /dev/sdf2 > 3 3 8 114 3 active sync /dev/sdh2 > 4 4 8 98 4 active sync > /dev/sdb2: > Magic : a92b4efc > Version : 00.91.00 > UUID : 6dcd10c1:39d083f9:e49659ac:48e50bf6 > Creation Time : Sun Oct 26 17:29:27 2008 > Raid Level : raid5 > Used Dev Size : 488279488 (465.66 GiB 500.00 GB) > Array Size : 1953117952 (1862.64 GiB 1999.99 GB) > Raid Devices : 5 > Total Devices : 5 > Preferred Minor : 3 > > Reshape pos'n : 0 > Delta Devices : 2 (3->5) > > Update Time : Thu Jun 30 11:00:18 2011 > State : active > Active Devices : 5 > Working Devices : 5 > Failed Devices : 0 > Spare Devices : 0 > Checksum : 3274a559 - correct > Events : 193913 > > Layout : left-symmetric > Chunk Size : 64K > > Number Major Minor RaidDevice State > this 3 8 114 3 active sync /dev/sdh2 > > 0 0 8 18 0 active sync /dev/sdb2 > 1 1 8 34 1 active sync /dev/sdc2 > 2 2 8 82 2 active sync /dev/sdf2 > 3 3 8 114 3 active sync /dev/sdh2 > 4 4 8 98 4 active sync > /dev/sdd2: > Magic : a92b4efc > Version : 00.91.00 > UUID : 6dcd10c1:39d083f9:e49659ac:48e50bf6 > Creation Time : Sun Oct 26 17:29:27 2008 > Raid Level : raid5 > Used Dev Size : 488279488 (465.66 GiB 500.00 GB) > Array Size : 1953117952 (1862.64 GiB 1999.99 GB) > Raid Devices : 5 > Total Devices : 5 > Preferred Minor : 3 > > Reshape pos'n : 0 > Delta Devices : 2 (3->5) > > Update Time : Thu Jun 30 10:59:48 2011 > State : clean > Active Devices : 5 > Working Devices : 5 > Failed Devices : 0 > Spare Devices : 0 > Checksum : 32779a4d - correct > Events : 193912 > > Layout : left-symmetric > Chunk Size : 64K > > Number Major Minor RaidDevice State > this 0 8 18 0 active sync /dev/sdb2 > > 0 0 8 18 0 active sync /dev/sdb2 > 1 1 8 34 1 active sync /dev/sdc2 > 2 2 8 82 2 active sync /dev/sdf2 > 3 3 8 114 3 active sync /dev/sdh2 > 4 4 8 98 4 active sync > /dev/sde2: > Magic : a92b4efc > Version : 00.91.00 > UUID : 6dcd10c1:39d083f9:e49659ac:48e50bf6 > Creation Time : Sun Oct 26 17:29:27 2008 > Raid Level : raid5 > Used Dev Size : 488279488 (465.66 GiB 500.00 GB) > Array Size : 1953117952 (1862.64 GiB 1999.99 GB) > Raid Devices : 5 > Total Devices : 5 > Preferred Minor : 3 > > Reshape pos'n : 0 > Delta Devices : 2 (3->5) > > Update Time : Thu Jun 30 11:00:18 2011 > State : active > Active Devices : 5 > Working Devices : 5 > Failed Devices : 0 > Spare Devices : 0 > Checksum : 3274a505 - correct > Events : 193913 > > Layout : left-symmetric > Chunk Size : 64K > > Number Major Minor RaidDevice State > this 1 8 34 1 active sync /dev/sdc2 > > 0 0 8 18 0 active sync /dev/sdb2 > 1 1 8 34 1 active sync /dev/sdc2 > 2 2 8 82 2 active sync /dev/sdf2 > 3 3 8 114 3 active sync /dev/sdh2 > 4 4 8 98 4 active sync > /dev/sdh2: > Magic : a92b4efc > Version : 00.91.00 > UUID : 6dcd10c1:39d083f9:e49659ac:48e50bf6 > Creation Time : Sun Oct 26 17:29:27 2008 > Raid Level : raid5 > Used Dev Size : 488279488 (465.66 GiB 500.00 GB) > Array Size : 1953117952 (1862.64 GiB 1999.99 GB) > Raid Devices : 5 > Total Devices : 5 > Preferred Minor : 3 > > Reshape pos'n : 0 > Delta Devices : 2 (3->5) > > Update Time : Thu Jun 30 10:59:48 2011 > State : clean > Active Devices : 5 > Working Devices : 5 > Failed Devices : 0 > Spare Devices : 0 > Checksum : 32779a91 - correct > Events : 193912 > > Layout : left-symmetric > Chunk Size : 64K > > Number Major Minor RaidDevice State > this 2 8 82 2 active sync /dev/sdf2 > > 0 0 8 18 0 active sync /dev/sdb2 > 1 1 8 34 1 active sync /dev/sdc2 > 2 2 8 82 2 active sync /dev/sdf2 > 3 3 8 114 3 active sync /dev/sdh2 > 4 4 8 98 4 active sync > > Happy hacking, -- 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
