Hi Thomas, On 02/10/2011 01:03 PM, Thomas Heilberg wrote: > Hi! > > Sorry for my bad English. I'm from Austria and this is also my first "mailinglist-post". Welcome! (Your English looks fine to me--and I've had 40+ years of practice.) > > I have a problem with my RAID5. The raid has only 1 active devices out of 3. The other 2 devices are detected as spare. > This is what happens when I try to assemble the raid(I'm using loop devices because I'm working with backup files): Working from backups is a very good plan! > root@backup-server:/media# mdadm --assemble --force /dev/md2 /dev/loop0 /dev/loop1 /dev/loop2 > mdadm: /dev/md2 assembled from 1 drive and 2 spares - not enough to start the array. > > root@backup-server:/media# cat /proc/mdstat > Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] > md2 : inactive loop1[0](S) loop2[4](S) loop0[3](S) > 4390443648 blocks > > unused devices: <none> > > root@backup-server:/media# mdadm -R /dev/md2 > mdadm: failed to run array /dev/md2: Input/output error > > root@backup-server:/media# mdadm -D /dev/md2 > /dev/md2: > Version : 0.90 > Creation Time : Thu Nov 19 21:09:37 2009 > Raid Level : raid5 > Used Dev Size : 1463481216 (1395.68 GiB 1498.60 GB) > Raid Devices : 3 > Total Devices : 1 > Preferred Minor : 2 > Persistence : Superblock is persistent > > Update Time : Sun Nov 14 14:12:44 2010 > State : active, FAILED, Not Started > Active Devices : 1 > Working Devices : 1 > Failed Devices : 0 > Spare Devices : 0 > > Layout : left-symmetric > Chunk Size : 64K > > UUID : 9665c475:31f17aa2:83a3570a:c5b3b84e > Events : 0.3352467 > > Number Major Minor RaidDevice State > 0 7 1 0 active sync /dev/loop1 > 1 0 0 1 removed > 2 0 0 2 removed Hmmm. Not enough info here, and further steps destroy it. Good thing you started over. Please show "mdadm -E /dev/loop[0-2]" on fresh loop copies *before* trying any "create" or "add" operations. > root@backup-server:/media# mdadm /dev/md2 -a /dev/loop0 > mdadm: re-added /dev/loop0 > root@backup-server:/media# mdadm /dev/md2 -a /dev/loop2 > mdadm: re-added /dev/loop2 > root@backup-server:/media# mdadm -D /dev/md2 > /dev/md2: > Version : 0.90 > Creation Time : Thu Nov 19 21:09:37 2009 > Raid Level : raid5 > Used Dev Size : 1463481216 (1395.68 GiB 1498.60 GB) > Raid Devices : 3 > Total Devices : 3 > Preferred Minor : 2 > Persistence : Superblock is persistent > > Update Time : Sun Nov 14 14:12:44 2010 > State : active, FAILED, Not Started > Active Devices : 1 > Working Devices : 3 > Failed Devices : 0 > Spare Devices : 2 > > Layout : left-symmetric > Chunk Size : 64K > > UUID : 9665c475:31f17aa2:83a3570a:c5b3b84e > Events : 0.3352467 > > Number Major Minor RaidDevice State > 0 7 1 0 active sync /dev/loop1 > 1 0 0 1 removed > 2 0 0 2 removed > > 3 7 0 - spare /dev/loop0 > 4 7 2 - spare /dev/loop2 > > I also tried to recreate the raid: > > root@backup-server:/media# mdadm -Cv /dev/md2 -n3 -l5 /dev/loop0 /dev/loop1 /dev/loop2 > mdadm: layout defaults to left-symmetric > mdadm: chunk size defaults to 512K > mdadm: layout defaults to left-symmetric > mdadm: layout defaults to left-symmetric > mdadm: /dev/loop0 appears to be part of a raid array: > level=raid5 devices=3 ctime=Thu Nov 19 21:09:37 2009 > mdadm: layout defaults to left-symmetric > mdadm: /dev/loop1 appears to be part of a raid array: > level=raid5 devices=3 ctime=Thu Nov 19 21:09:37 2009 > mdadm: layout defaults to left-symmetric > mdadm: /dev/loop2 appears to be part of a raid array: > level=raid5 devices=3 ctime=Thu Nov 19 21:09:37 2009 > mdadm: size set to 1463479808K > Continue creating array? y > mdadm: Defaulting to version 1.2 metadata > mdadm: array /dev/md2 started. Yeah, mdadm was trying to tell you not to do that. "--assume-clean" is really important when trying to recreate an array with existing data. [trim /] If the problem is just the event counts, "mdadm --assemble --force" is probably what you want, followed by "mdadm --readonly". If pvscan shows your LVM subsystem at that point, try an fsck to see how much trouble you are in. Phil -- 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
