On Mar 12, 2011, at 8:56 PM, Phil Turmel wrote: > On 03/12/2011 10:38 PM, mtice wrote: >> Hi Phil, thanks for the reply. >> Here is the output of mdadm -E /dev/sd[cdef] >> >> /dev/sdc: >> Magic : a92b4efc >> Version : 00.90.00 >> UUID : 11c1cdd8:60ec9a90:2e29483d:f114274d (local to host storage) >> Creation Time : Thu May 27 15:35:56 2010 >> Raid Level : raid5 >> Used Dev Size : 732574464 (698.64 GiB 750.16 GB) >> Array Size : 2197723392 (2095.91 GiB 2250.47 GB) >> Raid Devices : 4 >> Total Devices : 5 >> Preferred Minor : 0 >> >> Update Time : Fri Mar 11 15:53:35 2011 >> State : clean >> Active Devices : 2 >> Working Devices : 4 >> Failed Devices : 2 >> Spare Devices : 2 >> Checksum : 3d3b86 - correct >> Events : 43200 >> >> Layout : left-symmetric >> Chunk Size : 64K >> >> Number Major Minor RaidDevice State >> this 3 8 32 3 active sync /dev/sdc >> >> 0 0 8 80 0 active sync /dev/sdf >> 1 1 0 0 1 faulty removed >> 2 2 0 0 2 faulty removed >> 3 3 8 32 3 active sync /dev/sdc >> 4 4 8 64 4 spare /dev/sde >> 5 5 8 112 5 spare >> /dev/sdd: >> Magic : a92b4efc >> Version : 00.90.00 >> UUID : 11c1cdd8:60ec9a90:2e29483d:f114274d (local to host storage) >> Creation Time : Thu May 27 15:35:56 2010 >> Raid Level : raid5 >> Used Dev Size : 732574464 (698.64 GiB 750.16 GB) >> Array Size : 2197723392 (2095.91 GiB 2250.47 GB) >> Raid Devices : 4 >> Total Devices : 5 >> Preferred Minor : 0 >> >> Update Time : Fri Mar 11 15:53:35 2011 >> State : clean >> Active Devices : 2 >> Working Devices : 4 >> Failed Devices : 2 >> Spare Devices : 2 >> Checksum : 3d3bd4 - correct >> Events : 43200 >> >> Layout : left-symmetric >> Chunk Size : 64K >> >> Number Major Minor RaidDevice State >> this 5 8 112 5 spare >> >> 0 0 8 80 0 active sync /dev/sdf >> 1 1 0 0 1 faulty removed >> 2 2 0 0 2 faulty removed >> 3 3 8 32 3 active sync /dev/sdc >> 4 4 8 64 4 spare /dev/sde >> 5 5 8 112 5 spare >> /dev/sde: >> Magic : a92b4efc >> Version : 00.90.00 >> UUID : 11c1cdd8:60ec9a90:2e29483d:f114274d (local to host storage) >> Creation Time : Thu May 27 15:35:56 2010 >> Raid Level : raid5 >> Used Dev Size : 732574464 (698.64 GiB 750.16 GB) >> Array Size : 2197723392 (2095.91 GiB 2250.47 GB) >> Raid Devices : 4 >> Total Devices : 5 >> Preferred Minor : 0 >> >> Update Time : Fri Mar 11 15:53:35 2011 >> State : clean >> Active Devices : 2 >> Working Devices : 4 >> Failed Devices : 2 >> Spare Devices : 2 >> Checksum : 3d3ba2 - correct >> Events : 43200 >> >> Layout : left-symmetric >> Chunk Size : 64K >> >> Number Major Minor RaidDevice State >> this 4 8 64 4 spare /dev/sde >> >> 0 0 8 80 0 active sync /dev/sdf >> 1 1 0 0 1 faulty removed >> 2 2 0 0 2 faulty removed >> 3 3 8 32 3 active sync /dev/sdc >> 4 4 8 64 4 spare /dev/sde >> 5 5 8 112 5 spare >> /dev/sdf: >> Magic : a92b4efc >> Version : 00.90.00 >> UUID : 11c1cdd8:60ec9a90:2e29483d:f114274d (local to host storage) >> Creation Time : Thu May 27 15:35:56 2010 >> Raid Level : raid5 >> Used Dev Size : 732574464 (698.64 GiB 750.16 GB) >> Array Size : 2197723392 (2095.91 GiB 2250.47 GB) >> Raid Devices : 4 >> Total Devices : 5 >> Preferred Minor : 0 >> >> Update Time : Fri Mar 11 15:53:35 2011 >> State : clean >> Active Devices : 2 >> Working Devices : 4 >> Failed Devices : 2 >> Spare Devices : 2 >> Checksum : 3d3bb0 - correct >> Events : 43200 >> >> Layout : left-symmetric >> Chunk Size : 64K >> >> Number Major Minor RaidDevice State >> this 0 8 80 0 active sync /dev/sdf >> >> 0 0 8 80 0 active sync /dev/sdf >> 1 1 0 0 1 faulty removed >> 2 2 0 0 2 faulty removed >> 3 3 8 32 3 active sync /dev/sdc >> 4 4 8 64 4 spare /dev/sde >> 5 5 8 112 5 spare >> >> >> I ran mdadm --assemble --force /dev/md0 but it erred with: >> >> mdadm: device /dev/md0 already active - cannot assemble it > > You would have to stop the array first. But it won't matter. The dropped devices don't remember their role. But you have a 50-50 chance of getting it right. It's either: > > mdadm --create /dev/md0 --level=5 --raid-devices=4 --assume-clean --metadata=0.90 --chunk=64k /dev/sdf /dev/sde /dev/sdd /dev/sdc > > or with /dev/sde and /dev/sdd swapped. > > I suggest you try it both ways, with an "fsck -n" to see which has a consistent filesystem. Once you figure out which order is correct, do a real fsck to fix up any minor errors from the inadvertent unplug, then mount and grab a fresh backup. > > Let us know how it turns out (I'm about to sign off for the night...). > > Phil That did it. Thanks, Phil! I was able to get the drives added back in with: mdadm --create /dev/md0 --level=5 --raid-devices=4 --assume-clean --metadata=0.90 --chunk=64 /dev/sdf /dev/sde /dev/sdd /dev/sdc An fsck -n came back clean so I ran another fsck and mounted it up and all looks good. Thanks for your help! Matt -- 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
