Hi guys, >> Great, thanks for your offer to help. Great program you've written. >> I've included the output here: >> >> # mdadm -E /dev/sd[abcd][12] >> http://pastebin.com/3JcBjiV6 >> >> # When I booted into the rescue CD again, it mounted md0 as md127 >> http://pastebin.com/yXnzzL6K >> > > Hmmm ... looks like a bit of a mess. Two devices that should be active > arrays appear to be spares. I suspect you tried to --add them when you > shouldn't have. Newer version of mdadm stop you from doing that but older > version don't. You only --add a device that you want to be a spare, not a > device that you think is part of the array. Yes, that is what I did. > All of the devices think that device 2 (the third in the array) should exist > and be working, but no device claims to be it. Presumably it is /dev/sdc2. > > > You will need to recreate the array. > i.e. > > mdadm -S /dev/md1 > or > mdadm -S /dev/md125 /dev/md126 > > or whatever md arrays claim to be holding any of the 4 devices according > to /proc/mdstat. > > Then > > mdadm -C /dev/md1 -e 1.1 --level 5 -n 4 --chunk 512 --assume-clean \ > /dev/sda2 /dev/sdb2 /dev/sdc2 missing > > This will just re-write the metadata and assemble the array. It won't change > the data. > Then "fsck -n /dev/md1" and make sure it looks good. > If it does: good. > If not, try again with sdd2 in place of sdc2. > > Once you are happy that you can see your data, you can add the other device > as a spare and it will rebuild. Just wanted to let you know that these instructions worked perfectly, and thanks for all your help. Any idea how this would have happened in the first place? Somehow two of the three RAID5 devices failed at once. I've checked all the disks with the Fujitsu disk scanner, and it found no physical errors. I also don't think the disks were disturbed in any way while they were operating. Thanks again, Alex -- 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
