I forced the three good disks and the one that was behind by two events to assemble: mdadm --assemble --force /dev/md0 /dev/sda2 /dev/sdb2 /dev/sdc2 /dev/sde2 Then I added the other two disks and let it sync overnight: mdadm --add --force /dev/md0 /dev/sdd2 mdadm --add --force /dev/md0 /dev/sdf2 I rebooted the system in recovery mode and the root filesystem is back! However, / is read-only and my /srv partition, which is the largest and has most of my data, can't mount. When I try to examine the array, it says "no md superblock detected on /dev/md0." On top of the software RAID, I have four logical volumes. Here is the full LVM configuration: http://pastebin.com/gzdZq5DL How do I recover the superblock? On Sun, Sep 21, 2014 at 10:47 PM, NeilBrown <neilb@xxxxxxx> wrote: > On Sun, 21 Sep 2014 22:32:19 -0700 Ian Young <ian@xxxxxxxxxxxxxxx> wrote: > >> My 6-drive software RAID 10 array failed. The individual drives >> failed one at a time over the past few months but it's been an >> extremely busy summer and I didn't have the free time to RMA the >> drives and rebuild the array. Now I'm wishing I had acted sooner >> because three of the drives are marked as removed and the array >> doesn't have enough mirrors to start. I followed the recovery >> instructions at raid.wiki.kernel.org and, before making things any >> worse, saved the status using mdadm --examine and consulted this >> mailing list. Here's the status: >> >> http://pastebin.com/KkV8e8Gq >> >> I can see that the event counts on sdd2 and sdf2 are significantly far >> behind, so we can consider that data too old. sdc2 is only behind by >> two events, so any data loss there should be minimal. If I can make >> the array start with sd[abce]2 I think that will be enough to mount >> the filesystem, back up my data, and start replacing drives. How do I >> do that? > > Use the "--force" option with "--assemble". > > NeilBrown -- 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
