On 08/10/16 13:30, Andreas Klauer wrote: > On Fri, Oct 07, 2016 at 05:37:32PM +0200, Santiago DIEZ wrote: >> > First thing I did is ddrescue the remaining partitions sd[abc]10 . >> > ddrescue did not stumble into any read error so I assume all remaining >> > partitions are perfectly safe. > So ... don't you still have a good copy? > > You only killed one of them, right? Did not make same mistake twice? > >> > There comes my mistake: I ran the --create command instead of --assemble : >> > >> > ================================================================================ >> > # mdadm --create --verbose /dev/md1 --raid-devices=4 --level=raid5 >> > --run --readonly /dev/loop0 /dev/loop1 /dev/loop2 missing One oddity I've noticed. You've created the array using loop devices. What are these? The reason I ask is that using loopback devices is a standard technique for rebuilding a damaged array, specifically to prevent md from actually writing to the drive. So is it possible that "mdadm --create" only wrote to ram, and a reboot will recover your ddrescue copies untouched? My raid-fu isn't enough to tell me whether I'm right or not ... :-) If necessary you'll have to do another ddrescue from the original drives, and you should then be able to assemble the array from the copies. Don't use "missing", use "--force" and you should get a working, degraded, array to which you can add a new drive and rebuild the array. mdadm --assemble /dev/md0 /dev/sd[efg]10 --force if I'm right ... so long as it's the copies, you can always recover again from the original disks, and if there's a problem with the copies mdadm should complain when it assembles the array. Cheers, Wol -- 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
