From mboxrd@z Thu Jan 1 00:00:00 1970 From: pg@lxra2.for.sabi.co.UK (Peter Grandi) Subject: Re: Advice please re failed Raid6 Date: Wed, 19 Jul 2017 13:36:56 +0100 Message-ID: <22895.21096.215892.928052@tree.ty.sabi.co.uk> References: <9dca5b7a-b60e-0e93-41fd-49d092d8b27b@gmail.com> <22892.649.826246.644975@tree.ty.sabi.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Linux Raid List-Id: linux-raid.ids > Did I do it right? (See below) > root@keruru:~# mdadm --create --assume-clean --level=6 --raid-devices=4 > --size=1953382912 /dev/md0 missing /dev/sdc /dev/sdd /dev/sde > mdadm: /dev/sdc appears to be part of a raid array: > level=raid6 devices=4 ctime=Tue Jul 11 17:33:12 2017 > mdadm: /dev/sdd appears to be part of a raid array: > level=raid6 devices=4 ctime=Tue Jul 11 17:33:12 2017 > mdadm: /dev/sde appears to be part of a raid array: > level=raid6 devices=4 ctime=Tue Jul 11 17:33:12 2017 > Continue creating array? y > mdadm: Defaulting to version 1.2 metadata > mdadm: array /dev/md0 started. This looks good, but is based on your original '--examine' report as to the order of the devices, and whether they are still bound to the same names 'sd[bcde]'. > root@keruru:~# blkid /dev/md0 > root@keruru:~# cat /proc/mdstat > Personalities : [raid6] [raid5] [raid4] > md0 : active (auto-read-only) raid6 sde[3] sdd[2] sdc[1] > 3906765824 blocks super 1.2 level 6, 512k chunk, algorithm 2 > [4/3] [_UUU] > unused devices: The 'mdstat' actually looks good, but 'blkid' should have worked. As I was saying, it is not clear to me whether the 'mdadm' daemon instance triggered a 'check' or a 'repair' (bad news). I hope that you disabled that in the meantime while you try to fix the mistake. Trigger a 'check' and see if the set is consistent; if it is consistent but the content cannot be read/mounted then 'repair' rewrote it, if it is not consistent, try a different order or 3-way subset of 'sd[bcde]'.