From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Berger Subject: Re: RAID 5 Recovery Help Needed Date: Fri, 16 Jan 2009 15:09:00 -0600 Message-ID: <4970F76C.2040500@mike01.com> References: <4970E18C.2000100@mike01.com> <4970F153.30106@scalableinformatics.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4970F153.30106@scalableinformatics.com> Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids Joe Landman wrote: > eek ... a RAID5 on 3 drives? I was planning on growing it as I needed more space and could afford more drives (scary, I know). > Did you do an > > mdadm --detail --scan > /etc/mdadm.conf > > after this? Unfortunately no. The guide I followed neglected to mention that step. > ... but did you update mdadm.conf as above? > This generally requires an /etc/mdadm.conf (or similar > /etc/mdadm/mdadm.conf) > You can often (re)construct this file if you forget to create it with > a little detective work ... > mdadm --examine /dev/sdb1 > could be your friend. > > [...] I did try putting the following into mdadm.conf manually after the reboot (and before doing the create again): DEVICES partitions ARRAY /dev/md0 UUID=3128da32:c5e4ff31:b43fc0e6:226924cf Then I tried to assemble it again (with scan), and still no luck. Unfortunately since the guide I used never mentioned the config file at all, and seeing "DEVICE partitions" in it, I assumed it was fine. I never gave it more thought until the second create failed to improve things. > >> # fsck.ext4 -n /dev/md0 >> >> I get: >> >> fsck.ext4: Superblock invalid, trying backup blocks... >> fsck.ext4: Bad magic number in super-block while trying to open /dev/md0 >> >> I've tried specifying the blocksize and specifying the superblock >> manually using the backup superblocks from when I ran mkfs.ext4, but >> get the same result. I haven't dared to run fsck without -n until I >> hear from someone more knowledged. >> >> So, if anyone has any suggestions on how I can get md0 mounted or >> recover my data it would be much appreciated. > > I am not completely sure, but I would bet that with the changes you > have made, that this data may not be recoverable at this point. > > Before you do anything else, I would definitely suggest creating the > mdadm.conf file properly as noted above. > > Joe > I've created an mdadm.conf file via 'mdadm --detail --scan', so assuming that was the original problem with the raid not being assembled properly before, that should be solved. The problem now lies in getting my data back if possible. I don't plan to assemble the array again or try anything else until I've given enough time for others wiser than I to respond. Thanks, Mike