Re: RAID 5 array recovery - two drives errors in external enclosure
flat view
From: Tim Bostrom <hidden>
Date: 2009-09-18 15:27:08
Is there any mdadm command that would have given any info or metadata from the previous array? I have almost 9 months of SSH logging on my laptop that I use to manage the array. Maybe there's some useful info left in the log that might help. -Tim On Fri, Sep 18, 2009 at 1:07 AM, Robin Hill [off-list ref] wrote:
On Thu Sep 17, 2009 at 09:19:58PM -0700, Tim Bostrom wrote:quoted
This seemed to work, though I'm still working through the permutations of the drive letters. I noticed that mdadm think that partition sde1 is ext2 filesystem on it. See below: [root@tera tbostrom]# mdadm -C /dev/md0 -l 5 -n 5 -c 256 /dev/sdb1 /dev/sdd1 /dev/sdc1 /dev/sde1 missing mdadm: /dev/sdb1 appears to be part of a raid array: level=raid5 devices=5 ctime=Thu Sep 17 21:13:21 2009 mdadm: /dev/sdd1 appears to be part of a raid array: level=raid5 devices=5 ctime=Thu Sep 17 21:13:21 2009 mdadm: /dev/sdc1 appears to be part of a raid array: level=raid5 devices=5 ctime=Thu Sep 17 21:13:21 2009 mdadm: /dev/sde1 appears to contain an ext2fs file system size=396408836K mtime=Mon Sep 21 03:41:16 2026 mdadm: /dev/sde1 appears to be part of a raid array: level=raid5 devices=5 ctime=Thu Sep 17 21:13:21 2009 Continue creating array? What gives? I tried popping sdf1 in there without creating the array - just to see what would happen and it thinks that sdf1 has ext2 as well.That would suggest that sde1 is the first disk in the array (I think).quoted
Still at a loss here. I haven't worked through all the drive permutations. In the meantime, I'll try that. Does it make sense to try sdf1 in the permutation since the drive letters may have changed since moving from the enclosure? I thought I put them back in the same order as the enclosure.Definitely not - we know sdf1 has been re-written when you did the initial --create after moving the drives out of the enclosure. This means it _definitely_ has invalid data on it. Unfortunately, without having the metadata information from the _original_ array _after_ it has been moved from the enclosure, there's no way of knowing what order the drives should be in. I _think_ that sde1 will be the first disk (as it shows up as an ext2 filesystem), but you'll really have to try every possible combination of the 5 devices (the 4 partitions and "missing"). You may be best scripting this (or searching to see whether someone's already done that) - there's 120 possible combinations to try. Cheers, Robin -- ___ ( ' } | Robin Hill [off-list ref] | / / ) | Little Jim says .... | // !! | "He fallen in de water !!" |
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