From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Teytelman Subject: Re: Can this setup be saved? Date: Mon, 15 Feb 2010 06:02:56 -0800 Message-ID: References: <4877c76c1002121813h410900by1c398c80e2aa0635@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: <4877c76c1002121813h410900by1c398c80e2aa0635@mail.gmail.com> Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids Hello all, On Fri, Feb 12, 2010 at 18:13, Michael Evans wrote: > On Fri, Feb 12, 2010 at 5:56 PM, Dmitry Teytelman wrote: >> >> However at some point during/after the reconstruction the situation >> has changed. Now both /dev/sdc2 and /dev/sdd2 are marked as spare >> drives (see mdadm -E output below) and I cannot start the array. I >> think /dev/sdd2 should be in sync with /dev/sda2, but how can I bring >> it back (it used to be device 2)? > > It sounds like you've reached the point where you've done something > silly and need to try to recover what you can. > > READ THIS SITE CAREFULLY; perform READ ONLY recovery, and see if you > can find a permutation that can be mounted read only and READ with > valid data; I am back on the air!!! Th critical step was the use of "mdadm --create" with a missing drive. I knew the proper order for the two drives that were in sync. One of them (/dev/sdd) was failing, so it was ddrescue-d onto a new drive prior to any repairs. Performing "mdadm --create" brought the RAID device back to life. I checked that the data looked OK (read-only). Then I went ahead and added the third drive to the array. Soon a fully reconstructed device was up and running. Failed drives are heading back to Hitachi :) Thanks to the group for rapid response and critically important bits of information! -- Dmitry Teytelman