From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Robinson Subject: Re: RAID mirror, resyncing from bad disk Date: Mon, 14 Sep 2009 10:23:15 +0100 Message-ID: <4AAE0B83.8040009@anonymous.org.uk> References: <4AAD45AE.6060503@amazinginternet.com> <4AAD5510.2060505@anonymous.org.uk> <4AAE0930.1030204@amazinginternet.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4AAE0930.1030204@amazinginternet.com> Sender: linux-raid-owner@vger.kernel.org To: Ronny Adsetts Cc: Linux RAID ML List-Id: linux-raid.ids On 14/09/2009 10:13, Ronny Adsetts wrote: > John Robinson said at 13/09/2009 21:24: >> On 13/09/2009 20:19, Ronny Adsetts wrote: >> [...] >>> The problematic array is /dev/md2 and the dying disk is /dev/sdc. >>> >>> When I try to resync it gets to about 99.2% then gives load of I/O >>> errors in /var/log/kern.log and finally gives up and restarts the sync. >>> >>> Ideally I just want to tell the system to ignore the bad sector and >>> just resync the array. >>> >>> Does anyone have any ideas on how I can get this resolved short of >>> reinstalling? >> You need to ddrescue the contents of the dying drive onto a good one, >> then replace the dying drive with the fresh one. This will require >> taking the array down but you won't have to reinstall, unless you've >> lost something important in the lost sectors on the dying drive. > > The bad sector is thankfully right at the end of the disk in an unallocated part of the LVM setup. > > So, do I ddrescue the entire disk? I assume this will copy everything including the partition table and other gubbins? Yes you do, and yes it will. You don't have to use ddrescue, there are other tools - for examples see http://www.forensicswiki.org/wiki/Ddrescue - but ddrescue would be my choice. > Thanks very much, this looks like a winner to me. :-). Good luck with it! Cheers, John.