From mboxrd@z Thu Jan 1 00:00:00 1970 From: Phil Turmel Subject: Re: Fwd: Help with failed RAID-5 -> 6 migration Date: Thu, 13 Jun 2013 10:09:17 -0400 Message-ID: <51B9D28D.8040702@turmel.org> References: <51B3B7FF.9080800@turmel.org> <51B62A8A.9070108@turmel.org> <51B6FF7E.1000707@turmel.org> <51B88AB2.5060303@turmel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Keith Phillips Cc: linux-raid List-Id: linux-raid.ids On 06/13/2013 09:58 AM, Keith Phillips wrote: >> You won't be able to assemble and run your array without a backup file. >> You said you lost your original, so you will have to use a blank one >> and tell mdadm to ignore the invalid file. > > Ah, didn't realise this was an option. After a brief googling it seems > my version of mdadm pre-dated the "--invalid-backup" option. > > Cloned the git repo and built a newer version, and re-assembled with > an empty "--backup-file" and the "--invalid-backup" option. Now it's > chugging along happily again - at %20 and counting now, no errors in > sight! Good to hear. :-) > Will do an ext4 fsck once it's finished the grow. Are there any tips > for determining what data I trashed by losing the backup-file? Or is > it just a case of trying to access stuff and seeing what's broken? You have the reshape position where the process stopped in the original mdadm -E reports. Use that to query for inodes that contain those sectors, then look up those inodes. A quick google came up with: http://smartmontools.sourceforge.net/badblockhowto.html You'll have to reinterpret that to use the sector offsets in your array rather than sector offset from smartctl. > Thanks so much for the help, Phil :) You're welcome. Phil