From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Rabbitson Subject: Re: Suggestion needed for fixing RAID6 Date: Thu, 22 Apr 2010 18:32:17 +0200 Message-ID: <4BD07A11.5040300@rabbit.us> References: <626601cae203$dae35030$0400a8c0@dcccs> <64bd01cae22e$456461e0$0400a8c0@dcccs> 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: Mikael Abrahamsson Cc: Janos Haar , linux-raid@vger.kernel.org List-Id: linux-raid.ids Mikael Abrahamsson wrote: > On Thu, 22 Apr 2010, Janos Haar wrote: > > I don't have a good idea that assures your data, unfortunately. One way > would be to dd the defective drives to working ones, but that will most > likely cause you to have data loss on the defective sectors (since md > has no idea that these sectors should be re-created from parity). > There was a thread[1] some time ago, where HPA confirmed that the RAID6 data is sufficient to write an algorithm which will be able to determine which sector is in fact the offending one. There wasn't any interest to incorporate this into the sync_action/repair function though :( [1] http://www.mail-archive.com/linux-raid@vger.kernel.org/msg07327.html