From mboxrd@z Thu Jan 1 00:00:00 1970 From: "P. Gautschi" Subject: Re: Raid5 drive fail during grow and no backup Date: Fri, 07 Nov 2014 17:06:19 +0100 Message-ID: <545CEDFB.6060806@gautschi.net> References: <5455A35C.2060000@turmel.org> <5458FC2A.1050308@turmel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <5458FC2A.1050308@turmel.org> Sender: linux-raid-owner@vger.kernel.org To: Phil Turmel Cc: Vince , linux-raid@vger.kernel.org List-Id: linux-raid.ids > This is a problem you haven't solved yet, I think. The raid array should have fixed this bad sector for you without kicking the drive out. The scenario is common with "green" drives and/or consumer-grade drives in general. > ... > Then you can set up your array to properly correct bad sectors, and set your system to look for bad sectors on > a regular basis. What is the behavior of mdadm when a disk reports a read error? - reconstruct the data, deliver it to the fs and otherwise ignore it? - set the disk to fail? - reconstruct the data, rewrite the failed data and continue with any action? - rewrite the failed data and reread it (bypassing the cache on the HD)? Do read operation always read the parity too in order to detect problems early before a sector on a other disks fails? Can the behavior be configured in any way? I found no documentation regarding this. Patrick