From mboxrd@z Thu Jan 1 00:00:00 1970 From: Reindl Harald Subject: Re: Filesystem corruption on RAID1 Date: Fri, 1 Sep 2017 07:39:38 +0200 Message-ID: <8fa7e6e8-0924-6db7-2e7d-9d5316cb3b8e@thelounge.net> References: <20170713214856.4a5c8778@natsu> <592f19bf608e9a959f9445f7f25c5dad@assyoma.it> <770b09d3-cff6-b6b2-0a51-5d11e8bac7e9@thelounge.net> <9eea45ddc0f80f4f4e238b5c2527a1fa@assyoma.it> <7ca98351facca6e3668d3271422e1376@assyoma.it> <5995D377.9080100@youngman.org.uk> <83f4572f09e7fbab9d4e6de4a5257232@assyoma.it> <59961DD7.3060208@youngman.org.uk> <784bec391a00b9e074744f31901df636@assyoma.it> <7d0af770699948fb0ecb66185145be05@assyoma.it> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Content-Language: de-CH Sender: linux-raid-owner@vger.kernel.org To: Linux RAID List-Id: linux-raid.ids Am 01.09.2017 um 00:55 schrieb Robert L Mathews: > On 8/20/17 3:43 AM, Mikael Abrahamsson wrote: > >> Indeed, but as far as I know there is nothing md can do about this. What >> md could do about it is at least present a consistent view of data to >> fsck (which for raid1 would be read all stripes and issue "repair" if >> they don't match). Yes, this might indeed cause corruption but at least >> it would be consistent and visible. > > If you set all disks except one as "write-mostly", won't mdadm give you > a consistent view of it because it only reads from a single disk? you gain nothing when you completly lie to fsck and after that switch back to normal operations with the other disks part of the game and it works only on RAID1 and *really* RAID1, otherwise my current RAID10 would be as fast as hell instead the terrible random lags which are worser sometimes as before replace two out of 4 disks with a SSD