From mboxrd@z Thu Jan 1 00:00:00 1970 From: Neil Brown Subject: Re: Raid 5 to raid 6 reshape failure after reboot Date: Thu, 22 Oct 2009 10:44:53 +1100 Message-ID: <19167.40181.250468.925659@notabene.brown> References: <20091018181033.0255346c@borg.bxl.tuxicoman.be> <358606dfd356518f7fa42219f26082d2.squirrel@neil.brown.name> <20091019155322.65b4287f@zombie> <5744c797713398f21b00e5323ddeac1e.squirrel@neil.brown.name> <20091020103731.5dc611ff@zombie> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: message from Guy Martin on Tuesday October 20 Sender: linux-raid-owner@vger.kernel.org To: Guy Martin Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids On Tuesday October 20, gmsoft@tuxicoman.be wrote: > > Hi Neil, > > Here is the output I've got : > > bleh mdadm # ./mdadm --assemble /dev/md0 /dev/sd[bdef]1 --backup-file > backup -v mdadm: looking for devices for /dev/md0 > mdadm: /dev/sdb1 is identified as a member of /dev/md0, slot 0. > mdadm: /dev/sdd1 is identified as a member of /dev/md0, slot 1. > mdadm: /dev/sde1 is identified as a member of /dev/md0, slot 3. > mdadm: /dev/sdf1 is identified as a member of /dev/md0, slot 2. > mdadm:/dev/md0 has an active reshape - checking if critical section > needs to be restored mdadm: too-old timestamp on backup-metadata on > backup mdadm: Failed to find backup of critical section Ahhh... I wondered a bit about that as I was adding the fprintf there, but it was along the lines of "this cannot happen", not "this is where the bug might be" :-) I see now what is happening. I need to update the mtime every time I write the backup metadata (of course!). I never tripped on this because I never let a reshape run for more than a few minutes. I have checked in a patch which updated the mtime properly, so it should now word for you. Thanks for helping make mdadm even better! NeilBrown > mdadm: Failed to restore critical section for reshape, sorry. > > The backup file is of course the one I've been using for the grow > command. > > The values I've got : > - info->array.utime : 1256026602 > - bsb.mtime : 1256020033 > > My timezone is Europe/Brussels if that matters. > > Removing this check makes the reshape continue and the array start > correctly. > > Let me know if you want me to do some more tests. > > HTH, > Guy > > > On Tue, 20 Oct 2009 16:54:43 +1100 > "NeilBrown" wrote: > > > I tried to reproduce this and failed - it works perfectly for me. > > > > I have added some more tracing messages to --assemble which are > > enabled by --verbose. > > Could you please pull the latest devel-3.1 branch from my git tree and > > try the same assemble command but with --verbose at the end and > > report the result. > > > > Thanks. > > NeilBrown > >