From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wols Lists Subject: Re: Why can't I re-add my drive after partition shrink? Date: Thu, 20 Jul 2017 11:23:46 +0100 Message-ID: <597084B2.7030205@youngman.org.uk> References: <2ea5ed99-05b5-25d2-c9d4-8ce1f4945eaa@gmail.com> <87tw2f2425.fsf@notabene.neil.brown.name> <0341a04d-9aa5-7665-d9ff-527fe9fc8238@gmail.com> <87pod0ypmh.fsf@notabene.neil.brown.name> <8d3e1264-2f0a-6ee9-52b5-edddc1e6f185@gmail.com> <87fudsxbmz.fsf@notabene.neil.brown.name> <05a2d9b7-3b6a-2b49-53ad-3436061558fc@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <05a2d9b7-3b6a-2b49-53ad-3436061558fc@gmail.com> Sender: linux-raid-owner@vger.kernel.org To: Ram Ramesh , NeilBrown , Linux Raid List-Id: linux-raid.ids On 20/07/17 01:39, Ram Ramesh wrote: > On 07/19/2017 06:14 PM, NeilBrown wrote: >> On Wed, Jul 19 2017, Ram Ramesh wrote: >> >>> Here is my attempt to repeat the steps in my last attempt to remove, >>> repartition, re-add. Last time I did it on /dev/sdb. Now I am going to >>> do it on /dev/sdc. Note that I have not been successful as you see at >>> the end. I am going to keep the array degraded so that I can still get >>> old info from /dev/sdc1, if you need anything else. I will keep it this >>> way till tomorrow and then add the device for md to rebuild. Please ask >>> anything else before that or send me a note to keep the array degraded >>> so that you can examine /dev/sdc1 more. >> Thanks. I *love* getting all the details. You cannot send too many >> details! >> >> This: >>> >>>> zym [rramesh] 265 > sudo mdadm --examine /dev/sdb1 >>>> /dev/sdb1: >> .. >>>> Avail Dev Size : 6442188800 (3071.88 GiB 3298.40 GB) >> and this: >> >>> >>>> zym [rramesh] 267 > sudo mdadm --examine /dev/sdc1 >>>> /dev/sdc1: >> ... >>>> Avail Dev Size : 11720780943 (5588.90 GiB 6001.04 GB) >> Shows the key difference. "Avail Dev Size", aka sb->data_size, is >> wrong. We can fix it. >> >>> >>>> zym [rramesh] 270 > sudo mdadm /dev/md0 --re-add /dev/sdc1 >>>> mdadm: --re-add for /dev/sdc1 to /dev/md0 is not possible >> Please try >> sudo mdadm /dev/md0 --re-add /dev/sdc1 --update=devicesize >> >> Thanks, >> NeilBrown > > Neil, > > Thanks a ton. That does it. It got re-added without any issue. It is > rebuilding because the array was used to record two TV programs when it > was in degraded state. But the re-add is accepted. > >> zym [rramesh] 274 > sudo mdadm /dev/md0 --re-add /dev/sdc1 >> --update=devicesize >> Size was 11720780943 >> Size is 6442188800 >> mdadm: re-added /dev/sdc1 >> zym [rramesh] 275 > cat /proc/mdstat >> Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] >> [raid4] [raid10] >> md0 : active raid6 sdc1[10] sdb1[6] sdg1[11] sdd1[12] sdf1[8] sde1[9] >> 12348030976 blocks super 1.2 level 6, 64k chunk, algorithm 2 >> [6/5] [UU_UUU] >> [========>............] recovery = 42.6% >> (1316769920/3087007744) finish=292.2min speed=100952K/sec >> bitmap: 2/23 pages [8KB], 65536KB chunk >> >> unused devices: > > Wol, > > If you read this, this may worth a mention on wiki page. > > Ramesh > Got that :-) I'll have to think how to do that - probably a section on the use of --update to fix problems. Anyway, I've marked this email so when I work my way through stuff I'll find it :-) Cheers, Wol