From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adam Goryachev Subject: Re: raid device gone underneath array Date: Fri, 19 Oct 2012 11:24:37 +1100 Message-ID: <50809DC5.60106@websitemanagers.com.au> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Marcus Sorensen Cc: linux-raid List-Id: linux-raid.ids On 19/10/12 11:01, Marcus Sorensen wrote: > I've been using software raid to mirror two devices, and recently one > of the drives went AWOL. > > md1 : active raid1 sdm[0] sdc[1](F) > 12884900728 blocks super 1.2 [2/1] [U_] > bitmap: 1/96 pages [4KB], 65536KB chunk > > However, md1 froze, and in looking at the logs I saw this: > > Oct 18 17:47:48 sys kernel: md: cannot remove active disk sdc from md1 ... > Oct 18 17:47:48 sys kernel: md: cannot remove active disk sdc from md1 ... > > [root(marcus)@sanmirror3-01 ~]# mdadm --manage /dev/md1 --remove /dev/sdc > mdadm: cannot find /dev/sdc: No such file or directory > > /dev/sdc was already gone! The /sys/block was already removed, no > reference to it in /proc/scsi/scsi. So md1 was destined to sit there > forever. So I rebooted and started up the degraded array. > > Using kernel 3.6.2 from kernel.org I've also had this problem, I think the kernel notices the device is gone, and removes it before MD notices the problem and removes it from the array. I managed to resolve this without a reboot by manually creating the device in /dev/sdc1 or whatever, and then doing mdadm --manage /dev/md0 --remove /dev/sdc1 Regards, Adam -- Adam Goryachev Website Managers www.websitemanagers.com.au