From mboxrd@z Thu Jan 1 00:00:00 1970 From: Asdo Subject: Re: Some md/mdadm bugs Date: Mon, 06 Feb 2012 18:07:38 +0100 Message-ID: <4F3008DA.8060402@shiftmail.org> References: <4F2ADF45.4040103@shiftmail.org> <20120203081717.195bfec8@notabene.brown> <4F2B1519.5010500@shiftmail.org> Mime-Version: 1.0 Content-Type: text/plain; format=flowed; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-reply-to: <4F2B1519.5010500@shiftmail.org> Sender: linux-raid-owner@vger.kernel.org To: NeilBrown Cc: linux-raid List-Id: linux-raid.ids On 02/02/12 23:58, Asdo wrote: > >>> Now it doesn't happen: >>> When I reinserted the disk, udev triggered the --incremental, to >>> reinsert the device, but mdadm refused to do anything because the old >>> slot was still occupied with a failed+detached device. I manually >>> removed the device from the raid then I ran --incremental, but mdadm >>> still refused to re-add the device to the RAID because the array was >>> running. I think that if it is a re-add, and especially if the >>> bitmap is >>> active, I can't think of a situation in which the user would *not* want >>> to do an incremental re-add even if the array is running. >> Hmmm.. that doesn't seem right. What version of mdadm are you running? > > 3.1.4 > >> Maybe a newer one would get this right. > I need to try... > I think I need that. Hi Neil, Still some problems on mdadm 3.2.2 (from Ubuntu Precise) apparently: Problem #1: # mdadm -If /dev/sda4 mdadm: incremental removal requires a kernel device name, not a file: /dev/sda4 however this works: # mdadm -If sda4 mdadm: set sda4 faulty in md3 mdadm: hot removed sda4 from md3 Is this by design? Would your udev rule ACTION=="remove", RUN+="/sbin/mdadm -If $name" trigger the first or the second kind of invocation? Problem #2: by reinserting sda, it became sdax, and the array is still running like this: md3 : active raid1 sdb4[2] 10485688 blocks super 1.0 [2/1] [_U] bitmap: 0/160 pages [0KB], 32KB chunk please note the bitmap is active so now I'm trying auto hot-add: # mdadm -I /dev/sdax4 mdadm: not adding /dev/sdax4 to active array (without --run) /dev/md3 still the old problem I mentioned with 3.1.4. Trying more ways: (even with the "--run" which is suggested) # mdadm --run -I /dev/sdax4 mdadm: -I would set mdadm mode to "incremental", but it is already set to "misc". # mdadm -I --run /dev/sdax4 mdadm: failed to add /dev/sdax4 to /dev/md3: Invalid argument. # mdadm -I --run sdax4 mdadm: stat failed for sdax4: No such file or directory. # mdadm -I sdax4 mdadm: stat failed for sdax4: No such file or directory. This feature not working is a problem because if one extracts one disk by mistake, and then reinserts it, even with bitmaps active, he needs to do a lot of manual work to re-add it to the arrays (potentially even error-prone, if he mistakes the partition numbers)... Thank you A.