From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Greaves Subject: Re: Problem creating software raid - Device or resource busy. Date: Fri, 03 Aug 2007 09:54:11 +0100 Message-ID: <46B2ED33.8040303@dgreaves.com> References: <11978339.post@talk.nabble.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <11978339.post@talk.nabble.com> Sender: linux-raid-owner@vger.kernel.org To: Basheer Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids Basheer wrote: > Hi, Hi I'm not familiar with your kernel or mdadm versions - please say. > Drive 1 > ---------- > /dev/sda1 = swap > /dev/sda2 = linux raid (os & data is here) > /dev/sda3 = linux raid Are you describing partition types here (ie 0xfd = raid autodetect in fdisk)? > Drive 2 > ---------- > /dev/sdb1 = swap > /dev/sdb2 = linux resiser > /dev/sdb3 = linux reiser Do you mean you actually have live filesystems here? You seem to indicate that there are filesystems on disk 2 but none on disk 1. Yet you say "os & data is here" ? What do you mean by that? Please show: * partitions of both disks * existing filesystems on both disks FYI A raid device is usually made from empty partitions (devices) and you create a new filesystem inside the raid device. You can't usually just 'raid' them after the fact. > Using mdadm I managed to create /dev/md0 in raid 1 (mirror). What command? > /dev/sda3 & /dev/sdb3 where added to this set. That would make sense - but a normal md device has a superblock and this would overwrite bits of your filesystem if you already have data on the disk. That is bad. > Good so far.... hmmmm.... debatable :) > now for the problem.... > > Problems Area > ----------------------- > Using mdadm I failed to create /dev/md1 in raid 1 (mirror). > /dev/sda2 & /dev/sdb2 where part of this set. > I get this error: mdadm: cannot open device /dev/sda2: Device or > resource busy. yes. It sounds like you've got some confusion about creating a mirrored filesystem. I suspect you have a mounted filesystem on /dev/sda2 Have a look at the FAQ stuff here: http://linux-raid.osdl.org/ > I booted from rescue CD, and ran the mdam command to create /dev/md1 > ... and it worked! I let the raid sync. Well, it would :) The rescue system won't have mounted anything. > How to do I solve this? I think you need to: * repair any damage to your data * prepare your kernel and init system * go to a rescue system * create a 'broken' mirror using your empty disk (disk2?). * make a filesystem on the broken mirror * copy the good filesystems to the broken mirror * add the now free partitions from disk1 to the broken mirror * wait for a resync * reboot David