Steps to reproduce: 1. Create partition on disk (for example: 1 partition, size=half of /dev/sda disk) 2. Create filesystem on partition (ext3) 3. Mount partition and create some control data on partition 4. Unmount partition 5. Create RAID0 on disk (mdadm -C /dev/md/vol_1 -amd -e 0.9 -c 64 -l 0 -n 1 /dev/sda --force) 6. md127 and md127p1 appears in /dev as expected 7. Try to mount md127p1 and verify control data on them Expected result: md127p1 device mounted and control data not corrupted Actual result: 1. Mount command returns error: mount: special device /dev/md127p1 does not exists 2. md127p1 disappears from /dev/ 3. kernel indefinitely shows (until array will be stop): md126: p1 md126: detected capacity change from 0 to xxxxxxxxxxxxx md126: p1 md126: detected capacity change from 0 to xxxxxxxxxxxxx ... Additional Info: Reproduced on: - SLES11 SP1 - mdamd 3.2 from top of your devel-3.2 branch - kernel 2.6.38 RC2 I've attached script that I use to reproduce this issue. For native metadata run: ./raid_ready_drive native For imsm metadata just: ./raid_ready_drive Regards Krzysztof > -----Original Message----- > From: NeilBrown [mailto:neilb@xxxxxxx] > Sent: Wednesday, February 09, 2011 3:46 AM > To: Wojcik, Krzysztof > Cc: linux-raid@xxxxxxxxxxxxxxx > Subject: Re: Single-drive RAID0 > > On Tue, 8 Feb 2011 16:15:53 +0000 "Wojcik, Krzysztof" > <krzysztof.wojcik@xxxxxxxxx> wrote: > > > Neil, > > > > I try to create a single-drive RAID0 array with data preservation. > > It means I have a single disk with partitions and data on them. > > I would like to migrate this single disk to RAID0 array and then grow > it to N devices. > > Of course I expect partitions with my useful data will be mapped to > corresponding MD block devices (/dev/md126p1, /dev/md126p2 etc.). > Indeed they are but when I try to mount new block device it disappears > from /dev directory and mount is not succeeded. > > > /var/log/messages shows all the time: > > md126: p1 > > md126: detected capacity change from 0 to xxxxxxxxxxxxx > > > > It is not always reproducible but very often. > > I try this operation on 0.9 and imsm metadata. Symptoms are similar. > > > > Do you have any suggestions? How to fix this issue? > > > > Regards > > Krzysztof > > It isn't clear to me what the issue is and when I try something that > might be > what you are suggesting it works perfectly every time. > > Maybe if you could provide something more detailed and specific. > e.g. a series of steps that I can try together with all the messages > you get > (both from the kernel and from mdadm) throughout the process. > > That will probably help. > > NeilBrown
Attachment:
raid_ready_drive
Description: raid_ready_drive
