On Mon, Jan 25, 2010 at 10:46:47PM +0100, Mr. Tux wrote: > On Monday 25 January 2010 19.43:27 Josef Bacik wrote: > > > > How did you setup this array to begin with? I'm trying to reproduce this > > bug but I haven't been able to. Thanks, > > > > Hi Josef, > > Thanks for your help! > > Linux Kernel 2.6.32.2 from kernel.org (was marked as stable at that time, I > compiled it using make-kpkg with btrfs support inside the kernel -> not > modular) > > OS: Debian Lenny 5.03 > > I created the btrfs raid on a two sata-II drives like this: > > mkfs.btrfs -d raid1 -m raid 1 /dev/sda4 /dev/sdb4 > > Then I mounted the btrfs with: > > mount /dev/sda4 /mnt/ > > cat /proc/mounts and dmesg showed the raid was mounted successfully > > Then I started to copy large amount of data into the raid1 from a file > server. > With the copying process ongoing I detached the data cable from one device to > simulate hardware failure. Copying process went on as planed to the drive > still attached. > > Then I unmounted the btrfs raid like this: > > umount /mnt/ > > and I shut down the system. > > Now the goal was to boot and mount only the intact btrfs partition again as a > degraded raid. > > I followed the multiple-device-wiki of btrfs [1] > > I didn't try to remove the faulty device - I shut down the system already and > booted again without the faulty drive. So I tried this: > > mount -o degraded /dev/sda /mnt/ > > This caused a memory segfault - the system still ran, but I couldn't use the > array any more. > > So I used the next command > > btrfs-vol -r missing /mnt > > Complained it couldn't mount with only one member present. > > My assumption: Bad luck with the kernel - or did this memory segfault happen > on earlier kernel versions as well? > > [1] > http://btrfs.wiki.kernel.org/index.php/Using_Btrfs_with_Multiple_Devices#Replacing_Failed_Devices >
Hmm well I'm trying to reproduce that here and it's working fine, course I can't pull a cable on my disk since I only have one disk to test with. Would you mind sending me your dmesg after you try mount -o degraded /dev/sda1 /mnt/ so I can see whats going on. Thanks, Josef -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
