Excerpts from Gregory L Shomo's message of 2011-04-20 08:56:02 -0400: > Chris Mason <chris.mason@xxxxxxxxxx> writes: > > > Excerpts from Gregory L Shomo's message of 2011-04-19 15:08:13 -0400: > >> Hello list- > >> > >> Under heavy load (i/o), one of our fileservers lost two drives > >> in a raid6 configuration. After the drives were synchronized, > >> we can no longer mount the multiple-device btrfs filesystem > >> due to (at least) parent transid verification. > >> > >> btrfsck built from git commit 1b444cd2e6ab8dcafdd47dbaeaae369dd1517c17 > >> runs for a while and then aborts on 'failed to find block number'. > >> Sample output includes : > > > > Looks like the rebuild gave you older copies of some of the blocks. > > btrfsck will exit out pretty early when it sees problems, but I'd say > > most of your FS is there. > > > > Can you please do a btrfs-debug-tree /dev/xxx > out, I'd like to see how > > far we get. > > > > What errors do you get when trying to mount the FS? > > > > -chris > > I'm not sure how far we will get, but btrfs-debug-tree > has been running for over 12h now and the screenlog is > at 80Gb. This may not be surprising, as the filesystem > is large (60T) and has millions of files. > > From the logs at boottime, we have > > btrfs: failed to read the system array on sdd1 > btrfs: open_ctree failed > > Should we wait for the btrfs-debug-tree to finish > before executing an other mount command ? For btrfs-debug-tree to run this long, big parts of your FS must be valid. Also, btrfs-debug-tree must have been able to read the sys array (which mount was complaining about). How easily can you try a newer kernel? We need to make sure and do readonly operations (mount -o ro), but we may be able to pull out a bunch of files. -chris -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
