On Sun, Aug 26, 2012 at 4:22 PM, Stefan Harwarth <[email protected]> wrote: > Hi cwillu, > > thanks for the quick reply. I didn't realize that my debian 6 was shipping > such an old btrfs/kernel package - though I should have known better :( > > Anyways I already tried to recover my files with an Ubuntu 12.04 (Kernel > 3.2) and following your recommendation, I upgraded to 3.5 and tried btrfsck, > btrfs-restore and btrfs-find-root on /dev/sdb as well as the partition > /dev/sdb1 but I only got "no btrfs filesystem" and "could not open root, > trying backup super" (for btrfs-restore). > > I haven't tried -o recovery yet, but it looks to me like there's no starting > point at all for the tools (which brings me back to the 6.4meg of NULL-bytes > at the start of the partition). > > So is there any chance on recovering FS information, from what I read in > wikipedia btrfs stores some copies of important FS metadata throughout the > partition.
-o recovery will try the various copies of the superblock; hopefully you haven't used "btrfs-select-super" at any point, as it works by overwriting those copies with the selected one (i.e., you get one shot). I believe btrfs doesn't write to the first couple mb of the partition, so the existence of gibberish or empty bytes there doesn't indicate a problem; more worrisome is that it isn't actually being detected as btrfs. Can you describe the setup (partitions in the filesystem, etc) a bit more, and possibly include a dmesg from after an attempt to mount it under 3.5? -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
