hello. had a bad day yesterday: accidentally, the first 0.5% to 1% of my ext3 partition got overwritten, can't gauge it more exactly. Geography of the partition is: size ~100 GB. block size should be 4096. => deleted are averages to 500mb - 1gb still. I don't think it is relevant, but the device itself is /dev/loop0, because there is a cryptoloop layer between the device and the actual /dev/hda3, but i can initiate that layer properly anyway, so it shouldn't matter (should it?). When i try to mount: EXT3-fs error: ext3_check_descriptors: block bitmap for group 0 not in group (block (block 152615462) EXT3-fs: group descriptors corrupted. of course i tried e2fsck (v 1.27), but it said it could not see an ext3 on the partiiton and suggested to try another superblock (here: 8193). hopes surging, but bad luck, because block 8193 is also within the deleted area. My question therefore is, if there are any (backup) superblocks on an arbitrary ext3 partiiton which i could access to recover some data at least. I tried the formula (8192*n +1), but bad luck.....i assume that backup superblocks are not sprayed round the partition like that. anyway, if anybody'd have some some suggestions, i'd be most grateful. ben
On Nov 09, 2003 10:57 +0100, qad0t@altern.org wrote:> My question therefore is, if there are any (backup) superblocks on an > arbitrary ext3 partiiton which i could access to recover some data at > least. I tried the formula (8192*n +1), but bad luck.....i assume that > backup superblocks are not sprayed round the partition like that.Try 32768*n, where n = { 3^i, 5^i, 7^i}, so 3, 5, 7, 9, 25, 27, 49, ... This is the default spacing for filesystems larger than 500MB. Cheers, Andreas -- Andreas Dilger http://sourceforge.net/projects/ext2resize/ http://www-mddsp.enel.ucalgary.ca/People/adilger/