On 02/21/2013 12:47 PM, Stone wrote: > Am 21.02.2013 18:36, schrieb Phil Turmel: >> But it does give you the locations of the backup superblocks. Use these >> numbers, starting with 32768, as "xxxx" in: >> >> fsck.ext4 -n -b xxxx /dev >> >> Once you give it a superblock that hasn't been corrupted, it should be >> able to check the rest of the filesystem. There will be damage near the >> beginning, and probably more damage where you had to put zeros. >> >> If it looks like that, do it again without "-n" to actually fix it. >> >> Phil >> > ok. i think i dont understand you not complete. > i restore now the superblock with --> fsck.ext4 -bv 4096000 > /dev/mapper/md2_nas No! You must keep using "-n" until you have seen a mostly-clean report! We don't know yet that the chunk size is right. Leaving off "-n" will simultaneously fix the superblock (and all other backup copies) and continue to fix the rest of the filesystem. You mustn't do that with a wrong chunk size--it will damage much more. > when this is done i make full filesystemcheck --> fsck.ext4 /dev/md2_nas > and answer the quest questions. > right? No. Just do the "fsck -n -b xxxx" combinations until you find a good superblock. That report will also show if there are many other errors. Expect scattered damage in the region < 384MB due to the wrong data offset. After that, there should only be errors where the new zeros are, and maybe a few scattered errors from the original crash. If there many more errors, you have the wrong chunk size. Phil -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
