On Tue, 28 Jan 2014 23:31:42 -0500 Greg Freemyer
Stephen Berman
wrote: An external hard disk of mine became corrupted, and in an effort to save the data on it I dd'd it to another hard disk. Both disks were formatted in Yast (openSUSE 13.1) with a single ext4 partition. But after using dd, now the filesystem is gone from the second disk, though otherwise the partition table appears to be intact, and cat and grep show at least some of the data. I had run `e2fsck -b 32768 -c' on the first disk when the problem first appeared (it was unmountable), but that seemed to make things worse, so I'm reluctant to try it on the second disk, unless someone convinces me I used it wrong and tells me the right way. Or is there another way to restore the filesystem without losing the data?
Steve Berman
Most if not all of the recommendations were disk recovery tools or file carvers.
Both have their use, but your disk seems fine and file carving is a last resort.
Why is that?
The best option for your case is a scanner that understands ext4 directory/inside style metadata and uses it to pull out files with accurate names and even paths.
I've got commercial software that does that. The only open source app for that I know is ext4magic
http://software.opensuse.org/search?q=ext4magic
I packaged it, but I only did minimal testing. I don't know why someone else packaged the older version, but you can try it out too.
As far as I understood from the man page, this is for recovering deleted files from an intact ext4 filesystem. But my case is the opposite: the data is there, but the filesystem is gone (or anyway unrecognizable). In any case, as far as I could tell both ext4magic and foremost (the file carving tool also recommended) work essentially on an all or nothing basis. Both the corrupted disk and the good disk that I dd'd the data to are 3TB external disks, and I don't have that much space on my other disks, so until I replace the corrupted disk I can't try to recover all the data in one go. Steve Berman -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org