Sure!

Most tools would not work on a physically damaged partition, so the first
thing was to get an image of the filesystem on a good device. I used
ddrescue for that
(The # character is not a part of the command)

# ddrescue /dev/sdc1 /mnt/new/rescued out.log

it will try to get most of the data. you can also stop it and start it from
the point you left it just by using the same log file.

Once you have the image, its just about running the fsck to repair your
file system. However my superblock got damaged which made it mandatory to
use a different superblock. The real challege is to find that because its
location depends on the block size. But if you have created the file system
without any special options, the default will have the locations as these

 Primary superblock at 0, Group descriptors at 1-7
  Backup superblock at 32768, Group descriptors at 32769-32775
  Backup superblock at 98304, Group descriptors at 98305-98311
  Backup superblock at 163840, Group descriptors at 163841-163847
  Backup superblock at 229376, Group descriptors at 229377-229383
  Backup superblock at 294912, Group descriptors at 294913-294919
  Backup superblock at 819200, Group descriptors at 819201-819207
  Backup superblock at 884736, Group descriptors at 884737-884743
  Backup superblock at 1605632, Group descriptors at 1605633-1605639
  Backup superblock at 2654208, Group descriptors at 2654209-2654215
  Backup superblock at 4096000, Group descriptors at 4096001-4096007
  Backup superblock at 7962624, Group descriptors at 7962625-7962631
  Backup superblock at 11239424, Group descriptors at 11239425-11239431
  Backup superblock at 20480000, Group descriptors at 20480001-20480007
  Backup superblock at 23887872, Group descriptors at 23887873-23887879

You can get this list by typing the following command on a working file
system with same block size.

#dumpe2fs /dev/sda1 | grep superblock

once you know this, its just about telling fsck to use this alternate
superblock

#fsck.ext3  -y -b 4096000 /mnt/new/rescued

That's it.

On Sun, Jan 8, 2012 at 12:55 AM, Mohit Singh <[email protected]> wrote:

> congrats :)
>
> As you share the screen dumps at the time of stating this problem, can you
> also display at least the summary of the solution process. This will help
> others to solve their similar issues too.
>
> MS
>
>
>
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>



-- 
Debasish Ray Chawdhuri
http://www.geekyarticles.com/
[A collection of advanced articles on java]

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