Re: [Bug-ddrescue] Recover a single NTFS partition off a damaged disk using ddrescue

[DePriest, Jason R.]

On 7/27/06, Ariel <> wrote:
> On Fri, 28 Jul 2006, Sanjay Rana wrote:
>
> > Is it possible to recover a single NTFS partition as a disk image onto a
> > different hard disk using ddrescue?
>
> > If so then what arguments will have to be used to do that and will it be
> > possible to retrieve the data from the disk image?
>
> > My hard disk has lots of bad sectors in other partitions and I am unable to
> > overwrite the partition table. Mirroring the entire disk is also taking a lot
> > longer as well.
>
> > I know the start and end of the partition in terms of the
> > cylinders,head,sector as reported by testdisk. Can this information be
> > useful?
>
> What you will need to do is create a partition on the good disk that
> exactly matches the size (in sectors!) of the old one. It is very
> important that the sector size matches.
>
> (Easiest way to do this, is partition the new hard disk using the same
> heads and sectors per track as the old one. You can only do this in linux,
> windows doesn't let you choose these numbers (although you might get lucky
> and they'll be the same anyway). Then create a partition with the same
> number of cylinders as the old one.)
>
> Then use ddrescue to recover to that partition.
>
> You could use a disk image, rather then a partition, but windows will not
> be able to use it, only linux. I think windows has better tools for
> recovering corrupted NTFS file systems, so I suggest a partition.
>
> Actually - you could maybe use vmware, with a disk image. It will trick
> windows into thinking it's a normal partition on a hard disk. It's a
> little complex, but probably doable.
>
> BTW: If you get anything useful from that partition, I suggest copying all
> the data off of it, to a new area. Don't keep the partition afterward,
> since it was the result of a corrupted NTFS, rather then a good format.
>
> Basically you will need double the amount of space of the bad partition.
>
> Hope this helps.
>
>         -Ariel

I suggest going with an image file instead of trying to get it on
another drive with the same physical layout.

Windows can mount raw (dd) images, but not natively.  I haven't seen a
good free or open source tool to do this (easily).

If you are knowledgeable, you can install Cygwin and then install
Autopsy and The Sleuthkit.

You won't be able to mount it, but you will be able to explore it and
extract files.

To mount raw images under Windows, I use Mount Image Pro or P2
Explorer.  Neither of them are free, but they work.

I actually had a NTFS formatted disk that was unmountable and unrecognizable.

I managed to get it to spin up long enough to run SpinRite 6 (not free
either) on it, which repaired it enough to mount it in Linux.

I created a dd-compliant raw image and was able to use The Sleuthkit
to recover my files.

Windows still would not recognize the drive directly, nor would it
mount it, but I was able to get my data any way.

I'm rambling, but I just wanted you to know that if you can get your
partition into a raw image format, there are tons of possibilities.

-Jason