Re: Trying to rescue data from a failed NTFS HD

[Antonio Diaz Diaz]

Hello Quentin,

kenadinka hrustic wrote:
> First of all, thank you for the wonderful work.

You are welcome. :-)

>     strange error I can't understand :
>     ddrescue: /dev/sde: Unaligned read error. Is sector size correct?

Ddrescue prints that error message when 'read' returns EINVAL, which usually 
means that the sector size is not correct for the drive being rescued. In 
your case the correct sector size seems to be 4096 bytes, which is probably 
the cause why the second invocation recovered much more data than the first 
(which had the incorrect value 512).

Note that the error rate skyrockets to GB/s before ddrescue errors out. 
Maybe the drive stops responding and eventually EINVAL is returned. In this 
case you will need to reset the drive and run ddrescue again.

> The disk was on a sata port. Last week it failed abruptly and I couldn't
> boot with the disk plugged in.
>
> I bought a SATA ->  USB adapter and managed to boot.
>
> The disk is shown as /dev/sde but I can't mount it. It only worked once,
> failed while I tried to copy. Never again.

It is best that the device or partition to be rescued is not mounted at all, 
not even read-only.

> Since I'm really confused, I tried to mount the .img file, with no success :

I hope you tried to mount it read-only.

>     2. Has ddrescue finished correctly ? I'm not even sure !

No. When ddrescue finishes correctly it prints "Finished" instead of an 
error message.

>     3. What should I do next ?
>     run ddrescue again ?

This is what I would do.

>     try to scrap some files from the .img ? (how ?)

If you try this, at least don't modify the .img file until ddrescue finishes 
(recovers all the recoverable data).

Best regards,
Antonio.