Re: [Bug-ddrescue] ddrescue 1.2 crashes without writing mapfile

[Antonio Diaz Diaz]

Hello Bill,

First of all, ddrescue 1.2 is ancient (2006). I guess you mean 1.21, or 
1.20.

bill evergreen wrote:
> I am trying to image a harddisk with defect sectors. When the system tries
> to read the bad sectors, the following happend: Either:
>
> -  the whole machine crashes (Kernel: 3.5.0-30-generic). Removing the power
> is required, in order to reboot.

If the whole machine crashes, then the problem is in the hardware or in 
the kernel.


> -  ddrescue crashes and dismounts the harddisk

Ddrescue does not "dismount" devices. Maybe you mean the hard disk 
disappears from /dev?

Does ddrescue show any error message?


> I use the command #ddrescue -v -n /dev/sdc
> /media/root/recovered/20160321.dd ddmapfile.txt
>
> Why no mappfile.txt is written to the target device (
> /media/root/recovered/)

Because you told ddrescue to write the mapfile in the current directory. 
The correct command would be:

ddrescue -v -n /dev/sdc /media/root/recovered/20160321.dd 
/media/root/recovered/ddmapfile.txt


> Is there a way to add the remaining part of the disk (after a reboot) to
> the already existing recovered/20160321.dd  (e.g. with "ddrescue -v -R -n
> and ddrescue -v -R -r1") ?

Ddrescue always adds the remaining part of the disk to the existing 
/media/root/recovered/20160321.dd. No need to change the command for that.
http://www.gnu.org/software/ddrescue/manual/ddrescue_manual.html#Introduction


Regards,
Antonio.