Dear Antonio Diaz Diaz,
First, I would like to thank you for providing ddrescue tool to the
community.
I am using version 1.27.
I am trying to rescue a 2TB external HDD, and the process is very slow due
to the large size.
The process is currently in the second, backward phase of copying.
I noticed some very slow regions of the disk, that I would like to skip.
I tried to use the -K (or --skip-siez=) option, but it seems not to work
during backward pass:
below is the terminal output of 2 commands, the first one that I
interrupted, and the second one where I added the -K option :
bloup@bloup-OptiPlex-9020:~$ sudo ddrescue -f -n -b4096 -c8KiB /dev/sdc
/dev/sda mapfile
GNU ddrescue 1.27
Press Ctrl-C to interrupt
Initial status (read from mapfile)
rescued: 1378 GB, tried: 2270 MB, bad-sector: 512000 B, bad areas: 125
Current status
ipos: *1695* GB, non-trimmed: 3757 MB, current rate: 0 B/s
opos: *1695* GB, non-scraped: 0 B, average rate: 439 kB/s
non-tried: 613186 MB, bad-sector: 512000 B, error rate: 0 B/s
rescued: 1383 GB, bad areas: 125, run time: 3h 16s
pct rescued: 69.15%, read errors: 87, remaining time: 4769d 21h
time since last successful read: 1s
Copying non-tried blocks... Pass 2 (backwards)^C
Interrupted by user
bloup@bloup-OptiPlex-9020:~$ sudo ddrescue -f -n -b4096 -c8KiB -K 4GB
/dev/sdc /dev/sda mapfile
[sudo] Mot de passe de jjb :
GNU ddrescue 1.27
Press Ctrl-C to interrupt
Initial status (read from mapfile)
rescued: 1383 GB, tried: 3758 MB, bad-sector: 512000 B, bad areas: 125
Current status
ipos: *1695* GB, non-trimmed: 3969 MB, current rate: 0 B/s
opos: *1695* GB, non-scraped: 0 B, average rate: 1327 B/s
non-tried: 612973 MB, bad-sector: 512000 B, error rate: 0 B/s
rescued: 1383 GB, bad areas: 125, run time: 19m 38s
pct rescued: 69.15%, read errors: 11, remaining time: 6939d 7h
time since last successful read: 0s
Copying non-tried blocks... Pass 2 (backwards)^C
Interrupted by user
As you can see, the ipos/opos was 1695 GB, and was still 1695 GB after
(expectedly) skipping 5GB.
I subsequently tried to skip "-K -5GB" but negative values are not
authorised.
Did I misunderstood what the -K option stands for?
Is there another way to skip a certain size during backward copy?
Thank you for your help,
Kind regards
Bruno Loup
