Thanks for the info.
karamel4e wrote:
sorry about not providing the exact command I've used
No need to be sorry

- just remember that we don't have a camera above your PC, so we don't know what you are doing. Therefore you have to explain
everything, otherwise if we guess wrongly about what you have done, then you may get wrong advice, and then you may lose your data (unnecessarily) as a result, and/or we may get frustrated about wasting our time, when we find we have guessed wrongly. I hope that helps to explain things a little more, from the viewpoint of the readers.
karamel4e wrote:
sudo ddrescue --no-split /dev/sdb5 /media/0E9A45C49A45A8D3/image /media/0E9A45C49A45A8D3/logfile
What filesystem type is /media/0E9A45C49A45A8D3? (NTFS, ext[3|4], something else?) Some Linux NTFS implementations become slower when writing, as filesize increases, hence my question. I'm wondering if that issue is related to your your slow throughput, or whether it is as simple as just the source disk is slow at reading due to internal error recovery (which is very likely, but I wanted to check rather than assume).
karamel4e wrote:
I can provide the generated logfile also if needed.
Going to that level is probably more free support that I will offer remotely - I can only invest a limited time. However I'll remember your offer...
karamel4e wrote:
After that I ran the same but with the -R option - it is supposed to copy the partition from the end to the beginning, am I right?
Correct - although I didn't see you mention the result of this attempt. Was the reverse clone attempt any faster than the slow speed you were seeing when going forwards, at around 69GB?
karamel4e wrote:
(here I used another image and logfile, this means I have two different now).
No!! The whole point about ddrescue and similar tools, is that you run them many times, using different parameters if needed, with the
same output and log files. The point about using a common log file each time, is that subsequent runs of ddrescue only attempt to read parts which have not yet been successfully read. Think of it as "filling in the gaps" in your output file.
In your case, there may be no overlap between your "forwards" and "backwards" recovery runs, but now you need to merge the two image (output) files and two log files (or abandon one set, along with whatever data it contained - not a decision to be rushed). So unfortunately you've increased created a new challenge, in addition to your original one.
These files can be merged by someone with the necessary skills, but I'm not going to go into that now.
karamel4e wrote:
About the errors, that's something like what I had [snip]
That's interesting, thanks, although I specifically said you need to review the errors being logged
by the OS, if your previous question was asking why ddrescue wasn't "complaining" as you put it. You'll need to get Linux support elsewhere, as the location of the relevant log file typically depends on which specific Linux distro you're using, and whether it's a liveCD/DVD/USB or a hard disk installation. Personally I find that monitoring the type and timing of errors logged by the OS, helps me to understand what is happening in the ddrescue screen display that you provided.
Anyway, what your ddrescue display snapshot seems to show, is that the recovery was still making (very slow) progress since "time from last successful read: 0 s", with just 29kB of unreadable data so far, of the almost 70GB that was read by that point. I have seen stories from ddrescue users of them leaving the process for several weeks in extreme cases. Some clones are (eventually) mostly successful; some clones fail as the "problem disk" dies before the end of the process. As always, YMMV.
Since your "problem disk" is only 80GB, and the ddrescue screenshot shows 69GB read so far, then you're down to the last 10GB-ish, aren't you?
karamel4e wrote:
About specifying 'outfile', 'logfile', I have another hdd which I decided to use to copy the data there. It has 2 partitions, I'd like to use the second one. I can make an image or use the whole partition, I don't care which one, if that's what you mean by 'what I am trying to do'.
In the context of your previous question, which I was trying to answer but didn't know your chosen ddrescue command or what your objective was, then you have now explained why you need to use a mountpoint for a regular file, if you have decided to use that for your image file (outfile). That approach has advantages & disadvantages, but I've run out of time now to explain further.
Just briefly, you may want to investigate the ddrescue "-a" option (e.g. set a minimum speed of 10000 bytes/sec), to skip slow sections of the remaining unread section of the disk on the first pass, but read the warnings in the ddrescue online manual on that point. That
might help you to clone some of the remaining 10GB of disk space before the disk dies,
if there are any "fast" areas in that section.
After you've attempted to read the whole disk at least one without retries, then you can allow ddrescue to perform some extra retries, and/or use direct access etc. to see if any more sectors can be read.
Good luck! At least you seem to have almost 70GB of data recovered so far.