soldar:
I wasn’t able to visit this thread often enough in recent days, so I didn’t read all posts in full. Perhaps this is why I’m a bit confused, but I have a feeling it’s not only that.
What are you trying to achieve, exactly? Because it seems that at one time you want to clone and boot (and it fails), at other you just want to have a backup copy (possibly with compression). Which one is your goal?
You were also suggested to use ddrescue. The use of a tool of this kind is critical here, because the disk reports unstable sectors. They aren’t going to be readable and must be skipped while cloning. I do understand you may be confused by its interface and there is nothing wrong with that. Quite opposite: since your data is at risk and a mistake can be catastrophic, doubts are highly advised! Ask 20 times to be sure!
But there are people on the forum and we’ll happily clarify things and doubts. You may use a different program, but that gives a rise to two issues: whether they even deal correctly with such sectors and if you can find anybody knowing them well enough to help.
If there was no unstable sectors, the answer would be trivial:
cp /dev/old_hdd /dev/new_hdd
… and
cleanly reboot. One may issue that to ensure the entire write is complete before the reboot starts:
blockdev --flushbufs /dev/new_hdd
But, as long as the reboot is clean, it’s only moving the write to an earlier time, speeding up the shutdown process itself.