I'm looking for something like diff for filesystems, but a tricky option

Question

Backup

There is a 200GB HDD. It has files on it. I correct them. (10-20GB changes per week)

There are 2-3 more copies of this hard drive, located in places where there is no Internet (or it is very bad), but where I appear from time to time. Copies are never self-edited.

I do not want to carry the original screw with me. I want to carry the difference on a flash drive. I would not like to keep another 200GB of data next to the original for comparison and diff generation.

Any ideas how I can get out?

OS: Linux

Answer 1

put in git and do a git diff to create a patch between edits

Answer 2

Can try to collect changed files by modification date?
Or use some version control system (make a commit after the backup)... The second option looks more interesting, but I don't know how to implement it :-)

Answer 3

bsdiff? Only it seems to eat a lot of memory and is not very suitable for entire file systems ...

Answer 4

If you just think logically, then you either need to store a history of changes for a fairly long period of time (“from time to time, I appear”), i.e. diffs after each edit, or store a separate snapshot for each visited place.
I don’t think it will “take off”, and the first and second are rather time-consuming with the indicated amount of data / edits, especially in “home” conditions.