I use git-annex to manage all my data on all my drives. It automatically keeps track of which files are on which drives, it ensures that there are enough copies and it checksums everything. It works perfectly with offline drives.
git-annex can be a bit hard to grasp, so I suggest to create a throw-away repository, following the walkthrough[1] and try things out. See also workflows[2].
git-annex can be a bit hard to grasp, so I suggest to create a throw-away repository, following the walkthrough[1] and try things out. See also workflows[2].
[1] https://git-annex.branchable.com/walkthrough/
[2] https://git-annex.branchable.com/workflow/