I want to backup backintime-data from an internet-facing, remote machine running debian 11 (src). That is the hardlinks-part from the title.
I want to back it up to a (very dumb) NAS (dest) in the internal network.
Connecting to both via ssh-keys and running the backup is a third machine running debian 10.
I'd like to use borgbackup - to stay with one solution for the all the machines (also: compression, encryption), but I'm open for other ideas.
For accessing remote data in borgbackup, use of sshfs is suggested in their docs. But sshfs can't handle hardlinks on the reading side.
Rsync should be/is able to handle hardlinks but can only handle one remote connection.
Using sshfs on the dest-part of rsync throws errors ( rsync: chown "dest/filename" failed: No such file or directory (2) and rsync: mknod "dest/filename" failed: Operation not permitted (1)). The sshfs-option -o sshfs_sync is used.
So I thought piping rsync into borgbackup via the stdin option, but -again according to borgbackup docs- this omits metadata (seemingly even group-/ownership) from the file.
I still have to play with this answer: https://unix.stackexchange.com/a/183516/134408
So, what could I do? What are my other options?
