Thanks again for this suggestion! Yesterday, I finally finished the setup on my Linux server: RAID1/LUKS/NILFS2
I have decided to not turn on Syncthing versioning. I trust versioning in the file system more.
Originally, I wanted to run Dropbox in parallel for a while, but that only works with EXT4, and so it had to go. I have more than 2TB of data. After testing Syncthing for ten months, I am confident that it is up for the task.
That issue, of course, also exists with NILFS. Normally I would use it if I accidentally damage a file and then need to go back. In that case, I can just estimate the time, open the snapshot, and pick it from there. I’ll see how it goes. In addition, I have a daily Restic backup.
Good things about NILFS are that it is part of the Linux kernel and that I don’t need to schedule the snapshoting. The file system regularly creates so called checkpoints, which can retroactively be turned into snapshots and mounted read-only.