Replying to @⁨lch361@discuss.tchncs.de⁩

This is the correct solution for unattended file copy/sync, plug the external drive and wait till the copy finishes. The only difficulty is monitoring progress/completion/failure if that’s on a headless machine. I built a basic orchestration system with systemd .path/.mount/.timer/.service units, logging and monitoring around this, once you understand your exact needs and get it working, it works.