I have a small OrangePi running some small services on it (some with Docker and some without Docker).
And I'd love to know how do you backup your single-board computers.
Do you just rsync the system to a storage server ?
Do you plug in a USB drive and rsync on it ?
Do you save only the important data or the whole system ?
For now my SBC is not backed-up and I'd like to get a good backup solution up and running quickly! (I don't trust SD cards to last long...)
I have access to USB drives and disks and also another big server with 20TB of storage which I can make the backup to if needed!
The fact that it's a "single board" computer, specifically, is mildly irrelevant, imo; just follow standard backup practices. The only way the type of computer really comes into question is whether or not it has adequate resources to run whatever backup solution that you choose. For my usecase, Borg works great, but choose whatever solution fits your requirements. The "simplest", and lightest solution is probably rsync, but that may leave a lot to be desired.