The size of my MB database is meanwhile ~13 GB of storage which not only means the need for sufficient external backup storage (what I have, a 2 TB USB connected HDD) but also takes a long time to do in spite of the RPi4B power and the USB3 connection - during which the data loggin services are suspended (even though in principle data could be written to the Sqlite WAL (Write ahead logging) file and then retroactively written to the database after the backup is completed - but this doesn't happen.
- One more thing to think about ....On the MB VM the backups are created locally as compressed archives. Which saves a lot of storage space.
I suggest to offer, at least for RPi installations, a backup script option which compresses the database locally and then moves it to the external storage.
I am aware that sufficient local data storage is a prerequisite for that, but that's for the user to manage.