I took notes when I set up my Rock Pi 4B with a 2TB M.2 SSD, Ubuntu server, Samba, and Plex (running in Docker). It was a great experience; the only unresolved problem is the serial console, which seems to be a common refrain. Other topics include setting up a custom x509 certificate for Plex, and using Borg to backup to S3. Some scripts and docker compose files included. Hopefully this will help someone else: