How do you run the Notes server in the background but still be able to control the console?

You can use the GNU program called Screen to run the Notes server. You can then detach and re-attach to this window as needed from any telnet session. You can find it at any GNU software archive.

For Linux and Solaris, you can modify your rc3.d script to include this line:
su - notes -c "screen -d -m -S NotesServer server"

Applies to Notes Versions: 3 4 4.5 4.6 5