If you’ve ever wanted to get a script to run on boot (or have a daemon like cijoe or ar_sendmail start up, for example), you’ll need to put an appropriate script in the /etc/init.d directory. You’ll also need to ensure it is executable (chmod +x).
After that, though, you need to create appropriate symlinked versions in the run-level directories (those are the directories like /etc/rc0.d, /etc/rc1.d, etc.). The way to go about doing this is (in the most basic and default fashion):
update-rc.d <SCRIPT_NAME_FROM_INIT.D> defaults
E.g.
update-rc.d cijoed defaults
Your script should now run on boot.