title: How to run a command just after shutdown or halt in Debian?
body: <p>I'm working with an embedded computer that has a Debian on it. I already manage to run a command just before it has booted and play the "bell" to tell that is ready to work, and for example try to connect to a service.</p>
  
  <p>The problem is that I need to play the bell (or run any command/program) when the system is halted so is safe to un-plug the power. Is there any runscript that run just after halt?</p>