My golden rule - if you change something somewhere on a critical box, reboot the box and see if it resume working operation. (Some critical changes/fixes cannot be done remotely, and require you to be present physically).
If it does not, fix it before somebody complain.
If you want to be a real bastard, do some changes to a running config on a router, delete the saved config, and walk away. Chances are it'll be rebooted, losing all of its configuration. Muhuhaha.