Debugging Munin plugins 0. Restart munin-node (new plugins require munin-node to be restarted to register the plugin) # sudo /etc/init.d/munin-node restart 1. On the host where Munin runs, run munin-update as the Munin user account. This step will tell you whether munin (the server) is able to communicate with munin-node (the agent). # su -s /bin/bash munin # /usr/share/munin/munin-update --debug