Decentralized Monitoring with Nagios
You can use the plugin Nagios-NRPE to monitor your hosts and servers through your Nagios or Icinga monitoring system in a decentral way.
apt-get install nagios-nrpe-server
Please add the server IPs that can access your decentral monitoring plugin and the check plugins (commands) in this config file:
You can also adjust other settings. Default port is 5666.