With Nagios, the leading open source infrastructure monitoring application, you can monitor your whole enterprise by using a distributed monitoring scheme in which local slave instances of Nagios perform monitoring tasks and report the results back to a single master. You manage all configuration, notification, and reporting from the master, while the slaves do all the work.
This design takes advantage of Nagios’s ability to utilize passive checks – that is, external applications or processes that send results back to Nagios. In a distributed configuration, these external applications are other instances of Nagios.
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