Nagios is capable of monitoring hosts and services in two ways: actively and passively. Passive checks are performed by external applications and is explain in this document.
Documentation - Passive Checks
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Article ID: 367
Created On: Sun, Jan 31, 2016 at 10:50 PM
Last Updated On: Wed, Feb 10, 2016 at 7:35 PM
Authored by: tlea
Online URL: https://support.nagios.com/kb/article/nagios-core-passive-checks-367.html