PNP4Nagios

PNP4Nagios is an open-source addon for Nagios that provides a performance data graphing frontend. It ingests check performance data produced by Nagios and stores it in a set of RRD databases, enabling historical graphs for hosts and services. The system is designed to complement the Nagios UI by presenting trends, capacity metrics, and peak usage in an accessible web interface.

Architecture: The backend parses perfdata and updates per-host/per-service RRD files using RRDTool. The frontend is a PHP-based web application that runs within the Nagios web server and renders graphs for selected hosts, services, or time ranges. Graphs can depict standard metrics such as CPU, memory, disk I/O, and network traffic, as well as custom metrics encoded in Nagios perfdata.

Integration and data sources: PNP4Nagios is designed to work with Nagios Core (and has been used with Icinga). It relies on Nagios being configured to export performance data; the addon reads that data and creates graphs automatically.

Installation and configuration: Install the PNP4Nagios package, place its web files in the Nagios web server document root, and configure Nagios to emit perfdata to PNP4Nagios. The system creates and updates RRD databases on the fly and exposes a web-based interface for graphing.

Usage and scope: Users can view graphs by host or service, select time ranges (e.g., 1 hour, 1 day, 1 week), and compare multiple metrics. PNP4Nagios is widely used for historical analysis and capacity planning in Nagios deployments.