Nagios

Nagios is an open-source monitoring system for IT infrastructure, including servers, network devices, and applications. It provides comprehensive monitoring, alerting, visualization tools, and reporting capabilities. Extensible via plugins, Nagios can monitor nearly any system. Core components include Nagios Core for scheduling checks and alerts, NRPE for remote monitoring, and Nagios XI for advanced features and a user-friendly interface. Key use cases are server, network, application, and environmental monitoring, promoting uptime, resource optimization, and cost efficiency. Supported by a large community and commercial options, Nagios helps ensure system reliability and performance.

Nagios website