Free, powerful monitoring and alerting for servers, networks, applications and services.
Monitor Windows, Linux, networks, and services to prevent downtime before it impacts critical business processes.
Extend capabilities with thousands of plugins and add-ons including NRPE, NSCA, and custom monitoring solutions.
Free, community-supported platform with intuitive wizards and dashboards backed by 25+ years of monitoring expertise.
Already using Nagios Core? Upgrade to CSP to unlock enterprise features while keeping it free!
Production-ready monitoring trusted by thousands of organizations worldwide.
The monitoring engine that started it all. Monitor websites, servers, switches, routers, firewalls, ports, applications, metrics, and more.
Monitor Windows, Linux, and Mac in real time. NCPA is a cross-platform agent for servers, system metrics, applications, and networks.
50+ ready-made checks packaged with Nagios including check_ping, check_ssh, check_cpu, check_memory, check_linux, and more.
Adds scalability and performance to Nagios Core, enabling users of Nagios Core and XI to effectively monitor large environments.
Web UIs, auto-discovery scripts & change management interfaces to simplify Nagios configuration without manual file editing.
Transform Nagios data into dashboards, network maps & performance graphs for intuitive monitoring and business insights.
Want everything in one comprehensive package? Get all essential Nagios open-source projects plus a pre-configured Nagios XI VM in one unified download.
Join thousands of users, developers, and contributors who make Nagios the world’s most trusted monitoring solution.
Nagios Core is supported by a global community of users, developers, and contributors. They extend its capabilities every day, helping monitor everything from simple setups to complex infrastructure.
Nagios was designed from the start to be open and flexible. That community-driven foundation is what makes it powerful–and why it’s been trusted for over two decades.
Nagios Exchange is home to thousands of community-built plugins, scripts, and add-ons. From servers and networks to applications and services, it makes extending Core easy and accessible.
Browse thousands of community plugins.
Get help from other Nagios users.
Search guides, docs, and resourcs.
Professional training and certification programs.
References for plugin developers.
Online manuals for Nagios projects.
6 min read
A comparison of features, capabilities, and use cases to help you choose between Nagios Core and Nagios XI for your monitoring needs.
5 min read
Step-by-step guide for upgrading from Nagios Core to Nagios XI, including planning considerations and migration best practices.
20 min read
Watch this webinar to discover the key advantages of upgrading from Nagios Core to XI, including enhanced features and improved usability.
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