The Open Source Standard In Monitoring

Nagios Core is our original open-source monitoring solution, developed for and supported by hundreds of community members. Create your ideal monitoring and alerting tool with a flexible and extensible monitoring architecture.

Over 10,000 Commercial customers and countless community users trust Nagios to monitor their environment. No matter the industry, you can accomplish it all with Nagios.

Nagios Commercial Solutions

Nagios XI

Monitor your entire IT infrastructure quickly with the most powerful monitoring solution on the market.

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Nagios Log Server

Quickly and easily view, analyze, and archive logs from any source in one central location.

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Nagios Network Analyzer

See where your bandwidth is dipping or spiking with our commercial grade netflow data analysis solution.

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Nagios Fusion

Using Nagios Fusion you gain a centralized visual operational status and enables faster problem resolution over your entire network.


Nagios Core Resources

Download Nagios Core.

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Download the latest Nagios Core plugins package (50 plugins). 

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Web interfaces, themes, Windows and Linux interfaces, and mobile apps for Nagios. Change the look and style of Nagios to suit your needs.

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See additional projects that extend Nagios Core’s functionality.

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Help make Nagios better for yourself and impact the entire community. 

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What does Nagios Core do?

Hover over the icons to learn more

about Nagios Core’s capabilities.

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IT staff configure Nagios to monitor critical IT infrastructure components, including system metrics, network protocols, applications, services, and network infrastructure.

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Nagios sends alerts when critical infrastructure components fail and recover, providing administrators with notice of important events. Alerts can be delivered via email, SMS, or custom script.

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IT staff can acknowledge alerts and begin resolving outages and investigating immediately. Alerts can be escalated to different groups if alerts are not acknowledged in a timely manner.

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Reports provide a historical record of outages, events, notifications, and alert response for later review. Availability reports help ensure your SLAs are being met.

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Scheduled downtime prevents alerts during scheduled maintenance and upgrade windows.

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Trending and capacity planning graphs and reports allow you to identify necessary infrastructure upgrades before failures occur.

Nagios Add-on Products

Extend Core’s functionality with Nagios agents. You can retrieve
the code for any of these agents from our GitHub.

Nagios Cross Platform Agent

A cross-platform monitoring agent that can be installed on Windows, Linux/Unix, and Mac OS/X machines. NCPA features active and passive checks, remote management, and a local monitoring interface. 

Nagios Remote Plugin Executor

An agent that allows you to remotely execute Nagios plugins on Linux/Unix machines and  monitor remote machine metrics (disk usage, CPU load, etc.). NRPE can also communicate with Windows agent add-ons like NSClient++, so you can check metrics on remote Windows machines. 

Nagios Remote Data Processor

NRDP is a flexible data transport mechanism and processor for Nagios that uses standard port protocols (HTTP(S) and XML) and can be implemented as a replacement for NSCA. Designed with a simple and robust architecture, NRDP can be easily extended and customized to fit individual users’ needs.  

Nagios Data Output Utilities

NDOUtils is an add-on that lets you store current and historical status and event information from one or more Nagios instances on a MySQL/MariaDB database. Several community add-ons use this as one of their data sources. 

Nagios Service Check Acceptor

NSCA allows you to integrate passive alerts and checks from remote machines and applications with Nagios. This agent is useful for processing security alerts as well as deploying redundant and distributed Nagios setups.