A Linux daemon written in C and designed to monitor networked hosts and services
Nagios (formerly Netsaint) is an open source, freely distributed, fast, flexible and very powerful command-line/web-based utility implemented in C and designed from the ground up to be used as a for network services and hosts monitoring solution. It is capable of monitoring any Linux kernel-based OS, BSD distributions, UNIXes, Netware, and Microsoft Windows systems.
Nagios will help you to monitor all the systems on your IT infrastructure, reduce downtime for your company leading to reduced business losses, detect and repair security breaches in time before anything bad happens, get notified instantly when problems arise, detect issues before they occur, share data with stakeholders, as well as to plan and budget for IT upgrades.
Features at a glance
The software is capable of monitoring network services, including SMTP (Simple Mail Transfer Protocol), HTTP (Hypertext Transfer Protocol), POP3 (Post Office Protocol), PING, NNTP (Network News Transfer Protocol), as well as host resources, including processor load, memory and disk usage, log files, and running processes.
The software also features the ability to acknowledge problems, to schedule downtime for suppressing service and host notifications, to define network host hierarchy, and to notify contacts, via email, pager or other methods, when problems arise and are resolved. In addition, it offers support for implementing distributed and redundant monitoring servers.
Another interesting feature is the built-in and powerful plugin architecture, which allows users to extend the default functionality of the product through plugins. At the moment, thousands of plugins exist for the Nagios product and can be easily installed from within the app.
Supported operating systems
At the moment, Nagios runs successfully on a wide range of Linux kernel-based operating systems, independent of a hardware platform (32-bit and 64-bit are supported at this time). It can be easily deployed on any distribution of Linux via their main software repositories.