40 Free Open Source network monitoring tools

8. DreamSys Server Monitor

DreamSys Server Monitor can monitor servers over a network or the Internet. It can Connect, Receive, or Send & Receive tests on TCP connections, perform simple Ping tests, test services on remote machines, and restart services if necessary.


9. Fully Automated Nagios (FAN)

The purpose of FAN is to provide a quick and easy installation which includes the most-used tools in the Nagios community. The FAN CD-ROM is ISO-certified, it is thus very easy to install. A large number of tools are also being distributed, which makes the implementation of an efficient monitoring platform much easier.

FAN is based on CentOS. FAN includes the Nagios core monitoring application, Nagios plug-ins to monitor different equipment. It also includes Centreon, an excellent Web interface for Nagios, NagVis for advanced mapping (geographical, functional, by services). Lastly there is support for NDOUtils, which stores the Nagios data into a MySQL database and NRPE, which makes it possible to monitor Windows servers (the NRPE daemon is not provided)


10. Ganglia

Ganglia is a scalable distributed monitoring system for high-performance computing systems such as clusters and Grids. It is based on a hierarchical design targeted at federations of clusters. It leverages widely used technologies such as XML for data representation, XDR for compact, portable data transport, and RRDtool for data storage and visualization. It uses carefully engineered data structures and algorithms to achieve very low per-node overheads and high concurrency.

The implementation is robust, has been ported to an extensive set of operating systems and processor architectures, and is currently in use on thousands of clusters around the world. It has been used to link clusters across university campuses and around the world and can scale to handle clusters with 2000 nodes.


11. GoAccess

GoAccess was designed to be a fast, terminal-based log analyzer. Its core idea is to quickly analyze and view web server statistics in real time without needing to use your browser (great if you want to do a quick analysis of your access log via SSH, or if you simply love working in the terminal).

While the terminal output is the default output, it has the capability to generate a complete real-time HTML report (great for analytics, monitoring and data visualization), as well as a JSON, and CSV report. GoAccess is written in C.


  • Web analyzer
  • Real time server logfile analysis
  • Statistics
  • Monitor https
  • Monitor visitors
  • Metrics per Virtual Host


12. Graphite

Graphite is a highly scalable real-time graphing system. As a user, you write an application that collects numeric time-series data that you are interested in graphing, and send it to Graphite’s processing backend, carbon, which stores the data in Graphite’s specialized database. The data can then be visualized through graphite’s web interfaces.