Traffic Monitoring Tools

What is Nagios?
Nagios is a network and sytem monitoring application. It monitors services and hosts that you specify, alerting you when things go bad or when things get better. Some of the many feature of Nagios include: monitoring of your entire IT infrastructure, know immediately when problems arise, spot problems before they occure, detect security breaches, share availability data with stakeholders, plan and budget for IT upgrades and reduce downtime and business losses.

Is Nagios Free?
This application is free to use.

Does Nagios Work on all Operating Systems?
Nagios is available for Linux operating systems.

What are the Typical Uses for Nagios?
Nagios is used to monitor network services such as SMTP, POP, HTTP, ICMP, NNTP etc. It is also used for monitoring host resources, contact notifications when host or service problems occur and gets resolved.