Nagios is the monitoring tool with multitude of features as given below −

• Nagios Core is open source, hence free to use.

• Powerful monitoring engine which can scale and manage 1000s of hosts and servers.

• Comprehensive web dashboard giving the visibility of complete network components and monitoring data.

• It has multi-tenant capabilities where multiple users have access to Nagios dashboard.

• It has extendable architecture which can easily integrate with third-party applications with multiple APIs.

• Nagios has a very active and big community with over 1 million + users across the globe.

• Fast alerting system, sends alerts to admins immediately after any issue is identified.

• Multiple plugins available to support Nagios, custom coded plugins can also be used with Nagios.

• It has good log and database system storing everything happening on the network with ease.

• Proactive Planning feature helps to know when it’s time to upgrade the infrastructure.