From Nagios Support Wiki
Nagios Exchange is the central place where you find all your Nagios addons, plugins, extensions, and more. The site is designed for the Nagios Community to share its best developments for and around Nagios.
Using Nagios Business Process Intelligence Addon
Nagios Business Process Intelligence is an advanced grouping tool that allows you to set more complex dependencies to determine groups states. Nagios BPI provides an interface to effectively view the 'real' state of the network. Rules for group states can be determined by the user, and parent-child relationships are easily identified when you need to 'drill down' on a problem. This tool can also be used in conjunction with a check plugin to allow for notifications through Nagios.
Integrating Nagios Business Process Addons With XI
This document describes how to install the community-developed Business Process Addons with Nagios XI. Business Process Addons is comprised of two addons - Business Process View and Business Impact Analysis. These addons are useful for showing the high-level status of critical business processes within an organization, and determining the impact of outages using simulated failures, by combining Nagios objects into logical groups from a business impact perspective.
Using DNX With Nagios
This document describes how to integrate the DNX (Distributed Nagios eXecutor) load-balancing addon with Nagios Core and Nagios XI. DNX helps address the problems of scalability and complexity of traditional distributed Naigos setups by using an architecture of a single central node and several worker nodes.
Integrating Nagvis With Nagios XI
NagVis is a popular network and system visualization tool used by many organizations to enhance their Nagios installations. This document takes administrators through the simple steps of integrating NagVis with Nagios XI.
Using NSCA With Nagios XI
This document describes how to enable and use the NSCA addon with Nagios XI. The NSCA addon allows remote Nagios servers and applications to send passive host and service check results to the Nagios XI server for processing.
Installing Cacti Alongside Nagios XI
This a command line tutorial on how to get Cacti up and running on the same server Nagios XI.