This is interesting GroundWork Monitor Community Edition :: GroundWork Open Source

GroundWork Monitor Community Edition provides a essential IT monitoring solution that enables you to maintain network visibility and control.

This is a single server deployment that leverages the strengths of 15 other open source projects such as Nagios, rrdtool and nmap. It combines the results of these projects in to a system that evaluates the status, events and performance of monitored devices and presents these results in an easy to understand web application.
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