* [NetXMS](https://www.netxms.org/) - Open Source network and infrastructure monitoring and management. ([Source Code](https://github.com/netxms/netxms))
* [Observium](http://www.observium.org/) - SNMP monitoring for servers and networking devices. Runs on linux.
* [OMD](http://omdistro.org/) - The Open Monitoring Distribution.
* [Performance Co-Pilot](http://pcp.io) - Lightweight, distributed system performance and analysis framework.