OpenNMS is an enterprise grade network monitoring platform developed under the Open Source model. It consists of a community supported open-source project as well as a commercial services, training and support organization.
OpenNMS aims to be a truly distributed, scalable platform for all aspects of the Fault, Configuration, Accounting, Performance, Security (FCAPS) network management model, and to make this platform available to both open source and commercial applications.
It has a configurable, event-driven messaging subsystem that allows you to plug-in event streams from other sources, such as vulnerability information from Nessus, tailed log files, and /proc-based monitors.
OpenNMS has a wide variety of monitors available.
Key Features
- Service Polling – determining service availability.
- Data Collection – collecting, storing and reporting on network information.
- Event and Notification Management – receiving events, both internal and external.
- Thresholding – evaluating polled latency data or collected performance data against configurable thresholds, creating events when these are exceeded or rearmed.
- Alarms and automations – reducing events according to a reduction key and scripting automated actions centered around alarms.
- Notifications – sending notices regarding noteworthy events via e-mail, XMPP, or other means.
Website: www.opennms.com
Support: Discourse Group
Developer: Tarus Balog
License: GNU General Public License v2.0

OpenNMS is written in Java. Learn Java with our recommended free books and free tutorials.
Related Software
| System Monitoring Tools | |
|---|---|
| Prometheus | Systems and service monitoring system |
| Nagios | Host and service monitor designed to inform you of network problems |
| OpenNMS | Enterprise grade network monitoring platform |
| LibreNMS | Fully featured network monitoring system |
| SigNoz | Monitor your applications and troubleshoot problems |
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| Jaeger | Distributed tracing system |
| Beszel | Lightweight server monitoring platform |
| Loki | Horizontally-scalable, highly-available, multi-tenant log aggregation system |
| Cockpit | Sysadmin login session in a web browser |
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| HyperDX | Cloud-based production monitoring and debugging tool |
| NetXMS | Network and infrastructure monitoring and management system |
| FreeNATS | Automatic network status testing, alerting and reporting package |
| Cacti | Web-based frontend to RRDtool |
| Monitorix | Lightweight system monitoring tool |
| Icinga | Monitoring platform with a powerful configuration language |
| Checkmk | IT monitoring platform |
| Munin | Networked resource monitoring tool designed to be plug and play |
| Shinken | Flexible and scalable monitoring framework |
| Pandora FMS | Flexible monitoring system |
| Xymon | System for monitoring of hosts and networks |
| Mon | General-purpose problem alerting system |
Read our verdict in the software roundup.
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