Observium vs OpenNMS Horizon
A side-by-side comparison of two self-hosted monitoring & status options — licensing, setup difficulty, resource needs, and what each one replaces.
| Feature | Observium | OpenNMS Horizon |
|---|---|---|
| Deploy effort | Read-the-docs project | Under-an-hour setup |
| Health score | 0 · At risk | 83 · Excellent |
| Category | Monitoring & Status | Monitoring & Status |
| License | GPL-3.0 | AGPL-3.0 |
| Language | Shell | Java |
| Setup difficulty | Medium | Hard |
| Min. RAM | 1,024 MB | 4,096 MB |
| Deployment | bare-metal, source | docker, bare-metal |
| GitHub stars | ★ 1 | ★ 1,173 |
| First released | 2010 | 2000 |
| Replaces | SolarWinds, PRTG | SolarWinds, PRTG |
What are Observium and OpenNMS Horizon?
Observium
Observium is a network monitoring platform that auto-discovers devices via SNMP and collects performance and health data. It focuses on a clean interface and low-maintenance operation for network infrastructure.
- SNMP auto-discovery
- Network device dashboards
- Low maintenance design
- Historical performance graphs
OpenNMS Horizon
OpenNMS Horizon is an enterprise-grade network monitoring and management platform that handles fault, performance, and traffic monitoring at scale. It supports SNMP, flow analysis, and event correlation.
- Fault and performance monitoring
- Flow analysis
- Event correlation
- Scales to large networks
Observium vs OpenNMS Horizon: key differences
Observium is written in Shell, while OpenNMS Horizon is built with Java. Licensing differs — GPL-3.0 for Observium versus AGPL-3.0 for OpenNMS Horizon. Observium is the lighter option, starting around 1,024 MB of RAM against 4,096 MB for OpenNMS Horizon. OpenNMS Horizon is the more established project (first released 2000), while Observium arrived in 2010. OpenNMS Horizon has the considerably larger community, at 1,173 GitHub stars versus 1. OpenNMS Horizon lists first-class Docker deployment; Observium does not.
Why pick each one
Choose Observium if…
- Discovers devices automatically
- Clean interface
Watch out for
- Community edition lags the paid version
- SNMP-centric
Choose OpenNMS Horizon if…
- Released under the AGPL-3.0 license
- First-class Docker support for quick deployment
- Active community (1.2k GitHub stars)
- Written in Java
Frequently asked questions
Is Observium or OpenNMS Horizon better?
Neither is universally better. OpenNMS Horizon has the larger community, while Observium is simpler to set up (medium difficulty). Choose based on the comparison table above and your own setup.
Are Observium and OpenNMS Horizon free and open-source?
Yes. Observium is licensed under GPL-3.0 and OpenNMS Horizon under AGPL-3.0. Both can be self-hosted at no software cost.
Can I run Observium and OpenNMS Horizon with Docker?
Observium: check the project docs for container support. OpenNMS Horizon: yes.
Which is lighter on resources, Observium or OpenNMS Horizon?
Observium has the smaller minimum footprint at 1,024 MB of RAM, compared to about 4,096 MB for OpenNMS Horizon. Real-world usage depends on library size, user count, and enabled features.