OpenNMS has had its ups and downs between versions, but has always been reliable and free monitoring. There are a lot of features that can be enabled with OpenNMS through the browser, but some will require having to open a text editor and manually creating or editing a text file. While there is a learning curve to this monitoring system if you've had experience with other monitoring systems, there is a very large support group that is always helpful.

Easy to use after configuration. Feature-rich. Supports escalations and different contact groups.

Not the easiest to configure for multiple groups supported.

I have been using OpenNMS for years now. The fact that it is Open Source and has a wide community support is a big plus for me. We use OpenNMS daily as a powerful tool to proactively monitor our network. It has the flexibility and it is customizable to fit our needs. I highly recommend this product for network engineers who want to closely monitor their equipment, regardless of the network vendor they use.

OpenNMS has substantial support for traps and notifications based on those traps. We use it with great success on our network to get instant notifications on hardware failures, critical links down, etc. OpenNMS excels in providing a comprehensive collection of network graphs (including CPU, temperature, VPN active sessions, and much more) that we can display in beautiful panels using Grafana. We also use the API extensively to add/remove devices from OpenNMS without having to manually perform the task and keeping all monitored devices in sync with all our other network tools.

I have to admin that OpenNMS has a learning curve, and it should have more configuration parameters available on the web interface.

OpenNMS is very powerful and customizable.

A lot of the configurations are difficult and need to be done by editing XML files.

Easy setup and monitoring all key area networks

Good for monitoring for server management.

Used as the core software to provide network, server, and application monitoring as an MSP.

The out of the box experience covers many scenarios and all the right integration and customization layers are well thought out.

It would be nice if it scaled horizontally a bit better especially in the areas of polling and gathering of performance monitoring data. Multi-tenancy is not strong.

I like event-translator and provisioning because i can fit opennms to our needs in communcation to our other tools

Difficult file-based configuration of some features Upgrade to new versions needs configuration by hand of files

I really like the way opennms is evolving, the possibility of customizing it and interfacing it with other solutions.

It's not easy for me to get the hang of, and it takes a lot of time and patience.

Great system once over the learning curve

vendor agnostic snmp gathering system. works good for that

initial configuration.