Sentinel provides scalability for data processing, including flows and streaming telemetry. It also supports thresholding for streaming telemetry if you are using OpenNMS Newts. If you are using Minions or looking for scalable flow processing, you need Sentinel.

Sentinel is a Karaf container that handles data processing for OpenNMS and Minion, spawning new containers as necessary to deal with increased data volume.

This section describes how to install the Sentinel to scale individual components.

Keep the following in mind when using Sentinel:

  • Use only for distribution of Telemetryd functionality (such as processing flows, or use the existing telemetry adapters to store measurements data to OpenNMS Newts).

  • Requires a Minion to work as a (message) producer.

  • In most cases, you should disable adapters and listeners in Horizon that are also run by a Sentinel instance.

At the moment Sentinel can distribute only flows.