Streaming telemetry with gNMI

This document describes how you can set up a lab environment for testing gNMI using a virtual HPE Juniper router running Junos 24.2 R1-S2.5. It shows how you can collect metrics for interfaces and CPU utilization collected with OpenNMS. This isn’t something I do every day, so I just preserve this here for my future self and the ones who want to get up to speed a bit quicker.

What you will learn

• Enable gNMI over gRPC with sensors on a HPE Juniper router
• Verify the gRPC connections and configuration
• Enable OpenNMS Horizon to subscribe to gRPC streams for sensor data
• Set up TLS on gRPC using a self-signed certificate authority
• Visualize the collected data in Grafana

Limitations

• Streaming telemetry can only be configured from the OpenNMS Core instance, see enhancement NMS-18064
• Metric labels for network interfaces are right now just resource id strings

Before you begin

You need the following environment to get a lab running:

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