Cortex Time Series Plugin

The Cortex Time Series plugin enables Horizon to persist time series performance and latency data to Cortex. The plugin uses the time series storage integration layer to convert metrics to a Prometheus model and delegate writes and reads to Cortex. The plugin also lets users visualize graphs from the Cortex instance in OpenNMS Helm through the OpenNMS performance data source or the Prometheus data source.

Cortex plugin architecture
Figure 1. Cortex Time Series plugin


Make sure you have the following before you start to use the Cortex plugin:

  • Horizon 30.0.0+ (Meridian availability with the 2023 release)

  • Cortex version 1.10.0+

We plan to keep the plugin compatible with Mimir, Grafana’s fork of Cortex, as long as Mimir remains compatible with Cortex. The minimum supported Mimir version is 2.0.0.


To use the Cortex Time Series plugin, do the following:

  1. Start Cortex.

    If your aim is to get up to speed quickly in a test environment, you can use Docker Compose to deploy a minimal, standalone Cortex cluster.

  2. Download the plugin’s .kar file from GitHub (

  3. Copy the file into ${OPENNMS_HOME}/deploy.

  4. Enable and configure time series storage plugins in Horizon:

    echo "org.opennms.timeseries.strategy=integration
    org.opennms.timeseries.tin.metatags.tag.label=${resource:label}" >> ${OPENNMS_HOME}/etc/
  5. Configure the Cortex Time Series plugin in Horizon.

    Note that you can omit this step if you use the default settings. Substitute the correct host and port for your Cortex cluster in each place where cortex-service-host:9009 appears below.

    config:edit org.opennms.plugins.tss.cortex
    property-set writeUrl http://cortex-service-host:9009/api/prom/push
    property-set readUrl http://cortex-service-host:9009/prometheus/api/v1
    property-set maxConcurrentHttpConnections 100
    property-set writeTimeoutInMs 1000
    property-set readTimeoutInMs 1000
    property-set metricCacheSize 1000
    property-set externalTagsCacheSize 1000
    property-set bulkheadMaxWaitDurationInMs 9223372036854775807
  6. Configure the plugin to remain installed after a restart of Horizon:

    echo 'opennms-plugins-cortex-tss wait-for-kar=opennms-cortex-plugin' > "$OPENNMS_HOME/etc/featuresBoot.d/cortex.boot"

Cortex tips

View the ring


View internal metrics