Prometheus JMX Exporter container for Kubernetes

This is a Docker container intended to be run in the same pod as your Java containers, to export their metrics for Prometheus.

The default CMD copies over the required JMX Exporter files to the directory specified by the SHARED_VOLUME_PATH environment variable.

Files available

• $SHARED_VOLUME_PATH/jmx_prometheus_javaagent.jar: the JMX Exporter javaagent JAR file.
• $SHARED_VOLUME_PATH/config/*.yaml: example config files for the exporter.
  • I only bothered to copy over the example Kafka config from upstream because that's what I was using.

Using this as a Kubernetes Init Container

This container is best used as an Init Container.

Add this to initContainers of your Deployment or StatefulSet:

spec:
  initContainers:
  - name: prometheus-jmx-exporter
    image: spdigital/prometheus-jmx-exporter-kubernetes:0.3.1
    env:
    - name: SHARED_VOLUME_PATH
      value: /shared-volume
    volumeMounts:
    - mountPath: /shared-volume
      name: shared-volume

The init container and your Kafka container will share a volume:

volumes:
- name: shared-volume
  emptyDir: {}

In your Kafka container, set KAFKA_OPTS to refer to files placed by the prometheus-jmx-exporter container into the shared volume:

- name: KAFKA_OPTS
  value: -javaagent:/shared-volume/jmx_prometheus_javaagent.jar=19000:/shared-volume/configs/kafka-config.yaml

Don't forget to annotate your resources so Prometheus will scrape your pod's /metrics endpoint:

annotations:
  "prometheus.io/scrape": "true"
  "prometheus.io/port": "19000"