Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).

Set up Java/JMX sample workload on Amazon EKS and Kubernetes

JMX Exporter is an official Prometheus exporter that can scrape and expose JMX mBeans as Prometheus metrics. For more information, see prometheus/jmx_exporter.

Container Insights can collect predefined Prometheus metrics from Java Virtual Machine (JVM), Java, and Tomcat (Catalina) using the JMX Exporter.

Default Prometheus scrape configuration

By default, the CloudWatch agent with Prometheus support scrapes the Java/JMX Prometheus metrics from http://CLUSTER_IP:9404/metrics on each pod in an Amazon EKS or Kubernetes cluster. This is done by role: pod discovery of Prometheus kubernetes_sd_config. 9404 is the default port allocated for JMX Exporter by Prometheus. For more information about role: pod discovery, see pod. You can configure the JMX Exporter to expose the metrics on a different port or metrics_path. If you do change the port or path, update the default jmx scrape_config in the CloudWatch agent config map. Run the following command to get the current CloudWatch agent Prometheus configuration:

kubectl describe cm prometheus-config -n amazon-cloudwatch

The fields to change are the /metrics and regex: '.*:9404$' fields, as highlighted in the following example.

job_name: 'kubernetes-jmx-pod'
sample_limit: 10000
metrics_path: /metrics
kubernetes_sd_configs:
- role: pod
relabel_configs:
- source_labels: [__address__]
  action: keep
  regex: '.*:9404$'
- action: replace
  regex: (.+)
  source_labels:

Other Prometheus scrape configuration

If you expose your application running on a set of pods with Java/JMX Prometheus exporters by a Kubernetes Service, you can also switch to use role: service discovery or role: endpoint discovery of Prometheus kubernetes_sd_config. For more information about these discovery methods, see service, endpoints, and <kubernetes_sd_config>..

More meta labels are provided by these two service discovery modes which could be useful for you to build the CloudWatch metrics dimensions. For example, you can relabel __meta_kubernetes_service_name to Service and include it into your metrics’ dimension. For more informatio about customizing your CloudWatch metrics and their dimensions, see CloudWatch agent configuration for Prometheus.

Docker image with JMX Exporter

Next, build a Docker image. The following sections provide two example Dockerfiles.

When you have built the image, load it into Amazon EKS or Kubernetes, and then run the following command to verify that Prometheus metrics are exposed by JMX_EXPORTER on port 9404. Replace $JAR_SAMPLE_TRAFFIC_POD with the running pod name and replace $JAR_SAMPLE_TRAFFIC_NAMESPACE with your application namespace.

If you are running JMX Exporter on a cluster with the Fargate launch type, you also need to set up a Fargate profile before doing the steps in this procedure. To set up the profile, enter the following command. Replace MyCluster with the name of your cluster.

eksctl create fargateprofile --cluster MyCluster \
--namespace $JAR_SAMPLE_TRAFFIC_NAMESPACE\
 --name $JAR_SAMPLE_TRAFFIC_NAMESPACE

kubectl exec $JAR_SAMPLE_TRAFFIC_POD -n $JARCAT_SAMPLE_TRAFFIC_NAMESPACE -- curl http://localhost:9404

Example: Apache Tomcat Docker image with Prometheus metrics

Apache Tomcat server exposes JMX mBeans by default. You can integrate JMX Exporter with Tomcat to expose JMX mBeans as Prometheus metrics. The following example Dockerfile shows the steps to build a testing image:

# From Tomcat 9.0 JDK8 OpenJDK 
FROM tomcat:9.0-jdk8-openjdk 

RUN mkdir -p /opt/jmx_exporter

COPY ./jmx_prometheus_javaagent-0.12.0.jar /opt/jmx_exporter
COPY ./config.yaml /opt/jmx_exporter
COPY ./setenv.sh /usr/local/tomcat/bin 
COPY your web application.war /usr/local/tomcat/webapps/

RUN chmod  o+x /usr/local/tomcat/bin/setenv.sh

ENTRYPOINT ["catalina.sh", "run"]

The following list explains the four COPY lines in this Dockerfile.

Build a Docker image with this configuration and upload it to an image repository.

Example: Java Jar Application Docker image with Prometheus metrics

The following example Dockerfile shows the steps to build a testing image:

# Alpine Linux with OpenJDK JRE
FROM openjdk:8-jre-alpine

RUN mkdir -p /opt/jmx_exporter

COPY ./jmx_prometheus_javaagent-0.12.0.jar /opt/jmx_exporter
COPY ./SampleJavaApplication-1.0-SNAPSHOT.jar /opt/jmx_exporter
COPY ./start_exporter_example.sh /opt/jmx_exporter
COPY ./config.yaml /opt/jmx_exporter

RUN chmod -R o+x /opt/jmx_exporter
RUN apk add curl

ENTRYPOINT exec /opt/jmx_exporter/start_exporter_example.sh

The following list explains the four COPY lines in this Dockerfile.

Build a Docker image with this configuration and upload it to an image repository.