Hazelcast Helm Chart

Note: This blog was originally published in November 2018, but has since been updated with the latest information.

Hazelcast is published in a form of Helm Chart. It means that now deploying a fully-functional Hazelcast cluster on Kubernetes is easier than ever.

Prerequisites

To use Helm Charts you need:

• Kubernetes cluster with kubectl configured
• Helm 3 tool installed

Installing Hazelcast Helm Chart

To install Hazelcast Helm Chart, run the following commands.

$ helm repo add hazelcast https://hazelcast-charts.s3.amazonaws.com/
$ helm repo update
$ helm install my-release hazelcast/hazelcast

That’s all! Your cluster Hazelcast is already deployed and running. You can check it with the following command:

$ kubectl get pods
NAME                                   READY     STATUS    RESTARTS   AGE
pod/my-release-hazelcast-0             1/1       Running   0          117s
pod/my-release-hazelcast-1             1/1       Running   0          76s
pod/my-release-hazelcast-2             1/1       Running   0          28s
pod/my-release-hazelcast-mancenter-0   1/1       Running   0          117s

NAME                             TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE
service/kubernetes               ClusterIP   10.19.240.1                   443/TCP    1d
service/my-release-hazelcast     ClusterIP   10.19.240.140                 5701/TCP   1m
service/my-release-hazelcast-mancenter   LoadBalancer   10.27.243.199   35.225.250.139   8080:31731/TCP,443:30457/TCP   117s

NAME                                              READY   AGE
statefulset.apps/my-release-hazelcast             3/3     118s
statefulset.apps/my-release-hazelcast-mancenter   1/1     118s

If you want to confirm that the Hazelcast members really formed a cluster, you check the logs of any Hazelcast Pod.

$ kubectl logs pod/my-release-hazelcast-0
...
Members {size:3, ver:3} [
        Member [10.16.1.13]:5701 - 46f5815a-a892-4091-b4d3-bb6940a80663 this
        Member [10.16.1.14]:5701 - e9244db3-f305-4377-8a81-ef4e89f6add6
        Member [10.16.1.15]:5701 - e9244db3-f305-4377-8a81-ef4e89f6add6
]
...

Note that you can add some configuration to your Hazelcast cluster. For example, if you wanted 4 Hazelcast members instead of 3, you could run:

$ helm install my-release hazelcast/hazelcast --set cluster.memberCount=4

For all parameters, please check the documentation.

Using Hazelcast Cluster

When the Hazelcast cluster is up and running, you can use it by a sample application deployed on Kubernetes. Here’s how Hazelcast Client could be configured in Java.

public ClientConfig clientConfig() {
    ClientConfig config = new ClientConfig();
    config.getNetworkConfig().getKubernetesConfig().setEnabled(true);
    return config;
}

Note that you need to include the latest Maven/Gradle dependency: “com.hazelcast:hazelcast-all“.

Using Management Center

By default, Management Center is installed together with Hazelcast cluster.  You can access it via LoadBalancer external IP.

$ kubectl get service my-release-hazelcast-mancenter
NAME                             TYPE           CLUSTER-IP      EXTERNAL-IP      PORT(S)                        AGE
my-release-hazelcast-mancenter   LoadBalancer   10.27.243.199   35.225.250.139   8080:31731/TCP,443:30457/TCP   10m

You can access Management Center by the URL specified in LoadBalancer: “http://<EXTERNAL-IP>:8080“.

Note that you can also use NodePort or Ingress to access Management Center application.

Other Hazelcast Charts

Similar to Hazelcast, you can install other charts:

• Hazelcast Enterprise (hazelcast/hazelcast-enterprise)
• Hazelcast Jet (hazelcast/hazelcast-jet)
• Hazelcast Jet Enterprise (hazelcast/hazelcast-jet-enterprise)