Chapter 4. Configuring Clustering

Set openshift.KUBE_PING as the value for the JGROUPS_PING_PROTOCOL environment variable.

JGROUPS_PING_PROTOCOL=openshift.KUBE_PING

Specify the OpenShift project name as the value for the OPENSHIFT_KUBE_PING_NAMESPACE environment variable. If you do not set this variable, the server behaves like a single-node cluster.

OPENSHIFT_KUBE_PING_NAMESPACE=PROJECT_NAME

Specify the label that is set at the service level as the value for the OPENSHIFT_KUBE_PING_LABELS environment variable. If you do not set this variable, pods outside the application but in the same namespace attempt to join.

OPENSHIFT_KUBE_PING_LABELS=app=APP_NAME

Grant authorization to the service account the pod is running under so that it can access the Kubernetes REST API. You grant this authorization using the OpenShift CLI, as follows:

oc policy add-role-to-user view system:serviceaccount:$(oc project -q):default -n $(oc project -q)

oc policy add-role-to-user view system:serviceaccount:$(oc project -q):eap-service-account -n $(oc project -q)

Ensure port 8888 is defined as a ping port on the pod container, as follows:

ports:
    - containerPort: 8888
      name: ping
      protocol: TCP

Set openshift.DNS_PING as the value for the JGROUPS_PING_PROTOCOL environment variable.

JGROUPS_PING_PROTOCOL=openshift.DNS_PING

Specify the name of the ping service for the cluster as the value for the OPENSHIFT_DNS_PING_SERVICE_NAME environment variable.

OPENSHIFT_DNS_PING_SERVICE_NAME=PING_SERVICE_NAME

Specify the port number where the ping service is exposed as the value for the OPENSHIFT_DNS_PING_SERVICE_PORT environment variable. The default value is 8888.

OPENSHIFT_DNS_PING_SERVICE_PORT=PING_PORT

Define a ping service that exposes the ping port, as in the following example:

apiVersion: v1
kind: Service
spec:
  clusterIP: None
  ports:
    - name: ping
      port: 8888
      protocol: TCP
      targetPort: 8888
  selector: deploymentConfig=datagrid-app
metadata:
  annotations:
    description: The JGroups ping port for clustering.
    service.alpha.kubernetes.io/tolerate-unready-endpoints: 'true'