A pod makes any request with it's node IP address as source. So you could whitelist your cluster nodes' IP addresses, and it should work.

But my integration-protocol-api is Dockerized and running on Kubernetes cluster, so ip address is changing everyime when i restart my pod. how can i assign the Public and Static ip to my Kubernetes Pod

• There are several approaches, depending on your actual setup/needs and I'll try to give some options here:

  • Tie pod to specific node and expose that node's IP address through service. This would be something along those lines:

    # Quick deployment/pod manifest node selector (affinity is better)
    ...
    spec:
      nodeSelector:
        kubernetes.io/hostname: my-node-name
    ...
    # Service manifest 
    apiVersion: v1
    kind: Service
    metadata:
      name: svc-myservice
      labels:
        app: myapp
        tier: frontend
    spec:
      selector:
        app: myapp
        tier: frontend
      ports:
      - name: tcpserviceport
        protocol: TCP
        port: 8080
        targetPort: 80
      externalIPs:
      - 111.222.222.111

    Pod should be in same namespace, tied to that node via either node selector or affinity rules and have same labels as in selector for service to pick it up. IP address of cluster node with name my-node-name should be 111.222.222.111 in this example, and it would be accessible through port 8080 and that ip address.

  • If applicable, expose service through ingress and whitelist ingress public ip only. Depending on your namespace separation you'll reference your pod (wherever it might run) in ingress through corresponding service using either service name (in namespace scope) or FQDN such as:

    <service-name>.<namespace-name>.svc.cluster.local

  • Here is good overview of some methods to make it more illustrative from kubernetes docs: https://kubernetes.io/docs/tutorials/kubernetes-basics/expose-intro/