无法使用服务IP访问kafka

Question

要使用Zookeeper部署Kafka，我们使用以下yaml代码。 Kafka运行成功，我们能够通过pod IP写入和读取有关Kafka主题的数据，但无法通过服务IP写入Kafka主题。

apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: zookeeper-cluster1
  namespace: default
  labels:
    app: zookeeper-cluster1
spec:
  replicas: 1
  selector:
    matchLabels:
      app: zookeeper-cluster1
  template:
    metadata:
      labels:
        name: zookeeper-cluster1
        app: zookeeper-cluster1
    spec:
      hostname: zookeeper-cluster1
      containers:
      - name: zookeeper-cluster1
        image: wurstmeister/zookeeper:latest
        imagePullPolicy: IfNotPresent
        ports:
        - containerPort: 2181
        - containerPort: 2888
        - containerPort: 3888

---

apiVersion: v1
kind: Service
metadata:
  name: zookeeper-cluster1
  namespace: default
  labels:
    app: zookeeper-cluster1
spec:
  type: NodePort
  selector:
    app: zookeeper-cluster1
  ports:
  - name: zookeeper-cluster1
    protocol: TCP
    port: 2181
    targetPort: 2181
  - name: zookeeper-follower-cluster1
    protocol: TCP
    port: 2888
    targetPort: 2888
  - name: zookeeper-leader-cluster1
    protocol: TCP
    port: 3888
    targetPort: 3888

---

apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: kafka-cluster
  namespace: default
  labels:
    app: kafka-cluster
spec:
  replicas: 1
  selector:
    matchLabels:
      app: kafka-cluster
  template:
    metadata:
      labels:
        name: kafka-cluster
        app: kafka-cluster
    spec:
      hostname: kafka-cluster
      containers:
      - name: kafka-cluster
        image: wurstmeister/kafka:latest
        imagePullPolicy: IfNotPresent
        env:
        - name: KAFKA_ADVERTISED_LISTENERS
          value: PLAINTEXT://kafka-cluster:9092
        - name: KAFKA_ZOOKEEPER_CONNECT
          value: zookeeper-cluster1:2181
        ports:
        - containerPort: 9092

---

apiVersion: v1
kind: Service
metadata:
  name: kafka-cluster
  namespace: default
  labels:
    app: kafka-cluster
spec:
  type: NodePort
  selector:
    app: kafka-cluster
  ports:
  - name: kafka-cluster
    protocol: TCP
    port: 9092
    targetPort: 9092

请说明为什么与9092端口上的Kafka关联的服务无法正常工作。

谢谢