很多这样的网站都说无头服务的好处是直接检测Pod的IP地址，直接访问Pod。但是这个解释对我来说没有意义。原因是即使我们不使用无头服务，我们仍然可以直接访问Pod。
我认为下面的例子：

• 1 pod（这是客户端）
• 3 pod由StatefulSet管理

1.使用无头服务

apiVersion: v1
kind: Service
metadata:
  name: my-headless-service
spec:
  type: ClusterIP
  clusterIP: None
  selector:
    app: my-app
  ports:
    - name: http
      port: 80
      targetPort: 8080
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: my-statefulset
spec:
  serviceName: my-headless-service
  replicas: 3
  selector:
    matchLabels:
      app: my-app
  template:
    metadata:
      labels:
        app: my-app
    spec:
      containers:
        - name: my-container
          image: nginx
          ports:
            - name: http
              containerPort: 8080
---
# Client Pod
apiVersion: v1
kind: Pod
metadata:
  name: myapp-pod
  labels:
    name: myapp
spec:
  containers:
  - name: myapp
    image: willfarrell/ping
    ports:
    - containerPort: 8080

字符串
从名为myapp-pod的Pod中，我们可以访问由StatefulSet管理的每个Pod，如下所示

ping my-statefulset-0.my-headless-service
ping my-statefulset-1.my-headless-service
ping my-statefulset-2.my-headless-service

型
1.没有无头服务

apiVersion: v1
kind: Service
metadata:
  name: my-service
spec:
  type: ClusterIP
  selector:
    app: my-app
  ports:
    - name: http
      port: 80
      targetPort: 8080
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: my-statefulset
spec:
  serviceName: my-service
  replicas: 3
  selector:
    matchLabels:
      app: my-app
  template:
    metadata:
      labels:
        app: my-app
    spec:
      containers:
        - name: my-container
          image: nginx
          ports:
            - name: http
              containerPort: 8080
---
# Client Pod
apiVersion: v1
kind: Pod
metadata:
  name: myapp-pod
  labels:
    name: myapp
spec:
  containers:
  - name: myapp
    image: willfarrell/ping
    ports:
    - containerPort: 8080

型
从名为myapp-pod的Pod中，我们还可以访问由StatefulSet管理的每个Pod，如下所示

ping my-statefulset-0.my-service
ping my-statefulset-1.my-service
ping my-statefulset-2.my-service

型
这样我们就可以访问StatefulSet管理的Pod，而不需要headless service。
1（使用无头服务）和2（不使用无头服务）有什么区别吗？