k8s中使用service做四层负载均衡

我们通过service访问k8s内部应用的时候数据包走向是从 客户端请求–>node节点的IP：端口–>service的ip：端口 -->pod的ip：端口

demo
创建一个k8s pod，通过service代理
cat pod_test.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx
spec:
  selector:
    matchLabels:
      run: nginx
  replicas: 2
  template:
    metadata:
      labels:
        run: nginx
    spec:
      containers:
      - name: nginx
        image: nginx
        ports:
        - containerPort: 80

创建一个service
cat service.yaml

apiVersion: v1
kind: Service
metadata:
  name: nginx
  labels:
    run: nginx
spec:
  ports:
  - port: 80
    protocol: TCP
  selector:
    run: nginx