操作场景

当网站报错时，某些场景下重试能够避免这类错误，此时通过配置重试策略，能够有效降低这类错误，提升用户访问网站的体验。

部署服务

部署 v1 和 v2 版本的 deployment以及对应的service 至集群

apiVersion: apps/v1
kind: Deployment
metadata:
  name: product-v2
  namespace: base
  labels:
    app: product
    version: v2
spec:
  replicas: 1
  selector:
    matchLabels:
      app: product
      version: v2
  template:
    metadata:
      labels:
        app: product
        version: v2
    spec:
      containers:
        - name: product
          image: nginx:1.25-alpine
          ports:
            - containerPort: 80
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: product-v1
  namespace: base
spec:
  replicas: 1
  selector:
    matchLabels:
      app: product
      version: v1
  template:
    metadata:
      labels:
        app: product
        version: v1
    spec:
      containers:
        - name: product
          image: nginx:1.25-alpine
          ports:
            - containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
  labels:
    app: product
  name: product
  namespace: base
spec:
  ports:
  - name: http
    port: 80
    protocol: TCP
    targetPort: 80
  selector:
    app: product
  type: ClusterIP

应用服务网格配置

通过VirtualService对服务的重试策略进行配置，控制服务的重试行为。将以下VirtualService的yaml文件部署到集群：

apiVersion: networking.istio.io/v1beta1
kind: VirtualService
metadata:
  name: product-vs
  namespace: base
spec:
  gateways:
  - mesh
  hosts:
  - product
  http:
  - route:
    - destination:
        host: product
        port:
          number: 80
    retries:
      attempts: 3
      retryOn: 5xx

部署完成后，当服务返回5xx（服务端错误）错误时，网格会自动为请求进行重试，重试次数上限的3次。