GRPC-Health Probe（gRPC health checking on Kubernetes）如何区分活性探针和就绪探针

Question

server = ServerBuilder.forPort(port)
  .addService(new GrpcModuleHealthCheck())
  .addService(new GrpcModuleReadinessCheck())
  .addService(ProtoReflectionService.newInstance())
  .build.start

    livenessProbe:
      failureThreshold: 3
      exec:
        command: ["bin/grpc_health_probe", "-addr=:8801"]
      initialDelaySeconds: 240
      periodSeconds: 20
      successThreshold: 1
      timeoutSeconds: 15
    readinessProbe:
      failureThreshold: 3
      exec:
        command: ["bin/grpc_health_probe", "-addr=:8801"]
      initialDelaySeconds: 20
      periodSeconds: 20
      successThreshold: 1
      timeoutSeconds: 15

我刚刚测试并发现“GRPCModuleReadinessCheck”（我最后添加的健康类）实现在执行我的kubernetes pod时生效

kubectl exec -it <MY_POD_NAME> -- /bin/bash

bash-4.4$ ./grpc_health_probe -addr=localhost:8801
status: SERVING

Answer 1

我想知道这个probe实用程序二进制文件如何区分活跃度检查和就绪度检查？

简而言之，它不是。

Kubernetes定义了两种截然不同的检查：活动性检查程序是否仍然正常工作（即没有挂起），准备性检查程序是否愿意接受更多请求。

    livenessProbe:
      failureThreshold: 3
      exec:
        # considers both SERVING and NOT SERVING to be a success
        command: ["/bin/sh", "-c", "bin/grpc_health_probe -addr=:8801 2>&1 | grep -q SERVING"]
      initialDelaySeconds: 240
      periodSeconds: 20
      successThreshold: 1
      timeoutSeconds: 15
    readinessProbe:
      failureThreshold: 3
      exec:
        # fails on any response except SERVING
        command: ["bin/grpc_health_probe", "-addr=:8801"]
      initialDelaySeconds: 20
      periodSeconds: 20
      successThreshold: 1
      timeoutSeconds: 15