s := New()
		lis, _ := net.Listen("tcp", ":0")
		port := lis.Addr().(*net.TCPAddr).Port
		grpcServer := grpc.NewServer()
		defer grpcServer.Stop()
		grpchealth.RegisterHealthServer(grpcServer, &errorNotServeServerMock{})
		go func() {
			_ = grpcServer.Serve(lis)
		}()
		// take some time to wait server boot
		time.Sleep(2 * time.Second)

		GRPCServer:      grpc.NewServer(opts...),
		faultInjectLock: &sync.Mutex{},
	}
	// Register CA service at gRPC server.
	pb.RegisterIstioCertificateServiceServer(server.GRPCServer, server)
	ghc.RegisterHealthServer(server.GRPCServer, server)
	return server, server.start(port)
}

func (s *CAServer) start(port int) error {
	listener, err := net.Listen("tcp", fmt.Sprintf("127.0.0.1:%d", port))
	if err != nil {

	} else {
		epLog.Infof("Listening GRPC on %v", p)
	}
	s.server = s.newServer(opts...)

	// add the standard grpc health check
	healthServer := health.NewServer()
	grpcHealth.RegisterHealthServer(s.server, healthServer)

	proto.RegisterEchoTestServiceServer(s.server, &EchoGrpcHandler{
		Config:    s.Config,
		Forwarder: s.f,
	})
	reflection.Register(s.server)

	healthServer.SetServingStatus("unknown-svc", grpcHealth.HealthCheckResponse_UNKNOWN)
	healthServer.SetServingStatus("not-serving-svc", grpcHealth.HealthCheckResponse_NOT_SERVING)
	grpcHealth.RegisterHealthServer(appServer, healthServer)

	listener, err := net.Listen("tcp", ":0")
	if err != nil {
		t.Errorf("failed to allocate unused port %v", err)
	}
	go appServer.Serve(listener)