panic(err)
			}
		}
	}
}

func getHosts(n int) (hosts []string, listeners []net.Listener, err error) {
	for i := 0; i < n; i++ {
		l, err := net.Listen("tcp", "127.0.0.1:0")
		if err != nil {
			if l, err = net.Listen("tcp6", "[::1]:0"); err != nil {
				return nil, nil, fmt.Errorf("httptest: failed to listen on a port: %v", err)
			}
		}
		addr := l.Addr()

* Fix an issue where port forwarding doesn't forward local TCP6 ports to the pod ([#57457](https://github.com/kubernetes/kubernetes/pull/57457), [@vfreex](https://github.com/vfreex))

func (m MQTTArgs) Validate() error {
	if !m.Enable {
		return nil
	}
	u, err := xnet.ParseURL(m.Broker.String())
	if err != nil {
		return err
	}
	switch u.Scheme {
	case "ws", "wss", "tcp", "ssl", "tls", "tcps":
	default:
		return errors.New("unknown protocol in broker address")
	}
	if m.QueueDir != "" {
		if !filepath.IsAbs(m.QueueDir) {
			return errors.New("queueDir path should be absolute")
		}

httpbin            httpbin-65975d4c6f-jr69n                             10.244.1.10 ambient-worker        None                                TCP
istio-system       istiod-8c7b98fc4-mwjfp                               10.244.2.49 ambient-worker2       None                                TCP

-N ISTIO_IN_REDIRECT
-N ISTIO_OUTPUT
-A ISTIO_INBOUND -p tcp --dport 15008 -j RETURN
-A ISTIO_REDIRECT -p tcp -j REDIRECT --to-ports 15001
-A ISTIO_IN_REDIRECT -p tcp -j REDIRECT --to-ports 15006
-A PREROUTING -p tcp -j ISTIO_INBOUND
-A ISTIO_INBOUND -p tcp --dport 15020 -j RETURN
-A ISTIO_INBOUND -p tcp --dport 15021 -j RETURN
-A ISTIO_INBOUND -p tcp --dport 15090 -j RETURN
-A ISTIO_INBOUND -p tcp -j ISTIO_IN_REDIRECT
-A OUTPUT -p tcp -j ISTIO_OUTPUT

KUBERNETES_PORT=tcp://10.110.0.1:443
# shellcheck disable=SC2034
KUBE_DNS_PORT_53_TCP_ADDR=10.110.0.10
# shellcheck disable=SC2034
KUBE_DNS_PORT=udp://10.110.0.10:53
# shellcheck disable=SC2034
KUBERNETES_SERVICE_PORT_HTTPS=443
# shellcheck disable=SC2034
KUBERNETES_PORT_443_TCP_PORT=443
# shellcheck disable=SC2034
KUBERNETES_PORT_443_TCP=tcp://10.110.0.1:443
# shellcheck disable=SC2034
KUBE_DNS_PORT_53_TCP_PORT=53

-N ISTIO_IN_REDIRECT
-N ISTIO_OUTPUT
-A ISTIO_INBOUND -p tcp --dport 15008 -j RETURN
-A ISTIO_REDIRECT -p tcp -j REDIRECT --to-ports 15001
-A ISTIO_IN_REDIRECT -p tcp -j REDIRECT --to-ports 15006
-A PREROUTING -p tcp -j ISTIO_INBOUND
-A ISTIO_INBOUND -p tcp --dport 15020 -j RETURN
-A ISTIO_INBOUND -p tcp --dport 15021 -j RETURN
-A ISTIO_INBOUND -p tcp --dport 15090 -j RETURN
-A ISTIO_INBOUND -p tcp -j ISTIO_IN_REDIRECT
-A OUTPUT -p tcp -j ISTIO_OUTPUT

-N ISTIO_IN_REDIRECT
-N ISTIO_OUTPUT
-A ISTIO_INBOUND -p tcp --dport 15008 -j RETURN
-A ISTIO_REDIRECT -p tcp -j REDIRECT --to-ports 15001
-A ISTIO_IN_REDIRECT -p tcp -j REDIRECT --to-ports 15006
-A PREROUTING -p tcp -j ISTIO_INBOUND
-A ISTIO_INBOUND -p tcp --dport 15020 -j RETURN
-A ISTIO_INBOUND -p tcp --dport 15021 -j RETURN
-A ISTIO_INBOUND -p tcp --dport 15090 -j RETURN
-A ISTIO_INBOUND -p tcp -j ISTIO_IN_REDIRECT
-A OUTPUT -p tcp -j ISTIO_OUTPUT

-N ISTIO_IN_REDIRECT
-N ISTIO_OUTPUT
-A ISTIO_INBOUND -p tcp --dport 15008 -j RETURN
-A ISTIO_REDIRECT -p tcp -j REDIRECT --to-ports 15001
-A ISTIO_IN_REDIRECT -p tcp -j REDIRECT --to-ports 15006
-A PREROUTING -p tcp -j ISTIO_INBOUND
-A ISTIO_INBOUND -p tcp --dport 22 -j RETURN
-A ISTIO_INBOUND -p tcp --dport 15020 -j RETURN
-A ISTIO_INBOUND -p tcp --dport 15021 -j RETURN
-A ISTIO_INBOUND -p tcp --dport 15090 -j RETURN

			// Enable TCP quick ACK, John Nagle says
			// "Set TCP_QUICKACK. If you find a case where that makes things worse, let me know."
			_ = syscall.SetsockoptInt(fd, syscall.IPPROTO_TCP, unix.TCP_QUICKACK, 1)

			// The time (in seconds) the connection needs to remain idle before
			// TCP starts sending keepalive probes
			_ = syscall.SetsockoptInt(fd, syscall.IPPROTO_TCP, syscall.TCP_KEEPIDLE, 15)