flag.BindEnv(fs, constants.DualStack, "", "Enable ipv4/ipv6 redirects for dual-stack.", &cfg.DualStack)
	// Allow binding to a different var, for consistency with other components
	flag.AdditionalEnv(fs, constants.DualStack, "ISTIO_DUAL_STACK")

	flag.BindEnv(fs, constants.CaptureAllDNS, "",
		"Instead of only capturing DNS traffic to DNS server IP, capture all DNS traffic at port 53. This setting is only effective when redirect dns is enabled.",

		"PILOT_ALLOW_SIDECAR_SERVICE_INBOUND_LISTENER_MERGE",
		false,
		"If set, it allows creating inbound listeners for service ports and sidecar ingress listeners ",
	).Get()

	EnableDualStack = env.RegisterBoolVar("ISTIO_DUAL_STACK", false,
		"If true, Istio will enable the Dual Stack feature.").Get()

	EnableOptimizedServicePush = env.RegisterBoolVar("ISTIO_ENABLE_OPTIMIZED_SERVICE_PUSH", true,

	if cfg.EnableCNI {
		args.AppendSet("components.cni.enabled", "true")
	}

	if ctx.Settings().EnableDualStack {
		args.AppendSet("values.pilot.env.ISTIO_DUAL_STACK", "true")
		args.AppendSet("meshConfig.defaultConfig.proxyMetadata.ISTIO_DUAL_STACK", "true")
		args.AppendSet("values.gateways.istio-ingressgateway.ipFamilyPolicy", "RequireDualStack")

	pod, ns := buildFakePodAndNSForClient()
	pod.ObjectMeta.Annotations[sidecarStatusKey] = "true"
	pod.Spec.Containers = []corev1.Container{
		{
			Name: "istio-proxy",
			Env:  []corev1.EnvVar{{Name: "ISTIO_DUAL_STACK", Value: "true"}},
		}, {Name: "mockContainer"},
	}

	mockIntercept := testDoAddRun(t, buildMockConf(true, ""), testNSName, pod, ns)

	if len(mockIntercept.lastRedirect) == 0 {