},
		Subsets: []echo.SubsetConfig{
			{
				Version:     "v1",
				Annotations: map[string]string{annotation.SidecarInject.Name: "false"},
			},
		},
	}
	if t.Settings().EnableDualStack {
		config.IPFamilies = "IPv6, IPv4"
		config.IPFamilyPolicy = "RequireDualStack"
	}
	return b.WithConfig(config)
}

func (e *External) LoadValues(echos echo.Instances) {

		"Maximum number of full test dumps that are allowed to occur within a test suite.")
	flag.BoolVar(&settingsFromCommandLine.EnableDualStack, "istio.test.enableDualStack", settingsFromCommandLine.EnableDualStack,
		"Deploy Istio with Dual Stack enabled.")
	flag.StringVar(&settingsFromCommandLine.HelmRepo, "istio.test.helmRepo", settingsFromCommandLine.HelmRepo, "Helm repo to use to pull the charts.")

	CustomGRPCEchoImage string

	// MaxDumps is the maximum number of full test dumps that are allowed to occur within a test suite.
	MaxDumps uint64

	// EnableDualStack indicates the test should have dual stack enabled or not.
	EnableDualStack bool

	// Helm repo to be used for tests
	HelmRepo string

	DisableDefaultExternalServiceConnectivity bool

	PeerMetadataDiscovery bool

	n.B = match.ServiceName(echo.NamespacedName{Name: BSvc, Namespace: ns}).GetMatches(echos)
	n.C = match.ServiceName(echo.NamespacedName{Name: CSvc, Namespace: ns}).GetMatches(echos)
	if t.Settings().EnableDualStack {
		n.D = match.ServiceName(echo.NamespacedName{Name: DSvc, Namespace: ns}).GetMatches(echos)
		n.E = match.ServiceName(echo.NamespacedName{Name: ESvc, Namespace: ns}).GetMatches(echos)
	}

		"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,

		Subsets:         []echo.SubsetConfig{{}},
		IncludeExtAuthz: c.IncludeExtAuthz,
	}

	defaultConfigs = append(defaultConfigs, a, b, cSvc, headless, stateful, naked, tProxy, vmSvc)

	if t.Settings().EnableDualStack {
		dSvc := echo.Config{
			Service:         DSvc,
			ServiceAccount:  true,
			Ports:           ports.All(),
			Subsets:         []echo.SubsetConfig{{}},
			IncludeExtAuthz: c.IncludeExtAuthz,

			c.DnsLookupFamily = cluster.Cluster_V4_ONLY
		} else if networkutil.AllIPv6(cb.proxyIPAddresses) {
			// IPv6 only
			c.DnsLookupFamily = cluster.Cluster_V6_ONLY
		} else {
			// Dual Stack
			if features.EnableDualStack {
				// using Cluster_ALL to enable Happy Eyeballsfor upstream connections
				c.DnsLookupFamily = cluster.Cluster_ALL
			} else {
				// keep the original logic if Dual Stack is disable

		UseOriginalDst:   proto.BoolTrue,
		FilterChains:     filterChains,
		TrafficDirection: core.TrafficDirection_OUTBOUND,
	}
	// add extra addresses for the listener
	if features.EnableDualStack && len(actualWildcards) > 1 {
		ipTablesListener.AdditionalAddresses = util.BuildAdditionalAddresses(actualWildcards[1:], uint32(lb.push.Mesh.ProxyListenPort))

			integIstioVersion := cMinIstioVersion
			var migrationApp echo.Instances
			// if dual stack is enabled, a dual stack echo config should be added
			if !t.Settings().EnableDualStack {
				// Create a custom echo deployment in NS1 with subsets that allows us to test the
				// migration of a workload to istio (from no sidecar to sidecar).
				migrationApp = deployment.New(t).

	}{
		{
			check: check.OK(),
			from:  apps.B,
			host:  "bar.example.com",
		},
		{
			check: check.NotOK(),
			from:  apps.B,
			host:  "bar",
		},
	}
	if t.Settings().EnableDualStack {
		additionalTestCases := []struct {
			check echo.Checker
			from  echo.Instances
			host  string
		}{
			// apps.D hosts a dual-stack service,
			// apps.E hosts an ipv6 only service and