func detectNodeIPs(ctx context.Context, rawNodeIPs []net.IP, bindAddress string) (v1.IPFamily, map[v1.IPFamily]net.IP) {
	logger := klog.FromContext(ctx)
	primaryFamily := v1.IPv4Protocol
	nodeIPs := map[v1.IPFamily]net.IP{
		v1.IPv4Protocol: net.IPv4(127, 0, 0, 1),
		v1.IPv6Protocol: net.IPv6loopback,
	}

	if len(rawNodeIPs) > 0 {
		if !netutils.IsIPv4(rawNodeIPs[0]) {
			primaryFamily = v1.IPv6Protocol

}

// otherFamily returns the non-selected IPFamily.  This assumes the input is
// valid.
func otherFamily(fam api.IPFamily) api.IPFamily {
	if fam == api.IPv4Protocol {
		return api.IPv6Protocol
	}
	return api.IPv4Protocol
}

var (
	_ rest.ShortNamesProvider = &REST{}
	_ rest.CategoriesProvider = &REST{}
)

		free             int
		released         string
		outOfRange       []string
		alreadyAllocated string
	}{
		{
			name:     "IPv4",
			cidr:     "192.168.1.0/24",
			family:   api.IPv4Protocol,
			free:     254,
			released: "192.168.1.5",
			outOfRange: []string{
				"192.168.0.1",   // not in 192.168.1.0/24
				"192.168.1.0",   // reserved (base address)
				"192.168.1.255", // reserved (broadcast address)

			}
		}
	}
	r.muTree.Lock()
	defer r.muTree.Unlock()
	r.tree = tree
	return nil
}

func newIPAddress(name string, svc *v1.Service) *networkingv1alpha1.IPAddress {
	family := string(v1.IPv4Protocol)
	if netutils.IsIPv6String(name) {
		family = string(v1.IPv6Protocol)
	}
	return &networkingv1alpha1.IPAddress{
		ObjectMeta: metav1.ObjectMeta{
			Name: name,
			Labels: map[string]string{

	// provide our own implementation of that interface, or else use a
	// proxy.ServiceChangeTracker to construct them and fill in the map for us.

	sct := proxy.NewServiceChangeTracker(nil, v1.IPv4Protocol, nil, nil)
	svc := &v1.Service{
		ObjectMeta: metav1.ObjectMeta{
			Name:      "cleanup-test",
			Namespace: "test",
		},
		Spec: v1.ServiceSpec{
			ClusterIP:   testClusterIP,

				s.Spec.IPFamilies = []core.IPFamily{core.IPv4Protocol, core.IPv6Protocol}
			},
			numErrs: 0,
		},

		{
			name: "invalid, service with 2+ ipFamilies",
			tweakSvc: func(s *core.Service) {
				s.Spec.IPFamilyPolicy = &requireDualStack
				s.Spec.IPFamilies = []core.IPFamily{core.IPv4Protocol, core.IPv6Protocol, core.IPv4Protocol}
			},
			numErrs: 1,
		}, {

	initOnly bool,
) (proxy.Provider, error) {
	// Create an ipv4 instance of the single-stack proxier
	ipv4Proxier, err := NewProxier(ctx, v1.IPv4Protocol,
		syncPeriod, minSyncPeriod, masqueradeAll, masqueradeBit,
		localDetectors[v1.IPv4Protocol], hostname, nodeIPs[v1.IPv4Protocol],
		recorder, healthzServer, nodePortAddresses, initOnly)
	if err != nil {
		return nil, fmt.Errorf("unable to create ipv4 proxier: %v", err)
	}

}

// AddressType represents the type of address referred to by an endpoint.
type AddressType string

const (
	// AddressTypeIPv4 represents an IPv4 Address.
	AddressTypeIPv4 = AddressType(api.IPv4Protocol)
	// AddressTypeIPv6 represents an IPv6 Address.
	AddressTypeIPv6 = AddressType(api.IPv6Protocol)
	// AddressTypeFQDN represents a FQDN.
	AddressTypeFQDN = AddressType("FQDN")
)

	}

	// TODO: use the utils/net function once is available
	size := hostsPerNetwork(cidr)
	var family api.IPFamily
	if netutils.IsIPv6CIDR(cidr) {
		family = api.IPv6Protocol
	} else {
		family = api.IPv4Protocol
	}
	// Caching the first, offset and last addresses allows to optimize
	// the search loops by using the netip.Addr iterator instead
	// of having to do conversions with IP addresses.

var oldTriggerTimeString = triggerTime.Add(-time.Hour).Format(time.RFC3339Nano)

var ipv4only = []v1.IPFamily{v1.IPv4Protocol}
var ipv6only = []v1.IPFamily{v1.IPv6Protocol}
var ipv4ipv6 = []v1.IPFamily{v1.IPv4Protocol, v1.IPv6Protocol}
var ipv6ipv4 = []v1.IPFamily{v1.IPv6Protocol, v1.IPv4Protocol}

func testPod(namespace string, id int, nPorts int, isReady bool, ipFamilies []v1.IPFamily) *v1.Pod {
	p := &v1.Pod{