// UnbindAddress unbind address from the interface
	UnbindAddress(address, devName string) error
	// EnsureDummyDevice checks if dummy device is exist and, if not, create one.  If the dummy device is already exist, return true.
	EnsureDummyDevice(devName string) (exist bool, err error)
	// DeleteDummyDevice deletes the given dummy device by name.
	DeleteDummyDevice(devName string) error

		}
	}
	// return error message if address is not found in slice h.localAddresses[devName]
	return fmt.Errorf("address: %s is not found in interface: %s", address, devName)
}

// EnsureDummyDevice is a mock implementation
func (h *FakeNetlinkHandle) EnsureDummyDevice(devName string) (bool, error) {
	if len(devName) == 0 {
		return false, fmt.Errorf("device name can't be empty")
	}
	if _, ok := h.localAddresses[devName]; !ok {

		if err != unix.ENXIO {
			return fmt.Errorf("error unbind address: %s from interface: %s, err: %v", address, devName, err)
		}
	}
	return nil
}

// EnsureDummyDevice is part of interface
func (h *netlinkHandle) EnsureDummyDevice(devName string) (bool, error) {
	_, err := h.LinkByName(devName)
	if err == nil {
		// found dummy device
		return true, nil
	}
	dummy := &netlink.Dummy{

	proxier.natChains.Write("*nat")

	proxier.createAndLinkKubeChain()

	// make sure dummy interface exists in the system where ipvs Proxier will bind service address on it
	_, err := proxier.netlinkHandle.EnsureDummyDevice(defaultDummyDevice)
	if err != nil {
		proxier.logger.Error(err, "Failed to create dummy interface", "interface", defaultDummyDevice)
		return
	}

	// make sure ip sets exists in the system.

		ipt := iptablestest.NewFake()
		ipvs := ipvstest.NewFake()
		ipset := ipsettest.NewFake(testIPSetVersion)
		proxier := NewFakeProxier(ctx, ipt, ipvs, ipset, nil, nil, v1.IPv4Protocol)

		proxier.netlinkHandle.EnsureDummyDevice(defaultDummyDevice)
		if testCases[i].oldVirtualServer != nil {
			if err := proxier.ipvs.AddVirtualServer(testCases[i].oldVirtualServer); err != nil {