}

	return ipList, err
}

// sortIPs - sort ips based on higher octets.
// The logic to sort by last octet is implemented to
// prefer CIDRs with higher octets, this in-turn skips the
// localhost/loopback address to be not preferred as the
// first ip on the list. Subsequently this list helps us print
// a user friendly message with appropriate values.
func sortIPs(ipList []string) []string {
	if len(ipList) == 1 {

		return errors.Errorf("couldn't use \"%s\" as \"apiserver-advertise-address\", must be ipv4 or ipv6 address", cfg.AdvertiseAddress)
	}

	// kubeadm allows users to specify address=Loopback as a selector for global unicast IP address that can be found on loopback interface.
	// e.g. This is required for network setups where default routes are present, but network interfaces use only link-local addresses (e.g. as described in RFC5549).

	//    Default Gateway:                      10.0.0.254
	//    Gateway Metric:                       0
	//    InterfaceMetric:                      10
	//
	//Configuration for interface "Loopback Pseudo-Interface 1"
	//    DHCP enabled:                         No
	//    IP Address:                           127.0.0.1
	//    Subnet Prefix:                        127.0.0.0/8 (mask 255.0.0.0)

//
// Use viper to resolve the value of the environment variable.
var (
	HostIPv4LoopbackCidr = env.Register("ISTIO_OUTBOUND_IPV4_LOOPBACK_CIDR", "127.0.0.1/32",
		`IPv4 CIDR range used to identify outbound traffic on loopback interface intended for application container`)

	OwnerGroupsInclude = env.Register("ISTIO_OUTBOUND_OWNER_GROUPS", "*",
		`Comma separated list of groups whose outgoing traffic is to be redirected to Envoy.

//
// - isUnspecified: returns true if the IP address is the unspecified address.
// Either the IPv4 address "0.0.0.0" or the IPv6 address "::".
//
// - isLoopback: returns true if the IP address is the loopback address.
// Either an IPv4 address with a value of 127.x.x.x or an IPv6 address with a value of ::1.
//
// - isLinkLocalMulticast: returns true if the IP address is a link-local multicast address.

				if h, _, err := net.SplitHostPort(address); err == nil {
					address = h
				}
				// Create socket on specific vrf device.
				// To catch all kinds of special cases this filters specifically for loopback networks.
				if ip := net.ParseIP(address); ip != nil && !ip.IsLoopback() {
					_ = syscall.SetsockoptString(fd, syscall.SOL_SOCKET, syscall.SO_BINDTODEVICE, opts.Interface)
				}
			}
		})
		return nil
	}

	}

	device := fields[1]
	mtustr := fields[3]

	mtu, _, ok := dtoi(mtustr)
	if !ok {
		return nil, errors.New("invalid status file of interface: " + ifcstat)
	}
	ifc.MTU = mtu

	// Not a loopback device ("/dev/null") or packet interface (e.g. "pkt2")
	if stringslite.HasPrefix(device, netdir+"/") {
		deviceaddrf, err := open(device + "/addr")
		if err != nil {
			return nil, err
		}
		defer deviceaddrf.close()

true, "sort": 0, "value_type": "individual" }, "type": "graph", "xaxis": { "buckets": null, "mode": "time", "name": null, "show": true, "values": [] }, "yaxes": [ { "format": "short", "label": null, "logBase": 1, "max": null, "min": null, "show": true }, { "format": "short", "label": null, "logBase": 1, "max": null, "min": null, "show": false } ], "yaxis": { "align": false, "alignLevel": null } }, { "collapsed": false, "gridPos": { "h": 1, "w": 24, "x": 0, "y": 6 }, "id": 62, "panels": [], "title":...

        then:
        handle.waitForFinish()

        where:
        taskName << ['runJavaExec', 'runExecOperationsJavaExec', 'test']
    }

    /** To test attaching the debugger via a non-loopback network interface, we need to choose an IP address of such an interface. */
    private static final String nonLoopbackAddress() {
        println("Looking at network interfaces")

	ifaces, _ := net.Interfaces()

	for _, iface := range ifaces {
		if iface.Flags&net.FlagUp == 0 {
			continue // interface down
		}
		if iface.Flags&net.FlagLoopback != 0 {
			continue // loopback interface
		}
		addrs, _ := iface.Addrs()

		for _, addr := range addrs {
			var ip net.IP
			switch v := addr.(type) {
			case *net.IPNet:
				ip = v.IP
			case *net.IPAddr:
				ip = v.IP
			default: