apiVersion: v1
kind: Service
metadata:
  name: tcp-echo
  labels:
    app: tcp-echo
    service: tcp-echo
spec:
  ipFamilyPolicy: SingleStack
  ipFamilies:
  - IPv4
  ports:
  - name: tcp
    port: 9000
  - name: tcp-other
    port: 9001
  # Port 9002 is omitted intentionally for testing the pass through filter chain.
  selector:
    app: tcp-echo
---

Ben Leggett <******@****.***> 1710179183 -0400

		{
			name: "empty ip address",
			ips:  []string{},
			ipv4: []string{},
			ipv6: []string{},
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			ipv4, ipv6 := IPsSplitV4V6(tt.ips)
			if ipv4 == nil {
				ipv4 = []string{}
			}
			if ipv6 == nil {
				ipv6 = []string{}
			}
			if !reflect.DeepEqual(ipv4, tt.ipv4) || !reflect.DeepEqual(ipv6, tt.ipv6) {

			continue
		}
		if ip.Is4() {
			ipv4 = append(ipv4, ip.String())
		} else if ip.Is6() {
			ipv6 = append(ipv6, ip.String())
		} else {
			log.Debugf("ignoring un-parsable IP address: %v", ip)
		}
	}
	return
}

// ParseIPsSplitToV4V6 returns two slice of ipv4 and ipv6 netip.Addr.
func ParseIPsSplitToV4V6(ips []string) (ipv4 []netip.Addr, ipv6 []netip.Addr) {
	for _, i := range ips {

	"syscall"
	_ "unsafe" // for linkname
)

// probe probes IPv4, IPv6 and IPv4-mapped IPv6 communication
// capabilities which are controlled by the IPV6_V6ONLY socket option
// and kernel configuration.
//
// Should we try to use the IPv4 socket interface if we're only
// dealing with IPv4 sockets? As long as the host system understands
// IPv4-mapped IPv6, it's okay to pass IPv4-mapped IPv6 addresses to

// IPLocalReservedPortsNamespacedKernelVersion is the kernel version in which net.ipv4.ip_local_reserved_ports was namespaced(netns).
// (ref: https://github.com/torvalds/linux/commit/122ff243f5f104194750ecbc76d5946dd1eec934)
const IPLocalReservedPortsNamespacedKernelVersion = "3.16"

// IPVSConnReuseModeMinSupportedKernelVersion is the minium kernel version supporting net.ipv4.vs.conn_reuse_mode.

// varyingly accepted by some programs due to an under-specification
// of the shapes of IPv4 addresses:
//
//   - IPv4 as a single 32-bit uint: 4660 (same as "1.2.3.4")
//   - IPv4 with octal numbers: 0300.0250.0.01 (same as "192.168.0.1")
//   - IPv4 with hex numbers: 0xc0.0xa8.0x0.0x1 (same as "192.168.0.1")
//   - IPv4 in "class-B style": 1.2.52 (same as "1.2.3.4")
//   - IPv4 in "class-A style": 1.564 (same as "1.2.3.4")

	// If external IPv4 connectivity exists, we can try dialing
	// non-node/interface local scope IPv4 addresses.
	// On Windows, Lookup APIs may not return IPv4-related
	// resource records when a node has no external IPv4
	// connectivity.
	testIPv4 = flag.Bool("ipv4", true, "assume external IPv4 connectivity exists")

	// If external IPv6 connectivity exists, we can try dialing

  // and host bits. For example an IPv4 address of 192.168.0.0/24, splits the
  // address into 24 bits for the network portion and 8 bits for the host portion.
  // To allocate 256 IPs, set this field to 8 (a /24 mask for IPv4 or a /120 for IPv6).
  // Minimum value is 4 (16 IPs).
  // This field is immutable.
  // +required
  optional int32 perNodeHostBits = 2;

  // ipv4 defines an IPv4 IP block in CIDR notation(e.g. "10.0.0.0/8").

	"runtime"
	"sync"
	_ "unsafe" // for linkname
)

// BUG(rsc,mikio): On DragonFly BSD and OpenBSD, listening on the
// "tcp" and "udp" networks does not listen for both IPv4 and IPv6
// connections. This is due to the fact that IPv4 traffic will not be
// routed to an IPv6 socket - two separate sockets are required if
// both address families are to be supported.
// See inet6(4) for details.