C# 將 UDP Wake On Lan 數據包發送到從 VPN 連接的計算機

Question

如果我從我的 local.network 連接到 VPN，我想將 package 發送到的計算機也連接到該網絡，它對我有用，但是如果我連接到移動數據並連接到 VPN ，它不執行 WakeOnLan，不，我沒有得到任何異常或任何東西，一切運行正常，但我想通過其 MAC 傳遞的遠程計算機沒有打開。

    public static async Task WakeOn(string macAddress)
        {
            byte[] magicPacket = BuildMagicPacket(macAddress);
            foreach (NetworkInterface networkInterface in NetworkInterface.GetAllNetworkInterfaces().Where((n) =>
                n.NetworkInterfaceType != NetworkInterfaceType.Loopback && n.OperationalStatus == OperationalStatus.Up))
            {
                IPInterfaceProperties iPInterfaceProperties = networkInterface.GetIPProperties();
                foreach (MulticastIPAddressInformation multicastIPAddressInformation in iPInterfaceProperties.MulticastAddresses)
                {
                    IPAddress multicastIpAddress = multicastIPAddressInformation.Address;
                    if (multicastIpAddress.ToString().StartsWith("ff02::1%", StringComparison.OrdinalIgnoreCase)) // Ipv6: All hosts on LAN (with zone index)
                    {
                        UnicastIPAddressInformation unicastIPAddressInformation = iPInterfaceProperties.UnicastAddresses.Where((u) =>
                            u.Address.AddressFamily == AddressFamily.InterNetworkV6 && !u.Address.IsIPv6LinkLocal).FirstOrDefault();
                        if (unicastIPAddressInformation != null)
                        {
                            await SendWakeOnLan(unicastIPAddressInformation.Address, multicastIpAddress, magicPacket);
                            break;
                        }
                    }
                    else if (multicastIpAddress.ToString().Equals("224.0.0.1")) // Ipv4: All hosts on LAN
                    {
                        UnicastIPAddressInformation unicastIPAddressInformation = iPInterfaceProperties.UnicastAddresses.Where((u) =>
                            u.Address.AddressFamily == AddressFamily.InterNetwork && !iPInterfaceProperties.GetIPv4Properties().IsAutomaticPrivateAddressingActive).FirstOrDefault();
                        if (unicastIPAddressInformation != null)
                        {
                            await SendWakeOnLan(unicastIPAddressInformation.Address, multicastIpAddress, magicPacket);
                            break;
                        }
                    }
                }
            }
        }
        static byte[] BuildMagicPacket(string macAddress) // MacAddress in any standard HEX format
        {
            macAddress = Regex.Replace(macAddress, "[: -]", "");
            byte[] macBytes = new byte[6];
            for (int i = 0; i < 6; i++)
            {
                macBytes[i] = Convert.ToByte(macAddress.Substring(i * 2, 2), 16);
            }

            using (MemoryStream ms = new MemoryStream())
            {
                using (BinaryWriter bw = new BinaryWriter(ms))
                {
                    for (int i = 0; i < 6; i++)  //First 6 times 0xff
                    {
                        bw.Write((byte)0xff);
                    }
                    for (int i = 0; i < 16; i++) // then 16 times MacAddress
                    {
                        bw.Write(macBytes);
                    }
                }
                return ms.ToArray(); // 102 bytes magic packet
            }
        }
        static async Task SendWakeOnLan(IPAddress localIpAddress, IPAddress multicastIpAddress, byte[] magicPacket)
        {
            using (UdpClient client = new UdpClient(new IPEndPoint(localIpAddress, 0)))
            {
                await client.SendAsync(magicPacket, magicPacket.Length, multicastIpAddress.ToString(), 9);
            }
        }

Answer 1

UDP 使用廣播，廣播不會轉發到.network 之外，您可能需要添加例外。 UDP 是無連接的，當你想從 seperate.networks 與 UDP 通話時，你會發現這很困難。

這是更多信息：

https://techhub.hpe.com/eginfolib.networking/docs/switches/WB/15-18/5998-8166_wb_2920_mrg/content/ch03s10.html