System Link Setup Documentation

[t1op]

The documentation left a lot of gaps in setup and usage.
I have been experimenting extensively to get this working for instances of Xemu and Xboxes.
In case it is helpful, I'm sharing the tutorial I put together on how to make it work for system link games.
(Note that in my testing using '-d' to connect multiple xboxes to the same host computer did not work. Traffic appeared to be forwarded but system link games were not visible.)
 
Tutorial to System Link from Xemu to Xemu using Windows 10/11

1. Set up local network for online connections.
   a) Open a port on router for online connections (google "port forwarding").
   b) Get the local network public IP for online connections (google "what is my ip").
   i. This will change occasionally.
2. Set up a remote host on a local networked computer.
   a) Get the IPv4 address of the computer.
   b) Install latest version of Python
   c) Install latest version of npcap
   d) Copy l2tunnel to host computer
   i. Create a folder named 'l2tunnel' (name is arbitrary)
   ii. Go to https://github.com/mborgerson/l2tunnel
   iii. Right click hub.py > Save Link As > save to 'l2tunnel' folder.
   iv. Go to Releases > download the latest l2tunnel.exe.zip. Unzip it to the 'l2tunnel' folder.
   e) Double click hub.py to start remote hosting.
   • A terminal window opens and should say Waiting for UDP packets on 0.0.0.0:1337.
   • Do not close this until done system linking. Restart it if it closes.
3. Set up UDP tunnel on client Xemu(s)
   a) Modern Wifi Networks often have multiple SSID. MAKE SURE YOUR CLIENT IS ON THE SAME ONE AS THE HOST.
   b) Launch Xemu.
   i. Go to Machine > Settings > Network.
   ii. Toggle "Enable" off if it is on.
   iii. For "Attached to" select "UDP Tunnel"
   iv. For a local network connection set "Remote Address" to the host IPv4 address + port 1337.
   * Example: 192.168.0.142:1337
   * If a local instance of Xemu fails to connect using a local IP address, try using the online setup below instead.
   v. For an online connection, set "Remote Address" to the host public IP address + open port.
   * Example: 1.2.3.4:4976.
   vi. Set Bind Address to 0.0.0.0:9999. (9999 is arbitrary. Pick any unused port.)
   vii. Toggle "Enable" on.
   * If you get a bind address error, change the port number and try again or exit and relaunch Xemu and try agian.
4. Connect a System Link Game
   a) Machine > Load Disc > Select the system link game iso.
   b) Exit and relaunch Xemu after the network settings are correct and game iso is selected.
   a) In-game enter a system link browser / game creation.
   • The client should then show up in the terminal window on the host.
5. Repeat steps 2-4 for any additional instances of Xemu.
6. Mac addresses must be unique in a network game.
   a) If a client is kicked when joining a game, this is a probable reason.
   b) Xemu generates a random one so this can happen.
   c) To generate a new one, use Xbox Eeprom Editor. https://github.com/Ernegien/XboxEepromEditor
   • If you would like Xemu to generate a new one:
     1. Delete/rename your xemu.toml
     2. Launch Xemu and check the settings to get the location.
     3. Reset your settings or restore your xemu.toml and point to the new eeprom.

Tutorial for connecting Xemu to real Xboxes on same LAN

1. Setup a local remote host and Xemu as in previous section.
2. Connect the real Xbox to a local networked computer (does not need to be the host)
   a) A real xbox needs to be connected to a computer running l2tunnel by ethernet, directly or through a hub/switch.
3. Get the MAC address of your Xbox. (google "get xbox mac address")
   • Example: 00:22:48:1B:8D:7C
4. Get the Device Name of your host computer's ethernet adapter using l2tunnel.
   a) Open a command prompt in your l2tunnel directory
   b) Run "l2tunnel.exe list"
   c) Find Device Name associated with your ethernet adapter's common name.
   • Look in:
     • Windows 11: Network & Internet Settings>Advanced network settings;
     • Windows 10: Network & Internet Settings>Change adapter options settings)
       ** Example: \Device\NPF_{025DE087-B541-49ED-9269-05D1C868B2B2}
5. Tunnel the Xbox incoming communication to the remote host
   a) Fill in this template and run this command in the terminal:
   l2tunnel.exe tunnel -s 1337
   • Example: l2tunnel.exe tunnel \Device\NPF_{025DE087-B541-49ED-9269-05D1C868B2B2} -s 00:22:48:1B:8D:7C 0.0.0.0 9999 192.168.0.142 1337
     ** Note: if running Xemu on the same computer don't use the same local port 9999 for listening to which you bound Xemu in step 3>b>vi in the preceding section.
6. You should now be able to connect your Xbox to a System Link game with Xemu.
7. To connect multiple Xboxes, repeat steps 2-5 with a separate computer for each Xbox but referencing the same remote host.

USING THIS SETUP
I hosted the virtual hub on my laptop, hosting and playing the system link game with an instance of Xemu.
4 people played on the TV using an OG xbox that was connected to the virtual hub using an ethernet connection to another laptop running l2tunnel.
4 people also connected and played using Xemu on 4 Steam Decks.
Other than tethering the Xbox to its own host laptop, this was a completely wireless setup.