The Multiplayer tab lists multiplayer games that you can join. Servers on the local network are discovered automatically and are visible immediately in the Multiplayer games list. The dengine.net master server is also automatically queried for any public servers.
Viewing server information. Right-click a server in the list to view status information about it. The same popup can be opened by clicking the small “…” button in the server description. The status information includes:
Joining a game. Join an open multiplayer game by clicking “Join” either in the server list or in the server information popup.
Player name and color. When a game is running (after joining a multiplayer game or also in single-player), go to the game's “Options” menu and select “Player Setup”. In this menu you can change your multiplayer name, player color, and (in Hexen) player class. Note that this is the game's own menu and not part of Doomsday's UI.
Connecting to a non-public server. To connect to a server that is not announced to the master server, select “Connect to Server…” in the Multiplayer tab's actions menu (“…” under the tab title), and enter the server's IP address or domain name.
Failure to connect? There are several reasons why you may not be able to join a multiplayer game. You will be notified if you don't have the same packages that the server is using. You can review the required packages in the server information popup. Connectivity problems can also be due to your firewall or network address translation (NAT).
Doomsday uses TCP network connections for multiplayer games. If you host a game and are behind a firewall or using NAT, you must make sure that other computers are able to open TCP connections to your computer. This entails opening the appropriate incoming TCP ports on your firewall and/or configuring the NAT so that the correct ports are routed to your computer.
Additionally, UDP ports 13209-13224 are used for detecting servers running on the local network; if you are experiencing problems with autodetecting local servers, check that your firewall isn't blocking these UDP ports on either end.
A server opens one TCP port for listening to incoming connections. The port must be open for incoming TCP traffic in the firewall. The port number is configured with the console variable
net-ip-port. By default, a server uses TCP port 13209.
Clients do not require any firewall configuration for incoming connections. A client only needs to be able to reach the server via the server's TCP port.
You can see status information about the network subsystem with the console command:
Hosting a game. Use Doomsday Shell to host a multiplayer game of your own. The Shell allows you to start, stop, and control Doomsday multiplayer servers. This includes both your own local servers and remote servers on the internet.
doomsday-server runs in a background process and has no UI of its own. The Shell provides a couple of basic game options that you can change via the GUI. For example, you can choose between Deatchmatch and Co-op mode, change the current map, and enable or disable monsters. The full set of console variables can be modified via the Console tab (text-mode command line interface).
If your server is not public (i.e., announced to the master server), a client can connect to it manually using the IP address or domain name.
For more information about the Shell, see Shell Help in the wiki.