From The Battle for Wesnoth Wiki
The game server runs on TCP port 15000 by default.
Public Official servers
- accepts the most recent stable release of the game, uses the default port 15000
- accepts the most recent development release of the game, uses port 14999
- accepts up-to-date SVN versions of the game, uses port 14998
server.wesnoth.org is the same host as devsrv.wesnoth.org