First of all, you can compile STK with `-DSERVER_ONLY=ON` which will produce a GUI-less STK binary optimized for size and memory usage, useful for situation like in VPS.
It is recommended you have a saved user in your computer to allow hosting multiple servers simultaneously with the same account, if you have a fresh STK installation, first run:
It will create that xml configuration file if not found in current directory, you can type `quit` in terminal, than you can edit that file for further configuration as required.
The current server configuration xml looks like this:
<!-- Name of server, encode in XML if you want to use unicode characters. -->
<server-namevalue="stk server"/>
<!-- Port used in server, if you specify 0, it will use the server port specified in stk_config.xml or if random-server-port is enabled in user config, than any port. STK will auto change to random port if the port you specify failed to be bound. -->
<server-portvalue="0"/>
<!-- Game mode in server, 0 is normal race (grand prix), 1 is time trial (grand prix), 3 is normal race, 4 time trial, 6 is soccer, 7 is free-for-all and 8 is capture the flag. Notice: grand prix server doesn't allow for players to join and wait for ongoing game. -->
<server-modevalue="3"/>
<!-- Difficulty in server, 0 is beginner, 1 is intermediate, 2 is expert and 3 is supertux (the most difficult). -->
<server-difficultyvalue="0"/>
<!-- Number of grand prix tracks per game (If grand prix enabled). -->
<!-- Clients below this value will be rejected from joining this server. It's determined by number of official karts in client / number of official karts in server -->
<official-karts-thresholdvalue="1"/>
<!-- Clients below this value will be rejected from joining this server. It's determined by number of official tracks in client / number of official tracks in server, setting this value too high will prevent android players from joining this server, because STK android apk has some official tracks removed. -->
<!-- Only auto start kart selection when number of connected player is larger than or equals this value, for owner less or ranked server, after start-game-counter reaches 0. -->
<!-- Enable team choosing in lobby in team game (soccer and CTF). If owner-less is enabled and live-players is not enabled, than this option is always disabled. -->
<!-- If strict-players is on, no duplicated online id or split screen players are allowed, which can prevent someone using more than 1 network AI with this server. -->
<strict-playersvalue="false"/>
<!-- Server will submit ranking to stk addons server for linear race games, you require permission for that. validating-player, auto-end, strict-player and owner-less will be turned on. -->
<!-- If true, the server owner can config the difficulty and game mode in the GUI of lobby. This option cannot be used with owner-less or grand prix server, and will be automatically turned on if the server was created using the in-game GUI. The changed difficulty and game mode will not be saved in this config file. -->
<!-- If true, players can live join or spectate the in-progress game. Currently live joining is only available if the current game mode used in server is FFA, CTF or soccer, also no addon karts will be available for players to choose, and official-karts-threshold will be made 1.0. -->
<!-- Value used by server to automatically estimate each game time. For races, it decides the lap of each race in network game, if more than 0.0f, the number of lap of each track vote in linear race will be determined by max(1.0f, auto-game-time-ratio* default lap of that track). For soccer if more than 0.0f, for time limit game it will be auto-game-time-ratio * soccer-time-limit in UserConfig, for goal limit game it will be auto-game-time-ratio * numgoals in UserConfig, -1 to disable for all. -->
<!-- Kick idle player which has no network activity to server for more than some seconds during game, unless he has finished the race. Negative value to disable, and this option will always be disabled for LAN server. -->
<!-- Set how many states the server will send per second, the higher this value, the more bandwidth requires, also each client will trigger more rewind, which clients with slow device may have problem playing this server, use the default value is recommended. -->
<!-- Database filename for sqlite to use, it can be shared for all servers created in this machine, and stk will create specific table for each server. You need to create the database yourself first, see NETWORKING.md for details -->
<!-- Ip ban list table name, you need to create the table first, see NETWORKING.md for details, empty to disable. This table can be shared for all servers if you use the same name. -->
<!-- Online ID ban list table name, you need to create the table first, see NETWORKING.md for details, empty to disable. This table can be shared for all servers if you use the same name. -->
<!-- Player reports table name, which will be written when a player reports player in the network user dialog, you need to create the table first, see NETWORKING.md for details, empty to disable. This table can be shared for all servers if you use the same name. -->
<!-- IP geolocation table, you only need this table if you want to geolocate IP from non-stk-addons connection, as all validated players connecting from stk-addons will provide the location info, you need to create the table first, see NETWORKING.md for details, empty to disable. This table can be shared for all servers if you use the same name. -->
At the moment STK has a list of STUN servers for NAT penetration which allows players or servers behind a firewall or router to be able to connect to each other, but in case it doesn't work, you have to manually disable the firewall or port forward the port(s) used by the STK.
By default STK servers use port `2759`. For example, in Ubuntu based distributions, run the following command to disable the firewall on that port:
In LAN network it is required that the server and server discovery port is connectable by clients directly, no NAT penetration will be done in LAN.
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After the first time configuration, you can just start the server with the command:
`supertuxkart --server-config=your_config.xml`, regardless of whether LAN or WAN server is chosen (of course you need to have a saved user for the WAN one), by default your server logging will be saved to the STK configuration directory with a name of `your_config.log`, given that the server configuration filename is `your_config.xml`.
You can find out that directory location [here (See Where is the configuration stored?)](https://supertuxkart.net/FAQ)
There is a network AI tester in STK which can use AI on player controller for server hosting linear races game mode, which helps automating the testing for servers, to enable it use:
x.x.x.x:y is your server ip address with its port, id is the id field of server-info in STK server xml list, omit it if you are testing LAN server, n is the number of AI you want to create.
You can remove `--auto-connect` if you have another client which can control the starting of games in server, or you can consider enable owner-less mode on server so the games on server can keep going. Remove `--no-graphics` if you want to see the AI racing. You can also run network AI tester in server-only build of STK.
Tested on a Raspberry Pi 3 Model B+, if you have 8 players connected to a server hosted on it, the usage of a single CPU core is ~60% and there are ~60MB of memory usage for game with heavy tracks like Cocoa Temple or Candela City on the server, you can use the above figures to consider number of STK servers hosting on a same computer.
For bad network simulation, we recommend `network traffic control` by linux kernel, see [here](https://wiki.linuxfoundation.org/networking/netem) for details.
You need to create a database in sqlite first, run `sqlite3 stkservers.db` in the folder where (all) your server_config.xml(s) located.
STK will automatically create a table named `v(server database version)_(your_server_config_filename_without_.xml_extension)_stats` in your database if not exists:
```sql
CREATE TABLE IF NOT EXISTS (table name above)
(
host_id INTEGER UNSIGNED NOT NULL PRIMARY KEY, -- Unique host id in STKHost of each connection session for a STKPeer
ip INTEGER UNSIGNED NOT NULL, -- IP decimal of host
port INTEGER UNSIGNED NOT NULL, -- Port of host
online_id INTEGER UNSIGNED NOT NULL, -- Online if of the host (0 for offline account)
username TEXT NOT NULL, -- First player name in the host (if the host has splitscreen player)
If you want to see flags and readable names of countries in the above views, you need to initialize `v(server database version)_countries` table, check [this script](tools/generate-countries-table.py).
