Run a dedicated server

KCDCServer hosts the session, holds the authoritative world state and runs your resources. It is the same program on your desk and on a rented machine. To get the default gamemode running locally for the first time, follow Install and run a server instead.

Linux, in server-linux/

./KCDCServer

Windows, in server/

.\KCDCServer.exe

Start it from its own folder: it reads server.json and resources/ from the working directory, not from next to the binary. The first start writes a server.json with every default. The server accepts players once the log shows:

KCDC Server successfully started

Stop it with Ctrl+C, quit in the console, or SIGTERM. All three run the same shutdown, so resources get their resourceStop handlers.

Prefer Docker?

Every release also publishes a ready-to-run image, ghcr.io/kingdomsconnected/kcdc-server:<version>. See Docker and panels.

The gamemode ships as source

resources/kcdc-gamemode is TypeScript with no dist/, so the server skips it until you build it. See Install and run a server.

What is in the server folder

Folder	Contents
server/ (Windows)	KCDCServer.exe, libnode.dll, crashpad_handler.exe, resources/
server-linux/	KCDCServer, libnode.so.*, crashpad_handler, resources/

The server carries its own JavaScript runtime in libnode, so the host needs no Node.js. On Linux it also links against the system’s libcurl, OpenSSL 3, zlib and libstdc++ (on Ubuntu 24.04: libcurl4t64, libssl3t64, zlib1g, libstdc++6, as in the official container image).

Build resources on any machine and copy the folder, dist/ included, to the server.

Ports

Port	Protocol	What it carries
27015	UDP	The game session: connection, replication, resource and custom asset downloads, voice
27016	TCP	HTTP endpoints, including a status document at /

Nothing listens on TCP 27015. Change the ports with --port and --apiport, or port and apiport in server.json. To let players in from outside, see Let players connect.

Check that a server is up without starting the game:

Any terminal

curl http://your.server.address:27016/

It answers with JSON: mod name and version, game port, max_players and the replicated mod settings such as the level.

Player limit

A session holds at most 512 players. The cap is compiled in: maxplayers can lower it, but a larger value is clamped to 512 at boot with a warning.

Command-line arguments

Options override the matching server.json key for one run and are never written back:

Linux, a second server on the same machine

./KCDCServer --port 28015 --apiport 28016 --config second.json

Options and overrides lists every option, which source wins, and how to change common behaviours.

Resources and chat commands

Every folder under resources/ with a valid package.json is a resource, started at boot (Resources).

The server itself answers no chat commands: /help, /tp and the rest come from kcdc-gamemode. Without it players still connect and play, but commands do nothing. Plain chat is relayed to everyone by default either way (Chat and /commands).

Console commands

The server reads operator commands from standard input: its terminal, or a hosting panel’s console tab. help in the console goes to the server; /help in game goes to your resources.

Server console

ensure my-resource

Verb	What it does
start <resource>	Start a stopped resource
stop <resource>	Stop a running resource
stop	With no argument, shut the server down
restart <resource>	Reload a running resource. Refuses if it is not running
ensure <resource>	Reload the resource if running, start it if not
refresh	Register new folders in resources/, stopped
refreshall	refresh, then reload every running resource
quit	Shut the server down
status	Print server name, address and player count
help	List every verb

<resource> is the name in its package.json, normally the folder name.

stop on its own stops the server

stop kcdc-gamemode stops one resource; a bare stop shuts everything down, like quit.

Reload a resource

A reload runs the resource’s resourceStop handlers, removes its listeners and timers, forgets its cached modules, re-reads package.json and starts it again. Resources that depend on it restart with it.

Players stay connected: they receive the changed client files and restart the client half in place. Scripts and tooling usually want ensure, which also works when the resource is not running.

Add a resource while the server runs

start only knows resources found so far. Scan for a newly copied folder first; refresh never starts anything itself:

Server console

refresh
start my-new-resource

In a container the console needs stdin and a terminal attached; see Docker and panels.

Files the server writes

Everything lives in the working directory: server.json, resources/, logs/, .packages/ and crash data. Back up the whole folder, hidden files included. Options and overrides says what each one is.

Related

• Options and overrides: every option and setting, and which one wins.
• server.json settings: every key, the level and required DLCs.
• Let players connect: port forwarding and what to send players.
• Docker and panels: the official image.
• Write your first resource: the edit, build, ensure loop.