Core Keeper Dedicated Server Setup and Direct Connect Guide

The official Core Keeper Dedicated Server supports independent, persistent hosting while players are offline. The game offers two distinct networking modes: Game ID mode, based on Steam P2P relays, and Direct Connect mode, based on public IP or LAN connections. This article covers when to use each mode, their settings, and maintenance standards.

1. Compare the two connection architectures

Connection mode	Startup arguments	Network requirements	Latency and NAT traversal	Use cases
Game ID mode (default)	No direct IP connection required	No public IP or router forwarding needed	Traffic passes through Steam relay servers; performance may fluctuate across regions	Dormitories, no public IPv4, quick sessions with friends
Direct Connect mode	Enable direct connections in configuration and open ports	Public IP / port forwarding, or a virtual LAN (such as LanGame OS LINK)	Direct P2P with very low latency, unaffected by relay congestion	Long-term cloud hosts, regular group servers, demanding mining and combat

2. Install the dedicated server with SteamCMD

Download the dedicated server through SteamCMD (AppID 1963720):

Shell

steamcmd +login anonymous +app_update 1963720 validate +quit

After the download, the main executable is CoreKeeperServer.exe on Windows and CoreKeeperServer on Linux.

3. Network ports and Direct Connect configuration

1. Default communication ports

Main game port: UDP 27015
Query port: UDP 27016

2. Main configuration file: `ServerConfig.json`

Located in the server root, with the following key settings:

JSON

{
  "gameId": "",
  "worldIndex": 0,
  "worldName": "LanGameCoreWorld",
  "worldMode": 0,
  "maxPlayers": 8,
  "password": "your_secure_password",
  "network": {
    "directConnect": true,
    "ip": "0.0.0.0",
    "port": 27015
  }
}

Fields:

worldMode: World difficulty; 0 is standard and 1 is hardcore.
directConnect: true forces direct IP connections; false asks Steam to generate a 28-character Game ID string.
port: UDP listening port in direct mode; allow it in the firewall and forward it on the router.

4. Startup script and running the server

Create launch.bat:

Batch

@echo off
CoreKeeperServer.exe -logfile "server.log"

After startup:

Without Direct Connect, the console and log print a value such as Game ID: XXXXX-XXXXX-XXXXX-XXXXX-XXXXX. Share it with friends, who can enter the ID in the main menu to join.
With Direct Connect enabled, players join through IP:27015.

5. Choose an approach: manual configuration or LanGame Server Manager (LGSM)

Manual Core Keeper maintenance requires frequent JSON edits when switching between Game ID and direct mode, while logs are spread across different paths.

We recommend the official open-source dedicated server management platform to automate routine administration:

Tool overview and client: LanGame Server Manager (LGSM) product page
Open-source repository: GitHub - SZSLGJCOM/LanGame-Server-Manager

LGSM provides:

One-click mode switching: Switch visually between Game ID and direct IP modes in seconds.
Automatic Game ID extraction: Captures the Game ID from standard output after startup and highlights it on the dashboard for one-click copying and sharing.
Scheduled world save archives: Packages the world save directory automatically to protect against mistakes after extensive terrain destruction while mining.
Self-healing supervision: Detects process status in the background and restarts after system updates or unexpected exits.

6. Common issues during long-term operations

1. Game ID mode reports "Unable to connect to relay server"

Cause: Steam P2P relay service resolution can slow down for some Chinese ISPs at certain times.
Solution: Switch to Direct Connect and open UDP 27015, or use LanGame OS LINK to establish a virtual LAN for direct connections.

2. Locate the save path

World data is stored by default at:

Windows: %USERPROFILE%\AppData\LocalLow\Pugstorm\Core Keeper\DedicatedServer\worlds\
Linux: ~/.config/unity3d/Pugstorm/Core Keeper/DedicatedServer/worlds/ To back up, package the 0.world file in that directory.