Core Keeper keeps its settings in a single file, ServerConfig.json. Everything from the Game ID to the world seed is in there.
1. Open the file
- Stop the server in the Game Panel.
- Open the Files tab and find
ServerConfig.jsonin the dedicated server data folder. If it does not exist, start the server once and stop it again.
2. The settings that matter
| Setting | What it does |
|---|---|
gameId | The code players paste to join. Set your own so it never changes. |
worldName | The name of the world. |
worldSeed | The seed used when a world is first generated. |
worldIndex or world | Which world slot the server loads. |
maxNumberPlayers | Player slots. |
worldMode | The world type, for example normal, hard or creative. |
seasonOverride | Forces a seasonal event on or off. |
3. Setting a permanent Game ID
A generated Game ID changes if the config is reset, and then nobody can find your server. Setting your own avoids that.
- It must be at least 28 characters long.
- It cannot contain the digit zero.
- It cannot contain punctuation. Letters and numbers only.
- Keep it short enough to fit in the join box in game.
Pick something long and unguessable. Anyone with the Game ID can join a server that has no other protection.
4. Save and restart
- Save the file. It must stay valid JSON. A trailing comma or a missing quotation mark stops the server loading it.
- Start the server and check the console for the Game ID and world name.
5. The seed only applies to a new world
Changing worldSeed does nothing to a world that already exists. The terrain has been generated and saved. To use a new seed, point the server at a world slot that has not been used yet, which leaves your existing world on disk untouched.
If a setting does not apply, confirm the server was stopped when you saved and that the file is still valid JSON.





