Your players find your Core Keeper server from inside the game. Core Keeper is a co-op survival sandbox about mining, building, crafting and fighting through an endless underground world; a hosted server keeps your world online so friends can join without anyone having to keep the game open.
Join in a few steps
- Open your server in the panel. If the status badge says Offline, click Start and wait until it says Online. See How to start, stop, restart and force-stop your server.
- Launch Core Keeper.
- Find your server's Game ID. If you set one in Settings, then Game Settings, use that. If you left Game ID empty, start the server, wait until the world has finished loading (a few minutes on the first start), then open Files and read the single line in GameID.txt. That line is your code.
- From the main menu in the game, choose Join Game.
- Enter the Game ID and confirm. Players do not type the address or port from the Overview page for this game.
- Next time, look in the list of servers you joined before and pick yours instead of typing the code again.
- If the game does not accept the Game ID, check that it matches the code in Game Settings or in GameID.txt exactly, and that the server was restarted after you changed it. If it still fails, ask support.
Ports
Players join with the Game ID rather than the address and port. If you leave the Game ID setting empty, the server picks a code for you when it starts and writes it to GameID.txt in Files, and it can pick a different one after a restart. Set your own Game ID in Settings, then Game Settings, so the code stays the same.
Game version
Core Keeper updates arrive through Steam. By default the server checks for a new game build every time it starts, and your world and settings are not touched by that, so restart the server after a game update. If you turn Auto Update off, the server stays on its current build until you turn it back on and restart.
If you cannot join
- The server must be Online. Check the badge at the top of the page.
- Make sure every player runs a compatible game version.
- More checks: How to join your server and Core Keeper server problems and fixes.
