Your Core Keeper world is the thing you cannot get back if it is lost, so back it up before you change settings, install mods or update.
Before you start: stop the server so the backup holds complete files. See How to start, stop, restart and force-stop your server.
Where the world is stored
Your world is not saved next to the game files. It is in the game's own save folder, .config/unity3d/Pugstorm/Core Keeper/DedicatedServer/worlds inside Files (the folder name starts with a dot, so look near the top of the list or use the Files search box), with one file per save slot named by the slot number. The same DedicatedServer folder also holds the server config, the admin list (Admins.json) and the ban list.
Make a backup
- Open your server in the panel and click Backups in the left menu.
- Click Start backup with Files selected. The backup copies the whole server folder, so the world is included.
- To keep a copy outside PlayNHost, open the ... menu of the backup and choose Download.
The server folder also holds the game's own files, which can be large, so check the size on the Backups page. If it does not fit your backup space, ask support what to leave out. Do not guess an ignore pattern, because a wrong one can leave your world out of the backup. See How to create, download and restore backups for scheduling, locking and limits.
What to make sure is included
Back up the whole DedicatedServer folder, not only worlds. That keeps the world file together with your admin list, ban list and server config. If you run several worlds, the worlds folder holds one file per slot.
Restore a backup
A restore replaces the current files with the backup, and anything changed since is lost. Take a fresh backup of the current state first if you may want it back.
Choose Restore to server from the backup's ... menu, confirm, and start the server when it finishes.
To bring a world from another computer instead, see How to upload your own Core Keeper world.
