Upload a world to a server

A server keeps its world as a folder next to the server jar, and it holds that folder open the whole time it is running. Replacing it under a live server is the single most common way people lose a world, so the first step is not optional.

1. 1Stop the server properly — the stop command in the console, or the Stop button in your host's panel. Not a kill or a force restart: those skip the final save.
2. 2Take a backup of the world that is there now, even if you are sure you no longer want it. A copy costs nothing today and answers every question you might have tomorrow.
3. 3Check which version the server runs. A world made in a newer version will not open on an older server, and there is no way round that.

1. 1Unpack the .zip on your own computer first. You want the folder that directly contains level.dat — that folder is the world.
2. 2Open server.properties and read the level-name line. Whatever it says is the folder name the server will look for; on a fresh server it says world.
3. 3Delete or rename the old folder of that name, then upload the new one and give it exactly that name. Names are case sensitive on Linux hosts, which is where most servers live.
4. 4Upload over SFTP or your panel's file manager. If the panel offers a zip upload with unpack-on-server, use it — uploading thousands of small region files one by one is slow and drops connections.
5. 5Start the server and watch the console as it boots. It prints the world it loaded and complains loudly if it could not.

The server does not read the world's spawn point from the map in every case, and a fresh server.properties has no idea where the build is. Stand where players should arrive and run /setworldspawn. There is a fuller explanation in the article on setting the world spawn.