Multiplayer Change Seed
Changing Seed (Resetting Map)
In order to change the seed of your map, you must first locate the "server.cfg" file and open it with any text editor.
You may change the current number to anything of your choosing, but will reset the server's map.
If you were to switch back over to a previous seed, it will keep your current area explored.
The default seed for multiplayer is 26789.