The world data, including player inventories, is saved in a folder within the current working directory.
The name of said folder depends on the level-name setting in server.properties, and defaults to world. You can create a new save and toggle between them by changing this setting.
Vanilla server commands for saving/backups
/save-all - forces the server to save. rock it like a hurricane /save-off - disables saving. You should definitely execute this before making a backup of a running server to ensure that the server doesn't save while you're copying, which could result in a corrupt backup. /save-on - re-enables saving.
Thank you! I hadn't thought to disable saving while creating a backup. - aedia Jun 22, 2011 14:27
i saved the server to my desktop so were will the directory be?? - user14851 Nov 20, 2011 at 8:22
Do you know if it is possible to run the saveoff and save-on commands using a batch job? - mpontillo Apr 26, 2012 at 14:53
@Mike If you're just looking for an automated way to make backups, you can look into plugins to do this such as Bukkit Backup or other Bukkit backup plugins. I recommend mcrcon which allows you to remotely execute commands. Schism Sep 8, 2012. 19:23
The world folder should be located within the directory where the server is running. There should be a world folder that contains all the files your server requires to run. The world folder contains all the "block data", so it is important to backup the region folder. Another folder within the world directory is the players folder, which stores informations about the players that connect (inventories, etc). (Note that the directory is only named world if you haven't changed the level-name property in server.properties.)
This information is true of a Vanilla and a Bukkit multiplayer server.
Backup the entire world directory.