Online mode is a server setting that determines if players need to authenticate through Mojang’s servers before connecting. This process confirms their login and allows access to profile skins.
Certain server types, like BungeeCord child servers, don't function with online mode enabled, and players with cracked clients can't join. To use BungeeCord or allow cracked clients, you will need to disable online mode on your server.
Warning
Disabling online mode means that players will not be authenticated by Mojang’s servers before they connect to your server. This means that anyone could log in to your server using any username they choose and your server wouldn't verify they are who they say they are.
# Important Notes
As previously mentioned in the warning message, offline servers are insecure and could become an absolute security nightmare if you are not careful. However, there are some options to help remedy this. If you are using a BungeeCord server, a plugin such as IPWhitelist will help mitigate risks. For Minecraft servers, a plugin like FastLogin would help, while modded servers could use a mod such as Simple Login.
In addition to offline servers being insecure, your players will not have their profile skins visible either, and everyone will appear as a default Minecraft skin. Again, this is because your server is not contacting Mojang’s authentication servers. You can use a plugin like SkinsRestorer to restore profile skins in your server if desired.
# Disabling Online Mode
Please ensure you read the warnings above before following these steps!
- Access your server's control panel and navigate to the Files tab.
- Find the server.properties file, and click its name to edit it
- Change the online-mode field to false
- Save the file, then restart your server
That's it! You have successfully disabled online mode for your server. Please keep in mind that disabling online mode makes your server vulnerable to attacks as usernames are no longer verified.
