When the online mode is enabled on your Minecraft VPS, players must authenticate through the official Minecraft servers from Mojang before joining your server. This verification ensures that players are logged in and can access their profile skins.
If you wish to use BungeeCord or an unofficial client, you will need to disable online mode.
Without online mode, players will not be required authentication, so anyone can log in with any username. To mitigate this risk, make sure to use a plugin like IPWhitelist or FastLogin for Minecraft servers or a mod like Simple Login for modded servers.
Disabling online mode will also prevent profile skins from being retrieved, so all users will appear as either Steve or Alex. To restore profile skins, use a plugin like SkinRestorer.
If you still want to disable online mode after considering these factors and applying all the safety measures, follow the steps below:
On your instance's Main Menu, go to Configuration:
Go to the Server settings section
Click the toggle on the Standalone Server property to turn it off:
Restart your Minecraft server to apply the changes
That's it! Now you are running your server in offline mode.