Anti Alt Server

🛡️ Kyo Anti-Alt (Standalone Security Module)

Kyo Anti-Alt is a lightweight, high-performance server-side mod developed specifically for Minecraft 26.3 (Fabric – Mojang Mappings). It is designed to protect the server economy and completely eliminate the issue of alt accounts (clones) used for grinding or griefing by implementing an "IP Shield" mechanism: permanently binding a single IP address to exactly one unique UUID.

✨ Breakthrough Features

• 🔒 Exclusive Hard-Lock Mechanism (1 IP = 1 UUID): Automatically captures the player’s IP address upon their first login and strictly binds that IP to the account’s UUID.
• 🚫 Iron-Clad Login Blocking: Any secondary account (or clone) attempting to connect from a locked IP is immediately kicked during the login phase, accompanied by a clear notification identifying the primary account associated with that IP.
• 🌐 100% Server-Side Operation: Players using the Vanilla client require no additional mods. It offers perfect compatibility for Bedrock Edition players (mobile, console) connecting via GeyserMC and Floodgate.
• ⚡ Optimized Performance: The lookup system utilizes a thread-safe ConcurrentHashMap structure combined with asynchronous disk I/O (via the GSON library), ensuring the server maintains a steady 60 TPS even under heavy load.
• 🛠️ Administrator-Friendly: Supports in-game and console commands to flexibly remove IP bindings when players have legitimate reasons to switch accounts. —

💻 Administration Command System

The command system utilizes Mojang’s native Brigadier processing library, ensuring instantaneous command response times.

Note: This command can be executed directly from the VPS/Hosting console without needing to log into the game.

📂 Database & Configuration (kyo_anti.alt.json)

Upon the server’s initial launch, the mod automatically generates a data storage file at config/kyo_antialt.json.

The file features a clear, hierarchical JSON structure; administrators can manually edit it using Notepad while the server is offline:

{
"26.165.220.5": {
"uuid": " ",
"name": " "
},
"112.4.22.19": {
"uuid": " ",
"name": " "
}
}