VTsAutoSync

🔄 VTs Auto Mod Sync
Say goodbye to "Mismatched Mod Channel List" errors forever.
VTs Auto Mod Sync is a server utility mod for Forge 1.16.5 that allows clients to automatically download missing or outdated mods directly from the server before joining. Whether you run a small SMP or a massive modpack server, this mod ensures your players are always up to date without needing to manually distribute zip files.

✨ Key Features
Automatic Synchronization: Detects missing mods, version mismatches, and file corruption.
Large Modpack Support: Battle-tested on packs with 360+ mods (e.g., ATM6).
Smart Download Manager:
Resilient: Retries failed downloads automatically (3 attempts).
Intelligent: Knows the difference between ProjectRed-Core and ProjectRed-Transmission (won't accidentally delete related modules).
Clean: Removes old versions of mods automatically to prevent duplicates.
Subfolder Support: Fully supports servers that organize mods into subfolders.
Crash-Proof: Intercepts the connection after the handshake fails, preventing game crashes and providing a clean, user-friendly download GUI.
Progress Tracking: Shows real-time progress bars and status updates.
🛠️ How It Works
Join: The player attempts to join the server.
Detect: If the player is missing mods, Forge usually kicks them. VTs Auto Mod Sync intercepts this kick.
Sync: A GUI appears listing exactly what is missing.
Download: The player clicks "Download Missing Mods". The files are pulled directly from the server's internal HTTP host.
Play: Once finished, the player clicks "Close Game", restarts, and joins successfully!

📦 Installation & Setup
For the Server Owner
Drop the .jar into your /mods/ folder.
Start the server. It will automatically start a lightweight file server on Port 8000 (default).
CRITICAL: You must Port Forward TCP Port 8000 (or whichever port you choose in the config) so external players can reach the file server.
For the Client (Player)
Drop the .jar into your /mods/ folder.
Join the server!

⚙️ Configuration
The config file can be found at config/vtsautomodsync-common.toml.
code
Toml
[general]
# The TCP Port used for the HTTP File Server.
# Client and Server must have the same port setting.
# Default: 8000
serverPort = 8000
Note: If you change the port on the server, you must include this config file in your modpack so clients know which port to connect to.

❓ FAQ
Q: Does this work with huge modpacks?
A: Yes! It has been tested with 360+ mods. It includes a robust retry system to handle network hiccups during mass downloads.
Q: Why does it say "Connection Refused" when downloading?
A: This usually means the server owner has not port-forwarded the file server port (Default: 8000) on their router/firewall.
Q: Does it delete my other mods?
A: It only deletes old versions of the specific mods it is updating. It uses a smart identity system to ensure it never deletes unrelated mods (e.g., mcw-bridges will never delete mcw-doors).
Q: Is this safe?
A: Yes. It does not modify the core Forge handshake code (which causes instability). It sits on top as a safe layer to handle the disconnect screen.
Found a bug? Please report it on the issue tracker!