BeastheimServerMods

Beastheim Server Mods

Server management, character protection, mod enforcement, and community monitoring for Valheim dedicated servers.

Beastheim Server Mods is a collection of configurable server-management tools originally developed for the Beastheim Valheim community.

Built to help server administrators maintain fair progression, manage limited player slots, enforce modpack consistency, and monitor server activity, it combines several essential systems into one plugin.

Features

• Server-Authoritative Characters: Bind each player's character to your server, preventing the normal import of items, equipment, and progression from other worlds. Includes persistent saves, controlled character resets, revision history, backups, and administrative recovery.
• Modpack Enforcement: Check connecting players against the server's required and optional mods. Reject missing, modified, incompatible, or unauthorized plugins with clear, player-facing explanations.
• AFK Detection & Management (optional, off by default): Detect inactive players, issue configurable warnings, and disconnect idle players to free up limited server slots. Includes final-save handling to help protect character progress.
• Discord Webhooks & Monitoring (optional, off by default): Send server status, player connection activity, and administrative alerts to separate Discord channels without blocking gameplay.
• Connection Status & Integration: Provide connection-state information and a limited server-side identity API for other compatible mods.

Built for Beastheim. Available to the Community.

Although developed for Beastheim, the systems are configurable for other Valheim dedicated servers, from private groups to larger multiplayer communities.

Installation: Install on the dedicated server and on every client that connects. The plugin goes in BepInEx/plugins. The server is the authority; clients answer its questions and show its messages. A client without the plugin cannot join a server that enforces it. Requires BepInExPack for Valheim.

Compatibility: Built and tested against Valheim 1.0.17 with BepInExPack 5.4.2350 and 5.4.2351.

> Status. Validated on Valheim 1.0.17 with a real client against a real dedicated server (BepInExPack 5.4.2350): first-join registration, mod-check admission, the character surviving logouts, reconnects and two server restarts byte for byte, a second character being refused with a readable message, and a clean character store afterwards. It has not yet had a long run on a public server, and it is built for modpacks that use the Jotunn library (as the Beastheim pack does). Please report problems with the Beastheim Server Mods lines of the log and what you were doing.

What players see

When the server turns a player away, the main menu shows a dialog titled Cannot join this server with the reason and an OK button (Enter also closes it). Examples:

• A second character on an account: Only one character is allowed per player on this server. Your registered character is <name>. Select that character and join again. Lost your character? Contact a server administrator.
• A mod problem: Beastheim mod check failed. followed by lines such as Install required: ..., Remove not allowed: ... or Update or reinstall: ... naming the mods, and Restart Valheim after changing mods, then try again.

The dialog is drawn by this mod with the game's own font, because the game's built-in connection-failed panel is shared with the game and other mods and can come out blank. A player without this mod installed cannot receive the reason and sees the game's stock "Incompatible version" message instead.

Quick start for server operators

1. Install this mod on the server and give every player the same modpack that includes it.
2. Put the original DLL of every mod players must run in BepInEx/config/BeastheimServerMods/required/ (one folder per mod is fine), and any mod players may add in optional/.
3. In BepInEx/config/beastheim.servermods.cfg set [Enforcement] Mode = Enforce and [Characters] Mode = Enforce, then start the server.
4. Join with a test client first. Check the server log for Beastheim Server Mods ... loaded and Policy loaded: N required.
5. Back up BepInEx/BeastheimCharacters (see Backups below). It is not part of the world save.

Start with Mode = WarnOnly if you want to see what would be refused before refusing anyone.

1. The mod check

Policy is two folders of the mods' own DLL files on the server:

BepInEx/config/BeastheimServerMods/required/   every client must have these, identical
BepInEx/config/BeastheimServerMods/optional/   a client may have these, identical if present

Copy each mod's original, unmodified DLL from its Thunderstore download into the right folder. Do not copy files from a compatibility or shadow cache. Edits to the policy folders are picked up live; no restart is needed.

At connection time the client reports every plugin it has loaded with a hash of its file. The server compares that with the folders and decides:

| Situation | Result | |---|---| | Everything required is present and identical, nothing unlisted | Admitted | | A required mod is missing, wrong version or modified | Refused, naming the mod | | A mod that is in neither folder | Refused (BlockUnlistedPlugins) | | No plugin report at all (no Beastheim Server Mods) | Refused (MissingManifestPolicy) | | Anything unexpected inside the server | Refused (InternalErrorPolicy = Reject): it never waves players through on an error | | Both policy folders empty or missing | Refused (EmptyPolicyBehavior = Reject, the default). Allow exists only for a throw-away test server that has no mod list yet |