Valheim Server Hosting Guide — Mods, World Migration & Multiplayer Tips

Why Use a Dedicated Valheim Server?

Valheim's peer-to-peer multiplayer has a fundamental problem: the host must be online for anyone else to play, and performance degrades quickly past 3-4 players because the host's PC is running both the game and the server. A dedicated server fixes this — your world runs 24/7, anyone can join anytime, and server hardware handles the load instead of someone's gaming rig.

Visit our Valheim server hosting page to see available plans and features.

RAM and Hardware Requirements

Valheim is relatively lightweight compared to games like ARK or Palworld, but modded servers need more headroom:

• Vanilla, 1-5 players: 2 GB RAM minimum. This handles the base game comfortably.
• Vanilla, 6-10 players: 3-4 GB RAM. More explored terrain means more world data in memory.
• Modded with BepInEx, 1-5 players: 4 GB RAM. Mods add overhead, especially ones that add new entities or terrain features.
• Heavily modded, 6-10 players: 4-6 GB RAM. If you're running 20+ mods including Valheim Plus and content mods, give it room to breathe.

CPU:1-2 cores at 3.0 GHz or better. Valheim isn't as CPU-intensive as Minecraft, but it still needs consistent processing power for terrain generation and entity updates.

Disk: 10 GB minimum. World files start small but grow as players explore. A fully explored map can reach 500 MB+.

Server Configuration

Valheim uses startup parameters rather than a config file for most settings. Here are the key options:

• -name "My Valheim Server" — The server name shown in the browser. Pick something your friends can find easily.
• -world "MyWorld" — The world file name. Changing this creates a brand new world. Use this to run multiple worlds on the same server.
• -password "yourpassword" — Required. Must be at least 5 characters. Cannot contain the server name — this trips people up constantly.
• -port 2456 — Primary port. The server also uses port+1 (2457) for Steam queries. Both must be open.
• -public 1 — Set to 1 to list in the community server browser, 0 for private (join via IP only).
• -crossplay — Enable crossplay between Steam and Xbox/Game Pass/Microsoft Store players. Omit this flag for Steam-only.
• -savedir "/path/to/saves" — Custom save location. Useful for backup scripts.

Port Forwarding Explained

If you're self-hosting (running the server on your own hardware or a VPS), you need to open the right ports. Valheim uses three consecutive UDP ports:

• 2456 (UDP) — Game traffic. This is the port players connect to.
• 2457 (UDP) — Steam server queries. Required for the server to appear in the community browser.
• 2458 (UDP) — Steam master server communication.

On managed hosting (like kranky.io), these ports are already configured for you. If you're self-hosting, you need to:

1. Open UDP ports 2456-2458 in your OS firewall (ufw allow 2456:2458/udp on Ubuntu).
2. Forward these same ports on your router (access your router admin panel, usually at 192.168.1.1).
3. Give players your public IP address (find it at whatismyip.com) and port 2456.

Worried about exposing your server to attacks? Read our guide on DDoS protection for game servers to understand the risks and how to mitigate them.

BepInEx Mod Setup — Step by Step

BepInEx is the universal mod framework for Valheim. Every Valheim mod depends on it. Here's how to install it on a dedicated server:

1. Download BepInEx: Get the latest Valheim BepInEx pack from Thunderstore. Make sure you get the correct version — there's a specific Valheim pack, not the generic BepInEx release.
2. Upload to server: Extract the zip and upload all files to your Valheim server's root installation directory (where valheim_server.exe or valheim_server.x86_64 lives). The key files are winhttp.dll (Windows) or run_bepinex.sh (Linux) and the BepInEx/ folder.
3. First run: Start the server once with BepInEx installed. It will generate config files in BepInEx/config/. Shut it down after it finishes loading.
4. Install mods: Drop mod DLL files into BepInEx/plugins/. Each mod is usually a single .dll file or a folder containing one.
5. Configure mods: After the first run with a new mod, check BepInEx/config/ for a config file with the mod's name. Edit this to customize the mod's settings.
6. Restart: Restart the server to load the mods. Check the console or BepInEx/LogOutput.log to verify mods loaded successfully.

Critical: Players must have the same mods installed on their client. Use Thunderstore Mod Manager or r2modman to create a mod profile that everyone can import.

Popular Valheim Mods Worth Running

• Valheim Plus: The essential quality-of-life mod. Shared map exploration (huge for multiplayer), advanced building mode with a free-form camera, configurable game settings (stamina, carry weight, XP rates), and dozens of other tweaks. Server-side and client-side.
• Better Networking / Network Fix: Compresses network data and optimizes packet handling. Reduces lag and desync in multiplayer. Highly recommended for servers with 5+ players.
• Plant Everything: Lets players plant mushrooms, thistles, berries, and other vegetation that's normally un-plantable. Popular for building self-sustaining bases.
• Epic Loot: Adds a Diablo-style loot system with magical items, rarity tiers, and set bonuses. Changes the late-game loop significantly.
• Server Devcommands: Enables admin commands without turning on devcommands for everyone. Essential for server admins who need to manage the world without giving all players creative powers.
• Creature Level and Loot Control: Adds more creature star levels and scales loot accordingly. Makes exploration more rewarding and dangerous.

World Migration — Uploading Your Existing World

Already have a local world you want to move to a dedicated server? Here's how:

1. Find your local world files. On Windows, they're in %appdata%/../LocalLow/IronGate/Valheim/worlds_local/. You need two files: YourWorldName.fwl and YourWorldName.db.
2. Stop your server if it's running. Never upload files to a running server.
3. Upload both files to the server's world directory. On Linux, this is typically ~/.config/unity3d/IronGate/Valheim/worlds_local/. On managed hosting, use the file manager in your control panel.
4. Update the startup parameter -world to match your world file name (without the extension). If your files are MyViking.fwl and MyViking.db, use -world "MyViking".
5. Start the server. It should load your existing world with all builds and progress intact.

Note:Player character data (inventory, skills) is stored locally on each player's machine, not in the world file. Everyone keeps their character progress when connecting to the migrated world.

Performance Tips

• World size matters: The more terrain players have explored, the larger the world file and the more memory it uses. On a 2 GB server, you'll eventually feel the impact of a fully-explored map. Plan for 4 GB if your group likes to explore.
• Entity cleanup: Hundreds of dropped items, tamed animals, and structures affect performance. Periodically clean up abandoned builds and item drops. Mods like "Auto Pickup" help prevent item clutter.
• Limit terraforming: The terrain modification system (flattening, raising ground) adds data to the world file. Excessive terraforming around bases can cause local lag. The "OptTerrain" mod helps compress existing terrain modifications.
• Restart schedule: Restart the server every 12-24 hours. Valheim's memory usage creeps up over long sessions as the world simulation accumulates state.
• Backup before updates: Valheim patches occasionally break world compatibility. Always back up your .fwl and .db files before allowing the server to update.

Frequently Asked Questions

My world isn't saving / I lost progress

Valheim autosaves every 20 minutes. If you're losing progress, the server might be crashing before it can save. Check your server logs for errors. Force a save by restarting the server gracefully (don't hard-kill the process). If using mods, a broken mod can sometimes prevent saves — check BepInEx/LogOutput.log for errors.

Mods aren't loading on the server

• Verify winhttp.dll (Windows) or run_bepinex.sh (Linux) is in the server root directory.
• Check BepInEx/LogOutput.log — it will tell you exactly which mods loaded and which failed.
• Make sure the mod version matches your Valheim version. After a game update, mods often need updating too.
• On Linux, make sure run_bepinex.sh is executable (chmod +x run_bepinex.sh) and that the server is started through it, not directly.

Server doesn't appear in the browser

• Make sure -public 1 is set in your startup parameters.
• Check that UDP ports 2456-2458 are all open (not just 2456).
• It can take up to 10 minutes for a new server to appear in the community list. Have players try connecting via IP directly first.
• If using crossplay (-crossplay flag), Steam and Xbox players search in different server browsers.

Players getting "Incompatible version"

The server and all clients must be on the same Valheim version. When the game updates on Steam, your server needs to update too. On managed hosting, this usually happens automatically. If self-hosting, update via SteamCMD. Tell your players to hold off on updating until you confirm the server is updated — and that all mods are compatible with the new version.