Barotrauma drops your crew into a submarine navigating the oceans of Europa, Jupiter's moon. Communication, teamwork and occasional sabotage from a traitor make it one of the most intense co-op experiences available. A dedicated server lets up to 16 players run ongoing campaigns without relying on one person to host every session.
System requirements
- RAM: 4 to 8 GB. Campaign servers with many rounds and active creatures need the higher end. A short mission-based server runs fine on 4 GB.
- CPU: 2 to 4 cores. Physics calculations for water flooding and creature AI are the main CPU consumers.
- Storage: 3 to 5 GB for the server files and save data.
- Network: Port 27015 UDP (game traffic) and 27016 UDP (Steam query). Low latency is important for the real-time physics.
HostValues servers with AMD Ryzen 9 7950X and NVMe storage give you the fast single-thread performance and I/O speed that Barotrauma benefits from.
Installation
- Install SteamCMD on your VPS, or pick Barotrauma in the HostValues game panel.
- Download the dedicated server with
app_update 1026340 validate. The server shares an app ID with the client. - Open ports 27015 and 27016 UDP in your firewall.
- Run
./DedicatedServeron Linux. The server launches a text-based configuration wizard on first start. - Set a server name, password (optional), and choose your game mode: Sandbox, Mission, or Campaign.
Game modes
- Campaign: An ongoing story with persistent crew progression, money, upgrades and reputation. Best for a regular group that plays together often.
- Mission: Individual missions without persistence. Good for pickup games and public servers.
- Sandbox: Free play with no objectives. Useful for testing submarines or practising systems.
Server configuration
Server settings live in serversettings.xml. Important entries:
| Setting | Description |
|---|---|
| MaxPlayers | Maximum crew size, up to 16. |
| AllowRespawn | Whether dead players respawn during a round. |
| TraitorProbability | Chance that a round includes a traitor. Set to 0 to disable. |
| SubSelection | Whether players vote on the submarine or the host picks one. |
| RespawnInterval | Seconds between respawn shuttle arrivals. Lower values are more forgiving. |
Submarine selection
The submarine you choose shapes the entire gameplay experience. Smaller subs like the Dugong are easier to manage with a small crew but cramped during emergencies. Larger vessels like the Berilia or Kastrull have more systems to manage, meaning more jobs for each crew member and more room for things to go wrong. For a new crew, start with a medium sub so everyone has something to do without being overwhelmed.
Custom submarines built in the submarine editor can be used on dedicated servers. Place the sub file in the Submarines directory and it becomes available for selection. The community has published thousands of custom designs on the Steam Workshop, from realistic military vessels to absurd contraptions that barely float.
Mods and Lua scripting
Barotrauma supports Steam Workshop mods on dedicated servers. Add mod IDs to the server's mod list in the configuration file. The game downloads them on startup. Popular mod categories include new creatures, expanded crafting recipes, additional missions, and quality-of-life improvements like better wiring tools.
For deeper customization, Barotrauma supports Lua scripting. This lets you write custom events, modify game mechanics, and create new content without recompiling anything. Lua mods load from the server's mod folder. The Lua API gives access to nearly every game system, which makes Barotrauma one of the most moddable co-op games available.
Performance optimization
- Large submarines with many rooms and systems use more CPU. If performance suffers, try a smaller sub.
- Creature-heavy biomes (the Abyss) are the most demanding. Limit expedition depth if your server struggles.
- Restart between campaigns or after long sessions. The server accumulates state data over time.
- NVMe storage helps with campaign save times. Saving a long-running campaign on slower storage can cause brief hitches.
- Water physics is the heaviest simulation in Barotrauma. A hull breach with multiple compartments flooding simultaneously is the peak load moment. Ensure your server has at least 2 dedicated cores so the physics thread does not starve.
For campaign servers that run for weeks, schedule a daily restart via cron. This clears accumulated state and keeps connection quality consistent for your crew.
Can I run a campaign and a sandbox server at the same time?
Yes, on separate ports. Run two server instances with different configurations. Make sure your plan has enough RAM for both. On a HostValues VPS you have full control over port allocation.
How does the traitor system work on a dedicated server?
The server randomly assigns a traitor role based on the TraitorProbability setting. The traitor receives secret objectives. Set the probability to 0 for pure co-op or raise it for more tension.
Why do players rubber-band or desync?
Barotrauma's physics are sensitive to latency. Choose a server location close to your group and make sure DDoS protection is active so traffic spikes do not interfere. HostValues includes DDoS protection on all plans.
Can I use custom submarines on the server?
Yes. Place custom submarine XML files in the server's Submarines folder. They appear in the sub selection screen. Workshop submarines can also be added through the mod system.
Dive into Europa on a HostValues VPS with the CPU power and DDoS protection your crew needs.
