There is no single “best” Barotrauma server configuration. The right setup matches your crew size, tolerance for failure, and whether sessions are social, competitive, or role-play focused. For a private crew of two to four people, set MaxPlayers to the number of humans you expect, leave BotCount at zero unless a missing role makes the submarine unworkable, enable AllowRespawn, and keep the respawn shuttle enabled. Use a campaign as the default for a continuing group, then tune resources and hazards instead of relying only on a difficulty label.
Persistent behavior is stored in serversettings.xml, which is used by both dedicated and client-hosted servers. The lobby exposes some of the same choices, but the file remains the authoritative place to check ports, player limits, bots, voting, moderation, voice chat, missions, and recovery settings. The official pages consulted for these controls report game version 1.13.4.0; because the configuration and dedicated-server pages carry freshness caveats, verify field names and defaults after every major update.
What should you set first for a new Barotrauma group?
Start with capacity, recovery, and game mode. Those choices determine whether a short connection problem becomes a recoverable setback or ends a campaign, and whether empty submarine stations are filled by people or automation.
| Group profile | Capacity and bots | Recovery | Mode and social settings |
|---|---|---|---|
| Small private crew (2–4 humans) | MaxPlayers equal to the expected human count; BotCount=0 unless a role is essential |
AllowRespawn on; UseRespawnShuttle on for a first campaign |
Campaign; password-protected; explain any unusual rules in the description |
| Larger or drop-in crew | Use the human capacity you actually need; consider BotSpawnMode=Fill |
Choose an interval and transport limit that do not leave late joiners idle | Define AFK handling, vote-kick, and round-ending votes before the first session |
| Competitive or role-play group | Use only the capacity required for the agreed roster | Set recovery deliberately; scarce respawns increase stakes | Document PlayStyle, LosMode, friendly fire, disguises, rewiring, karma, and voting rules |
These are starting profiles, not mandatory values. The documented fields give you control; your group decides how forgiving or restrictive the resulting game should feel.
Where are Barotrauma server settings stored?
The main file is serversettings.xml. It stores server name, password, description, game mode, ports, player limits, bots, respawn behavior, voting, karma, logging, mod downloads, voice chat, and mission selection for both dedicated and client-hosted servers.
The configuration index also lists separate files for other administrative data:
bannedplayers.txtfor bans.clientpermissions.xmlfor client permission assignments.karmasettings.xmlfor karma configuration.permissionpresets.xmlfor reusable permission sets.
When a lobby checkbox and the XML file appear to disagree, inspect the generated file and the actual server version before troubleshooting gameplay. Keep a backup of the files before editing, and make changes while the server is stopped so the running process cannot overwrite them.
Which game mode is best for my group?
The documented game-mode identifiers are sandbox, mission, campaign, and PvP. Pick the mode based on session length and persistence rather than on difficulty alone.
Campaign
Campaign is the natural default for a regular group. Travel, purchases, upgrades, and consequences carry between missions, so the crew can learn the submarine and develop a shared operating routine. It benefits most from a clear respawn policy and a difficulty preset that leaves room for recovery.
Sandbox
Sandbox is suited to testing a submarine layout, practicing a job, or experimenting with systems without committing the group to a continuing route. It is useful when players are learning controls or when you need to reproduce a technical problem.
Mission mode
Mission mode fits shorter, independent sessions. Mission-type fields can restrict or randomize the missions offered, allowing an organizer to keep a night focused instead of asking everyone to commit to a campaign.
PvP
PvP requires an explicit agreement about teams, friendly fire, disguises, and victory expectations. Set those rules before launch and put them in the server description; otherwise a setting that is funny in a test round can look like sabotage in a public lobby.
How should I set MaxPlayers, BotCount, and BotSpawnMode?
Set MaxPlayers to the number of human players your submarine and voice channel can support. Leaving many unused slots open does not improve a private session and makes it harder to communicate the intended crew size.
Small crews
For two to four friends, use one slot per expected human. Keep BotCount=0 when the point is to coordinate with friends. Add only enough bots to cover a role that would otherwise make the submarine impractical; extra automation can remove the need for players to learn that station.
Drop-in crews
If people join and leave throughout the evening, size the server for the normal peak rather than the theoretical maximum. BotSpawnMode=Fill is the documented option for filling empty slots with bots. Decide whether bots should disappear when a person arrives, and state that expectation in the server message so a joining player understands the arrangement.
Why capacity and bots affect difficulty
A four-player crew with no bots has fewer hands for repairs, loading, navigation, and weapons than a full roster. Increasing enemy difficulty while also reducing human capacity can create a much steeper challenge than the preset name suggests. Adjust one axis at a time so you can tell whether a failure came from hostile settings or from a missing role.
How do respawn and recovery settings work together?
Five documented controls shape recovery: AllowRespawn, UseRespawnShuttle, RespawnInterval, MaxTransportTime, and MinRespawnRatio. Together they determine whether a dead player returns, how long the return takes, whether a shuttle must dock, and what minimum conditions are required for the process.
Friendly campaign baseline
Turn on AllowRespawn and UseRespawnShuttle for a first campaign with friends. This preserves continuity when someone dies during a learning mistake or loses a connection at a bad moment. Choose an interval and transport time that fit your session length; a return that consumes most of a short evening is effectively a temporary kick.
High-stakes baseline
For an experienced group that wants consequences, keep respawn available but make recovery slower, or disable the shuttle only after everyone understands the result. Removing several recovery aids at once can turn a single accident into an unrecoverable campaign state, so change one control between test sessions.
What to explain before launch
- Whether a dead player waits for a timer or must travel in a shuttle.
- Whether a minimum living-player ratio can block a respawn.
- Whether the group pauses to retrieve a shuttle or continues without the missing player.
The settings provide the mechanics; the server description and voice briefing provide the social contract.
How should I tune campaign difficulty instead of just choosing Easy or Hard?
The official campaign page documents four presets: Easy, Normal, Hard, and Abyssal. Treat a preset as a baseline, then adjust individual resources and hazards to target the specific part of the game your group finds too forgiving or too punishing.
| Preset | Documented direction | Best use |
|---|---|---|
| Easy | More starting supplies and balance; Jovian radiation is turned off | New crews, teaching sessions, or groups prioritizing uninterrupted campaign progress |
| Normal | Middle baseline for resource and hazard settings | Mixed-experience groups that want the standard progression |
| Hard | Lower starting resources; higher shop and shipyard prices; greater world hostility; lower oxygen-tank and reactor-fuel multipliers; more damage from repair failures | Experienced crews that want economic and operational pressure |
| Abyssal | Pushes the constraints further, including lower reward multipliers and harsher hazard multipliers | Groups deliberately seeking a severe survival challenge |
Starting balance and hostility values
The official page lists starting-balance options of Low 6,000 mk, Medium 8,500 mk, and High 10,000 mk. These are configuration values, not measurements of what ordinary groups earn during play. World-hostility difficulty multipliers are listed as 60% for Easy, 100% for Medium, 160% for Hard, and 1,000% for the secret Hellish setting.
Use targeted adjustments
If the crew enjoys combat but runs out of money, keep the hostility setting and raise the starting balance or reward-related controls instead of switching to Easy. If repairs are the problem, reduce repair-failure consequences without also increasing supplies. If radiation creates a pacing issue, address that hazard directly. Separating resource, economy, and hazard axes makes the campaign readable: players know which behavior the server is trying to change.
Which moderation and privacy settings should a private server use?
Use a password for a private group and set the server description before inviting people. The description should state the game mode, expected voice behavior, mod policy, and whether bots or role-play rules are in effect.
Voting and AFK controls
AllowVoteKick and AllowEndVoting should match the group’s norms. In a trusted private crew, disabling votes can prevent a prank from ending a round; in a larger drop-in server, votes provide a transparent way to remove a disruptive or permanently idle player. Set KickAFKTime only after deciding how long someone may remain logged in while dealing with a real-world interruption.
Karma and logs
KarmaEnabled and KarmaPreset control whether the server applies automated behavior consequences. Karma can help on a public or semi-public server, but a small group may prefer direct moderation so an accidental discharge is discussed rather than scored. Enable logging and retain logs when you need to review an incident or distinguish a rule violation from a technical failure.
Voice, transfers, and downloads
Set voice-chat behavior and review AllowModDownloads and AllowFileTransfers according to your trust model. Automatic downloads are convenient for a closed group using a known mod list; stricter settings are safer when unknown players can join. Tell players how to obtain required content when automatic transfers are disabled.
How do I run a dedicated server and configure its ports?
DedicatedServer.exe is a command-line application with no graphical interface. The official hosting guide notes that it has less impact on the host computer than running the full game as a host. SteamCMD is also documented as an installation route.
- Install the dedicated server files, either through the documented game installation method or SteamCMD.
- Open
serversettings.xmland set the server name, password, game mode, capacity, and other options before launching. - Read the two UDP port values in that file. The documented defaults are player connections on
27015and the query port on27016. - Forward both UDP ports on the router to the computer running the server. Do not assume the defaults are still active if you or a previous installation changed them.
- Launch the executable from the command line and test discovery and joining from a second network or a friend’s connection.
Port forwarding is separate from the in-game player limit. A server can have a correct MaxPlayers value and still be unreachable if the forwarded ports do not match the values in the file or a firewall blocks the executable.
How should I handle mods and file transfers?
Decide whether the server is the source of truth for the mod list. A private, trusted group can enable AllowModDownloads and AllowFileTransfers to reduce setup work for new players. A public server should state exactly what is required and consider disabling automatic transfers if you do not want unknown files delivered to clients.
Keep the mod policy in the server description and avoid changing the list between missions without warning. When troubleshooting, first reproduce the problem with the documented configuration and no optional mods; otherwise a missing dependency can look like a networking or gameplay setting error.
Which settings matter most for competitive or role-play groups?
For these groups, consistency matters more than a universally “fair” value. Choose and document PlayStyle, LosMode, enemy-health-bar visibility, friendly-fire behavior, disguises, rewiring, karma, and voting before the first round.
Competitive play
Publish the rules for friendly fire, team identification, permitted rewiring, and round-ending votes. Keep the same values for an entire match series so teams are not adapting to hidden changes. If a setting changes the information available to players, such as health-bar visibility or disguises, treat it as a rules change and announce it.
Role-play play
Use the server description to define whether rewiring, disguises, or deliberate sabotage are in character. Karma and vote-kick settings should support the agreed fiction rather than punish ordinary role-play. A short written code of conduct prevents arguments that the XML settings cannot resolve.
What should I check after a Barotrauma update?
The official pages consulted list version 1.13.4.0, but both the serversettings.xml reference and dedicated-server guide carry freshness caveats. After an update, verify the fields most likely to affect connectivity and progression instead of assuming old defaults remain valid.
- Confirm both UDP port values and router forwarding.
- Check that the game-mode identifier and mission-selection fields still match the current build.
- Recheck respawn, shuttle, and minimum-ratio behavior with a short test session.
- Verify that lobby-exposed options still write the values you expect to
serversettings.xml. - Review mod-download and file-transfer permissions before inviting outside players.
- Keep the previous configuration and logs so you can restore a known-good setup.
How do I troubleshoot a server that is not behaving as expected?
Friends cannot find or join it
Compare the live serversettings.xml port values with the router’s two UDP forwarding rules, then check the host firewall. Test from outside the host’s local network; a local connection can succeed even when internet forwarding is wrong.
The submarine feels understaffed
Check MaxPlayers, BotCount, and BotSpawnMode. A low human cap or a fill mode that is disabled can leave essential stations empty. Raise capacity only to the level your group can coordinate, rather than adding unused slots.
Deaths remove players for too long
Review AllowRespawn, UseRespawnShuttle, RespawnInterval, MaxTransportTime, and MinRespawnRatio together. Changing only the interval will not help if a shuttle is disabled or the minimum ratio blocks the return.
The campaign is either trivial or impossible
Record which axis is causing the problem: starting supplies, shop and shipyard prices, hostility, oxygen-tank or reactor-fuel multipliers, reward multipliers, or repair-failure damage. Adjust that axis and leave the others unchanged for the next session so the result is measurable.
A player is disrupting the session
Use the server password, AllowVoteKick, KickAFKTime, karma controls, and logs as a coordinated moderation plan. Do not enable every automated penalty by default; choose the mechanism that fits the trust level of the group.
Frequently Asked Questions
Which files contain bans and permission presets?
The configuration index lists bannedplayers.txt, clientpermissions.xml, karmasettings.xml, and permissionpresets.xml separately from serversettings.xml. Backing up these files preserves administrative rules when you move or rebuild a server.
Can a dedicated server run without the game’s graphical interface?
Yes. The documented DedicatedServer.exe is a command-line application with no graphical interface. The hosting guide says this approach has less impact on the host computer than hosting through the full game.
Why does a setting appear in the reference but not in my lobby?
Not every documented field needs to be exposed as a lobby control. Check serversettings.xml directly, compare its field names with the current game build, and remember that the reference pages carry version-freshness caveats.
Do I need to forward both Barotrauma ports?
The official hosting instructions say to forward both UDP ports listed in serversettings.xml. The documented defaults are 27015 for player connections and 27016 for queries, but your file may contain different values.