Terraria serverconfig.txt Explained: Every Key, Grouped by What It Does

The whole configuration of a Terraria dedicated server is one file of key=value lines, read once at start. It is short enough to learn in full, and learning it in full is worth it, because three of its keys only do anything the first time a world is created, one of them silently decides which world you are playing, and fifteen of them only matter in Journey Mode. This is every key, grouped by what it does, with the command-line flags that duplicate them.

Keys and ranges are from the config file that ships inside the official 1.4.5.8 server zip and the Terraria wiki's server page.

Where the file is

The server reads the file you name with -config:

./TerrariaServer.bin.x86_64 -config serverconfig.txt

The example serverconfig.txt ships only in the Windows/ folder of the zip, so Linux users copy it across or write their own. On a Connect Terraria server the file is written for you from the Server Settings tab on every start; the keys the tab manages are listed at the end.

The world keys

The point that trips people: autocreate, worldname, seed and difficulty are read only when a world is being created. Change difficulty for an existing world and nothing happens. And world is not a label — point it at a path with no file and the server generates a fresh world there, which looks like your old one vanishing. The old file is still where it was.

The special seeds each have a key too: seed_celebration, seed_theconstant, seed_notthebees, seed_notraps, seed_fortheworthy, seed_remix, seed_drunk and seed_zenith. They apply at creation like seed does.

The player keys

maxplayers is the number people argue about. The game accepts anything from 1 to 255; the wiki quotes a default of 16 and the shipped example says 8; Re-Logic recommends nothing. Any cap a host advertises — sixteen on every Connect plan, for instance — is that host's choice, not a limit of the game.

The network keys

The process keys

The Journey Mode keys

Fifteen keys, all journeypermission_<power>, each set to 0 (locked), 1 (host only) or 2 (everyone, the default). They only matter on a world created with difficulty=3:

journeypermission_time_setfrozen=2
journeypermission_time_setdawn=2
journeypermission_time_setnoon=2
journeypermission_time_setdusk=2
journeypermission_time_setmidnight=2
journeypermission_godmode=2
journeypermission_wind_setstrength=2
journeypermission_rain_setstrength=2
journeypermission_time_setspeed=2
journeypermission_rain_setfrozen=2
journeypermission_wind_setfrozen=2
journeypermission_increaseplacementrange=2
journeypermission_setdifficulty=2
journeypermission_biomespread_setfrozen=2
journeypermission_setspawnrate=2

Which ones to lock on a shared server, and why 1 means little on a dedicated server, is the subject of Journey Mode server permissions.

Config keys versus command-line flags

Most keys have a flag twin: -port, -players (or -maxplayers), -pass (or -password), -motd, -world, -autocreate, -worldname, -seed, -banlist, -secure, -noupnp, -ip, -forcepriority, -disableannouncementbox and -announcementboxrange. Two flags have no config equivalent and are not for a dedicated server at all: -steam and -lobby friends|private create a Steam-friends session, which has nothing to do with joining by IP. Flags for difficulty, worldpath and language are not documented; use the file for those.

A file is easier to keep straight than a long command line, and it is what every hosting panel writes, so our advice is to put everything in serverconfig.txt and pass only -config.

A complete example

world=/home/you/terraria/worlds/Dirt Castle.wld
autocreate=2
worldname=Dirt Castle
seed=
difficulty=0
maxplayers=8
port=7777
password=changeme1
motd=Welcome to Dirt Castle
worldpath=/home/you/terraria/worlds
worldrollbackstokeep=2
secure=1
language=en-US
upnp=0
npcstream=60
priority=1

Change world, worldname, worldpath and password, pick a size and difficulty, and that is a working server. The install around it is in the setup guide.

What the console changes, and what it does not

A few values can be changed while the server runs, from the console: password, motd and maxplayers are also console commands (the first two set, the third only prints). Those changes last until the next start, when the file is read again. Everything else is file-only and needs a restart. Shutting down with exit saves the world; exit-nosave does not.

On a Connect server

The Server Settings tab manages world, autocreate, worldname, seed, difficulty, maxplayers, password, motd and language, and writes port, worldpath, worldrollbackstokeep=2, secure=1, upnp=0, npcstream and priority=1 for you. The tab also warns when a change to World Name would create a new world — the trap from the first table. Keys the tab does not manage, such as the Journey permissions, can be added on the Files tab and are left in place across restarts. Every setting on the tab is described in server settings.

Frequently Asked Questions

Where is serverconfig.txt?

Wherever you put it: the server reads the file named by -config. The example ships in the Windows/ folder of the official zip.

Why did changing difficulty do nothing?

difficulty, like autocreate, worldname and seed, applies only when the server creates a world. An existing world keeps the difficulty it was made with.

What is the maximum maxplayers?

255. The minimum is 1. The shipped example uses 8; the wiki quotes 16 as a default. Re-Logic recommends no figure.

Does the server need UDP open?

No. Joining by IP uses TCP on the port set by port, 7777 by default.

What does worldrollbackstokeep do?

It sets how many previous saves are kept as .wld.bak files beside the world, so a bad save can be rolled back. The shipped example keeps 2.

Can I change settings without restarting?

password and motd can be set from the console while the server runs, until the next start. Everything else is read from the file at start.