How to set up an Arma Reforger dedicated server
By Benjamin D. · PDG
· 2 min read
Contents
Arma Reforger runs on the Enfusion engine, and its dedicated server is configured entirely through a JSON file. That is stricter than a plain properties file — one misplaced comma and the server refuses to start — but it is also far more explicit about what is actually running.
What you need
- SteamCMD, which pulls the server application. It is separate from the game and installs with an anonymous login.
- UDP ports open: the game port and the query port. Opening only the first gives you a server that runs perfectly and appears nowhere.
- A machine with good single-core clock speed. Enfusion leans hard on the CPU during large engagements.
- Network headroom. A populated Arma Reforger server uses noticeably more bandwidth than most survival games.
The configuration file
Everything lives in a JSON file you write yourself: server name, loaded scenario, slot count, mods, gameplay settings. Unlike most games, it is not generated on first launch. You supply it, and the server will not start without it.
That feels awkward at first, and it is also what makes the setup reproducible: one file, one configuration, no hidden state anywhere else on disk.
The mistakes that keep coming back
- Malformed JSON. One extra comma and the server exits at startup. The message is clear but scrolls past quickly.
- Only one port open. The server runs, logs look clean, and nobody can find it in the browser.
- A mistyped scenario reference. The server starts on something other than what you intended, with no error at all.
- Mods declared with the wrong ID. They are silently skipped.
Confirming it worked
The startup logs state the scenario that was loaded, the slot count, and the port actually being listened on. That is the only reliable source: if what you read there does not match your JSON, the file being loaded is not the one you edited.
If you would rather skip that step entirely, our Arma Reforger server hosting ships a working instance with the JSON still accessible for whatever you want to change afterwards.
