Arma 3

The Steam account requirement, mod folders, missions and why milsim groups need memory.

Everything in Your panel applies. These are the Arma 3 specifics.

Steam credentials come first

Arma 3 server files can only be downloaded with a Steam account that owns Arma 3. Enter your Steam username and password in Startup parameters, then reinstall — the files download automatically and the server starts.

Without this the server has nothing to run. It is the first thing to check if a new Arma 3 server refuses to boot.

Startup parameters

• Steam User and Steam Password — for downloading the files
• Max Players and Server Password
• Startup Params — extra launch arguments
• Modifications — client-side mods players also need
• Server Mods — server-only mods
• Optional Mods
• CDLC — creator DLC

The split between Modifications and Server Mods matters. Anything that changes content goes in the first and must be loaded by players too; server-side-only additions go in the second and players never see them.

Installing mods

Mods come from the Steam Workshop or directly from authors. Upload the mod folders through the file manager or SFTP, then list them in the appropriate Startup parameters field.

Mod sets get large — hundreds of gigabytes for some collections — so keep an eye on your disk allowance as the list grows.

Everyone loads the same mod set for anything content-changing, or they cannot join. Most groups share a Workshop collection so the list is one click for players.

Missions

Mission files go into the server's mpmissions folder. The mission cycle and difficulty settings live in the configuration files, edited in the file manager — everything is plain text, so you can build a strict milsim profile or something more relaxed and switch between them.

Memory

Plans start at 4 GB, enough for a small group running standard missions.

Arma gets hungrier fast: more players, large unit and terrain mod packs, and persistent missions with a lot of AI and vehicles all push it up sharply. AI is the big one — a mission with hundreds of active units costs far more than the same mission with players only.

If your group runs modded operations regularly, plan for a higher tier from the start.