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How to run a dedicated server

foofski edited this page Feb 9, 2017 · 18 revisions

Please Note: This guide assumes at least a basic knowledge in running Arma 3 dedicated servers. Please refer to the Arma 3 documentation at for more information.


With your dedicated server already setup (with APEX) and running a vanilla installation, you simply need to copy the following folders from your Arma 3 root folder (or "!Workshop" folder within that root):

  • @CBA_A3
  • @ace
  • @Overthrow

Copy these folders as is to your server's root folder.


You DO NOT need anything in your mpmissions folder, all Overthrow missions are included with the mod, simply use the mission voting screen.

Server keys

Copy the key signatures to your server's "Keys" folder as you would for any other mod. Each of those 3 folders contains a "keys" folder, copy all of the ".bikey" files from them to your server's own "/Keys" folder so it looks something like this:

(Note that your version numbers may be different.. just ensure that you are always using the latest versions)

Command Line

You need to load all 3 mods under the "-mod" commandline parameter in this order:


Recommended Difficulty Settings (Custom)

Put the following in username.Arma3Profile (ie /A3DS/Profiles/Users/SYSTEM/SYSTEM.Arma3Profile). Choose "Custom" difficulty when voting for the mission.

class DifficultyPresets
	class CustomDifficulty
		class Options


You need to ensure your server is always up to date with the latest versions or players that have already updated via steam will be kicked off. Make sure to repeat the "server keys" step above, and clear out older .bikey files as you do.

Headless clients

A headless client is another copy of the game running on a separate computer to reduce AI load on a server and regain FPS on both the server and all connected clients. Overthrow supports up to 4 headless clients but feel free to add more if you know how. Headless clients do not need a GPU, just a decent CPU (hence the term 'headless').

To run a headless client on Windows you need another licensed copy of Arma 3 + APEX. Then copy the 3 required mods into your Arma 3 root folder and put the following in a .bat file (changing parameters as required).

cd /D "C:\Program Files (x86)\Steam\steamapps\common\Arma 3"
"C:\Program Files (x86)\Steam\steamapps\common\Arma 3\arma3server.exe" -client -connect= -port=2502 -mod=@CBA_A3;@ace;@Overthrow;

Double click the .bat file and it should connect to your server as "headlessclient" and begin taking load when you next spawn in any units.

Please note: Recruited units/squads currently remain local to their owner. This can cause undue load on your system if you have a lot of them (even when running a headless client). This will be revisited but be aware for now.


What happens when no one is online?

Time will still pass at the same rate. NATO will not begin any attacks. Criminal gangs will not be created but existing ones will remain. Radio towers and police stations will still affect stability at the normal rate.

What happens when I disconnect/reconnect (or crash)

Your recruited AI will remain doing whatever it was they were doing, you will regain control of them when you reconnect. The loadout you had at disconnection will be re-applied on connection. Your money, owned buildings and all character progress etc will all be retained per server.

##Why can't I vote for the Overthrow mission once I start my ARMA client You may need to set these parameters in your server.cfg: voteMissionPlayers = 1; voteThreshold = 0.33;

How do I load my persistent save?

Restart your server and select the mission again (or use the #restart admin command) then choose "Load Persistent Save".

Why does persistent save take so long on a dedicated server?

We wish we knew

Why is it a mod and not just a mission?

There are items modded in and will be much more as time goes on, as well as new maps etc. We understand that regular updates can be taxing on a person running a dedicated server and a mission would make this easier, however the scope of this mod will expand rapidly and updates will slow down as we approach 1.0.0

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