A headless Client is used to offload AI calculations from the server.
Headless Client is integrated into the game client and dedicated server executable (Windows and Linux, use -client parameter).
The server does not allow arbitrary connections from headless clients if you do not define the headless clients' IPs in the server.cfg.
Headless Client Setup and Usage
Starting up a headless client and having it connect to your server is easy, Creating a mission that uses the Headless Client is not.
This guide only handles the setup and connecting a headless client.
Create a new server instance using LinuxGSM ./linuxgsm.sh arma3server. This will become the headless client instance and rename the new instance to arma3server-hc.
Edit the config file lgsm/config-lgsm/arma3server-hc.cfg.
Change the port= increasing the number by a factor of 12 e.g 2303 becomes 2314.
Update startparameters= changing it to the following.
Edit the game server config of arma3server (not the headless client) arma3server.server.cfg and add the headless client IP address to headlessClients[]=. If the headless client is on the same physical server as the ARMA 3 server then also add the IP to localClient[]=.
edit Player.Arma3Profile and add the line battleyeLicense=1;.
Start your server with ./arma3server start
Start your headless client with ./arma3server-hc start.
Only an admin can see the headless clients in the player menu on the server. The headless client will connect and automatically assume the first available headless client slot.
Mod Support
Arma 3 mods are managed using the Steam Workshop or manual downloads.
Adding Mods
Firstly, you need to select the mods you want to use from the steam workshop.
Mods can cause your server to become unstable or may not be compatible with each other. It is a good idea to read the mods docs and/or speak with other experienced Arma3 admins.