Creating a "server.cfg" file for your Arma 3 Server
Arma 3 does not provide a server.cfg by default. If you want to change the configuration of your Arma 3 server, you will need to create a file manually, and then set a startup parameter on the server control panel to load that file on startup.
Naming the configuration file
First off, you don't need to name the file server.cfg. The name of the file can literally be anything.
Since you tell the game exactly which file to look for and load using a startup parameter for the game, you can actually name the config file whatever you want. This allows you to have more then one config file, and quickly switch between them simply by changing the parameter on each startup. You can have a config file tailored to a specific mission, a whole series of missions, configs for training missions, for serious gameplay, etc.
You should avoid spaces in the file name, so use things like underscores if you want multiple "words" for the file name:
for_example_like_this. What to put in the file
The best resource for the config file settings is also going to be the developer's site, Bohemia Interactive. They have a page on the config file, and examples of what can be included in it. The link is below.
https://community.bistudio.com/wiki/server.cfg
If you want to include comments in the config file, put double slashes at the start of the line (//) and everything past the double slashes will be skipped by the game. Leaving notes is always a good thing, in case you forget why a specific setting is in the file. You could also use the comments to list specific missions the config file is intended to be used with, and other things.
Activating the Config File
Once a server file has been created on the server (or uploaded), the next step is to direct the server to actually use the file, and that is done by using a startup parameter.
You can enter startup parameters by clicking on the "Game Settings" tab of the Nodecraft Arma 3 server control panel. You will see a white box labelled "Params:"
In the box, enter the command:
-config=(filename)
Be sure to replace (filename) with the name of your file, such as -config=server.cfg.
Then click the "Save" button. If you have more than one startup parameter, each should be added to it's own "params" box. Click the plus sign in a circle at the right end of the box to add more boxes for parameters.
