How to Install Mods on Your Arma 3 Server

In Arma 3, mods are folders in the main directory of your server and always start with an @ – for example @cba_a3. They are loaded through two start parameters that you set through the corresponding fields in the dashboard.

In both cases you separate multiple mods with a semicolon:

@cba_a3;@ace;@operation_trebuchet

Method 1: Export a mod list from the launcher

With this method your server downloads the mods from the Steam Workshop itself. It is the easiest way for Workshop mods.

1. Start the Arma 3 launcher
   Start Arma 3 via Steam so the launcher opens and switch to the Mods tab.

2. Enable the mods
   Enable all mods that should run on your server. Make sure required dependencies such as @CBA_A3 are enabled too.

3. Export the mod list
   Export the active mod list as an HTML file to your PC using the launcher's preset function.

4. Stop the server
   Stop your server via the dashboard.

5. Upload the file
   Connect to your server via SFTP and upload the file as modlist.html into the main directory:

   /modlist.html
   

6. Enter the mod list
   Open the settings in your dashboard and enter the file name in the field for the mod list file. By default it already says modlist.html.

7. Start the server
   Start your server. The mods from the list are downloaded on startup – depending on their size this can take a few minutes.

Method 2: Enter Workshop IDs directly

Instead of a mod list you can also specify mods individually by their Workshop ID.

1. Copy the Workshop ID
   Open the mod page in the Steam Workshop. The ID is the number at the end of the address, for example 450814997 in .../filedetails/?id=450814997.

2. Stop the server
   Stop your server via the dashboard.

3. Enter the IDs
   Enter the IDs in the settings in the field for the mods – each with a leading @ and separated by semicolons:

   @450814997;@463939057;
   

   Server mods go into the field for server mods instead.

4. Start the server
   Start your server. The mods are downloaded on startup.

Method 3: Upload mods manually

You need this method for mods that do not come from the Workshop.

1. Subscribe to the mod
   Subscribe to the mod in the Steam Workshop and start Arma 3 once so it gets downloaded.

2. Open the mod folder
   You find the subscribed mods on your PC under:

   ...\Steam\steamapps\common\Arma 3\!Workshop
   

3. Rename the folder
   Rename the mod folder to all lowercase and replace spaces with underscores, for example @operation_trebuchet. Also rename the .pbo files in the addons subfolder to lowercase.

4. Pack the folder
   Pack the mod folder into a .zip file.

5. Stop the server
   Stop your server via the dashboard.

6. Upload and extract
   Connect via SFTP, upload the archive into the main directory of your server and extract it there. Afterwards the mod folder has to sit directly in the main directory:

   /@operation_trebuchet
   

7. Copy the key
   Open the keys (or key) subfolder of the mod and upload the .bikey file it contains into the /keys folder of your server.

8. Enable the mod
   Enter the folder name in the settings in the field for the mods – separate multiple entries with semicolons:

   @cba_a3;@operation_trebuchet
   

9. Start the server
   Start your server.

Verify signatures

To make sure only players with unmodified mod files can join your server, Arma 3 verifies the signatures of the mods. For this, the .bikey of every mod has to be in the /keys folder. In Arma 3 the verification is enabled by default – when in doubt, check whether the value is set in your server.cfg.

1. Stop the server
   Stop your server via the dashboard.

2. Open the server.cfg
   Open the file /server.cfg via SFTP.

3. Enable signature verification
   Enter the following value:

   verifySignatures = 2;
   

4. Start the server
   Save the file and start your server.

Troubleshooting