---
title: Modding your Arma 3 Nodecraft Server
description: Learn how to add Steam Workshop mods to your Nodecraft Arma 3 server with this guide.
source: "https://nodecraft.com/support/games/arma3/modding-your-arma-3-nodecraft-server"
image: "https://dynamic-assets.nodecraft.com/signedurl/w7vokBAexMnVlnMZ1Q/image.jpg?modifications=W3sibmFtZSI6ImdhbWVfYmciLCJpbWFnZV91cmwiOiJodHRwczovL2Ntcy1hLm5vZGVjcmFmdC5jb20vZi8xMzM5MzIvMjAwMHg1NTAvN2E3MTM0ODBlOC9hcm1hLTMtbGFuZGluZy1iYW5uZXItMS0yLTEucG5nL20vIn0seyJuYW1lIjoiZ2FtZV9sb2dvIiwiaW1hZ2VfdXJsIjoiaHR0cHM6Ly9jbXMtYS5ub2RlY3JhZnQuY29tL2YvMTMzOTMyLzM3NXgxNTAvYzc1ZDIxZWY1OS9sb2dvLnBuZy9tLyJ9LHsibmFtZSI6ImN0YV90ZXh0IiwidGV4dCI6IkNyZWF0ZSB5b3VyIG93biBzZXJ2ZXIhIn0seyJuYW1lIjoidGV4dCIsInRleHQiOiJNb2RkaW5nIHlvdXIgQXJtYSAzIE5vZGVjcmFmdCBTZXJ2ZXIifV0&s=3882b9f21faeeb43398125449b0516897e9803b1a2d4000e369c88bbfbfda481"
published: "2023-12-13T00:21:44.334Z"
updated: "2023-12-12T23:37:00.000Z"
---

# Modding your Arma 3 Nodecraft Server

Learn how to add Steam Workshop mods to your Nodecraft Arma 3 server with this guide.

Arma 3’s Steam Workshop offers hundreds of mods for players to enjoy. This article will cover uploading your mod files to the Nodecraft server and installing them on your Arma 3 server instance.

## Downloading and Uploading Mods to the Server

Before installing anything you will need to grab the mod files from your PC client and upload them to the server. If you have not done so already, select which mods you like and Subscribe to them in your [Arma 3 Steam Workshop](https://steamcommunity.com/app/107410/workshop). You will begin downloading mod files for each item you Subscribe too, so don’t forget any dependency mods.

For the purposes of this article we will be showing how to install the mod [OPTRE](https://steamcommunity.com/sharedfiles/filedetails/?id=769440155).

![Arma 3 Launcher with OPTRE mod installed highlighting where to locate mod files](https://cms-a.nodecraft.com/f/133932/954x677/8112220a64/arma3_launcher_mods.png/m/)Once you’ve downloaded all of your mods select one of your mods in the launcher and click the `...`. This will open the Arma 3 Steam folder where your mod files are. Otherwise you can manually go to that hidden folder at `\Steam\steamapps\common\Arma 3\!Workshop`.

Each of your mod folders will typically begin with the `@` symbol and will match the mod’s name.

![Arma 3's Steam Workshop mods location and example](https://cms-a.nodecraft.com/f/133932/2000x542/9020e64f1b/arma3_clientside_mods_example.png/m/1000x0/smart)We recommend zipping your files with a tool such as [7Zip](https://www.7-zip.org). Once finished you can drag and drop the zip file into your File Manager. If the file is too large or you are experiencing issues with uploading, check out our article on [uploading files with FTP.](https://nodecraft.com/support/knowledgebase/nodepanel/basic-ftp-tutorial)

Once that has completed unzip your mods in the main directory.

![Arma 3 Nodepanel Filemanager with unzipped mod folders with incorrect filenames](https://cms-a.nodecraft.com/f/133932/2000x1945/019b784730/arma3_filemanager_unzipped_mods.png/m/1000x0/smart)

## Installing and Enabling Your Mods

Now that the files are on the server it should be simple to enable them right? Unfortunately not, Arma 3 requires a few extra steps. More on that in a moment. Before that, a quick note on some important files you should locate.

### The .pbo, .bisign, and .bikey Mod Files

Arma 3 mod folders contain many files, but there are three essential types for mods to run properly on both the client and server. The `Addon.pbo` files are your main mod files. The `Addon.MyBikey.bisign` files is the mod author’s signature which indicates the `Addon.pbo`  has not been modified by anyone but the author. The `MyBikey.Bikey` file is used by the server to validate with a mod’s `Addon.MyBikey.bisign` file.

These files will typically be contained within the addons and keys folder.

![Arma 3 Nodepanel Filemanager highlighting the Steam Workshop mod's addons and Keys folders](https://cms-a.nodecraft.com/f/133932/2000x917/d1835bfdd3/arma3_mod_addonsandkeys_folders.png/m/1000x0/smart)

### Moving the Signature .bikey File for Verification

In order for Arma 3 to verify that the server and client mod keys/signature are matching, they must be copied to a different folder. Locate and select each of your mod’s `.bikey` files and place a copy in the `/keys` folder.

![Arma 3 Nodepanel Filemanager keys folder with example .bikey files](https://cms-a.nodecraft.com/f/133932/2000x642/1b8367486c/arma3_mod_keys_example.png/m/1000x0/smart)As a note, some mods may not contain the `MyBikey.Bikey` or  `Addon.MyBikey.bisign` files. This indicates that the mod is server side and does not need to signal the client, meaning this step can be skipped.

### Adjusting File Names

Since Nodecraft servers operate on a Linux OS, syntax for Arma 3 files becomes much more important. The names of each of your mod’s folder need to remove capitalization, spaces, and special characters (except underscores) in order to load properly. For example `@Operation TREBUCHET` and `@CBA_A3` would change to `@operation_trebuchet` and `@cba_a3`.

These syntax restrictions are also needed for the mods `.pbo` files in the addons folder.

![Arma 3 Nodepanel Filemanager with incorrect filenames within the mod's addons folder](https://cms-a.nodecraft.com/f/133932/2000x1268/1ab25e4675/adjust_arma3_filenames_part1.png/m/1000x0/smart)![Arma 3 Nodepanel Filemanager custom mod's addons folder with adjusted correct filenames](https://cms-a.nodecraft.com/f/133932/2000x1415/ad8a102fa4/adjust_arma3_filenames_part2.png/m/1000x0/smart)While this can be an admittedly ridiculous and **tedious** process, it is needed for these mods to load properly. The server console should also direct you towards files that have any syntax issues after enabling your mods on the command line.

Luckily, we have a tool to make this a little easier on you. On the Game Settings page, click the `Fix Mods folder` button. This should save you the tedium of manually correcting each and every one by doing them all automatically.

![Nodepanel's Game Settings Fix Mods folder button location](https://cms-a.nodecraft.com/f/133932/907x647/1e4e3db96e/arma3_nodepanel_modsfix.png/m/)![Arma 3 Nodpanel Filemanager highlighting the mod filenames that have been fixed](https://cms-a.nodecraft.com/f/133932/2000x696/0258bc7bce/arma3_foldername_mods_fixed.png/m/1000x0/smart)

### Enabling Mods On the Command Line

Returning to the Game Settings page, all Custom Server Arguments or Startup Arguments can be added here. To enable mods, there are two startup arguments available.

`-mod=mod1\;mod2\;mod3` will work in most cases where mod1, mod2, etc. are the names of the mod folders you changed earlier. For example to enable the two mods we’ve added it would need `-mod=@cba_a3;@operationt_trebuchet`

![Arma 3 Startup Arguments example in Game Settings](https://cms-a.nodecraft.com/f/133932/2000x1410/5b151e449d/arma3_mod_startup_args.png/m/1000x0/smart)`-servermod=mod1\;mod2\;mod3`  can also be used, but is specifically for mods that do not have a `.bikey` file as mentioned earlier.  Many mods will work with both `-mod` and `-servermod`.

### Final Touches in the server.cfg

Finally, before starting up the server, you’ll need to create a `server.cfg`. As mentioned in our guide [Configuring Your Arma 3 Nodecraft Server,](https://nodecraft.com/support/games/arma3/configuring-your-arma-3-nodecraft-server) the config security line `verifySignatures = 2;` enables the verification process for your mods.

If all steps were followed correctly, the server should start up with your mods! Otherwise, we recommend checking your server console for any errors. If you continue to have issues, try contacting our [Support team](https://nodecraft.com/support) for assistance.

## Additional Tips

1. Many mods require modded scenarios/missions in order to use the modded content. We recommend our article [Adding Missions to your Arma 3 Server](https://nodecraft.com/support/games/arma3/adding-missions-to-your-arma-3-server) for further steps.
2. Sub-folders can be used to organize mods if properly setup. For example if all of the “@” modded folders are placed into one `mods` folder then you can enable those mods by specifying them on the command line with `-mod=mods/@cba_a3;mods/@operation_trebuchet`

  ![Arma 3 Nodpanel Filemanager showing modded @ folders in a sub-folder](https://cms-a.nodecraft.com/f/133932/2000x606/5613749932/arma3_mods_subfolder.png/m/1000x0/smart)
