How to Add Mods to an Arma Reforger Server (Step by Step)

To add mods to an Arma Reforger server, you list each Workshop mod’s 16-character ID in the game.mods section of the server’s config.json and restart it. The server downloads the mods from Bohemia’s own Workshop by itself, with no account, and every player gets them when they join, on PC, Xbox or PS5.

The catch is that the server checks config.json against a strict format. One wrong character in a mod entry, like a version with four numbers, and it refuses the whole file and never starts. Our Arma Reforger config.json field guide explains the surrounding blocks and documented field types; this guide shows how to add mods: where the ID is, the exact entry to write, how to check the file, the log lines that prove each mod loaded, and the fixes for the errors that stop modded servers. Everything here was checked on game version 1.8.0.13.

Find each mod’s ID on the Workshop#

Every Arma Reforger mod has a modId: 16 hexadecimal characters (digits and the letters A to F) that never change between versions. The server only needs that ID; the name is a label for you.

Reforger mods live on Bohemia’s Workshop, not Steam’s, so Steam Workshop links and numbers don’t work here. You can read the ID in three places:

The Mod manager copy is the fastest route when your group already plays with a set of mods: enable them in your own game, copy the JSON and paste its entries into the server file. It also includes the mods each one depends on, which saves you from the most common mistake. If you’ll add many mods at once, exporting the full list from the game is worth learning on its own.

Two examples used through this guide, both checked on the Workshop on 3 October 2026:

• Overthrow by Aaron Static: ID 59B657D731E2A11D, version 1.5.2, about 60 MB.
• RHS - Status Quo by Red Hammer Studios: ID 595F2BF2F44836FB. It needs two other mods from the same authors, RHS - Content Pack 01 and RHS - Content Pack 02, which add up to about 8.5 GB.

Their authors made them; credit them the same way if you share your server’s mod list.

Add the mod to game.mods in config.json#

config.json holds the server’s whole setup. The mod list sits inside the game block as mods, an array with one object per mod. Stop the server, open the file and add the entries:

{
  "game": {
    "name": "Friday Op",
    "scenarioId": "{ECC61978EDCC2B5A}Missions/23_Campaign.conf",
    "maxPlayers": 32,
    "crossPlatform": true,
    "mods": [
      { "modId": "59B657D731E2A11D", "name": "Overthrow", "version": "1.5.2" },
      { "modId": "595F2BF2F44836FB", "name": "RHS - Status Quo" },
      { "modId": "1337C0DE5DABBEEF", "name": "RHS - Content Pack 01" },
      { "modId": "BADC0DEDABBEDA5E", "name": "RHS - Content Pack 02" }
    ]
  }
}

Your file has more keys than this; leave them as they are and only touch mods. The last two lines are the content packs RHS - Status Quo needs (IDs 1337C0DE5DABBEEF and BADC0DEDABBEDA5E); the Mod manager copy includes them for you.

What each field does:

The default for required comes from modsRequiredByDefault in the same game block, which is true unless you changed it. Leaving version out is the usual choice for a group that wants mods to follow their authors’ fixes; filling it in is how you hold a mod still while you test an update, which has its own trade-offs.

List every mod a mod depends on, as with the RHS content packs above. Dependencies and the order they go in have more nuance than fits here; the safe rule is that anything the Workshop page says is required belongs in your list too.

Check the JSON before you save#

Most broken modded servers come down to the text of config.json, not the mods. Check the file before you start the server, because the server’s own error message is less friendly than a JSON checker.

1. Check the structure

   Every entry is { ... }, entries are separated by commas, and the last one has no comma after it. The whole list sits between [ and ]. Keys and text values are in straight double quotes ("), never curly quotes from a word processor or a chat app.

2. Check the values

   Each modId has exactly 16 characters, digits and A to F, with no spaces. Each version, if present, has three numbers separated by dots. required is true or false without quotes.

3. Look for duplicates

   The same mod listed twice, even once in capitals and once in lowercase, is a mistake. Remove the extra line.

4. Run the file through a JSON validator

   Paste the whole file into any JSON validator or open it in an editor that checks JSON (VS Code underlines errors). It should report the file as valid with no errors. A validator doesn’t know Arma’s rules, so the version format from the previous step is still on you.

Restart and confirm the mods in console.log#

Start the server again with a full restart of the process: stop it and start it, or use your panel’s Restart button. The #restart admin command only restarts the scenario inside the running server, so it doesn’t read the new mod list.

On start, the server reads game.mods, asks Bohemia’s Workshop for each mod and downloads what it doesn’t have yet into the profile folder, under addons/, one folder per mod (<Name>_<ID>). Then it loads the scenario. Watch the console, or open the newest log at <profile>/logs/logs_<date>/console.log, and look for these lines in order:

The first start after adding a big pack takes longer. On a datacentre connection, the three RHS packs (8.8 GB) took about 6 minutes to download on our test server; Overthrow alone took seconds. Later starts skip mods that are already up to date, unless their author published a new version and you didn’t pin one.

If your scenario comes from a mod (Overthrow brings its own), set scenarioId to that mod’s scenario only after the mod has downloaded once, or the server can’t find it. To check the scenario is the one you chose, join and look at the mission name, or search the log for the .conf file you set.

Fix the errors that stop a modded server#

When the server stops after a mod change, the reason is near the end of console.log. These are the errors owners hit most:

Game updates are the other source of trouble. A mod can stop working until its author updates it, so check the item’s Workshop page when the game or server branch changes. As of 8 October 2026, Stable is 1.8.0.13 and Experimental 1.9.0.10 is a separate branch. Bohemia’s 1.9 modding notes describe changes that may affect existing mods, including wheeled-vehicle simulation; they do not say that all vehicle mods are broken. Check each affected mod instead of assuming a blanket failure.

Removing a mod from the list doesn’t delete its folder from addons/. A big pack you dropped can keep several gigabytes of disk; delete the <Name>_<ID> folders of mods you no longer use while the server is stopped.

If you’d rather not edit config.json by hand at all, Game Hosting’s Arma Reforger servers take a Workshop search, a link or the list the game’s Mod manager copies, add the mods each one requires, and refuse duplicates, four-number versions and IDs that aren’t public Workshop mods before anything is saved, so a typo can’t keep the server from starting.

Get your players in, including Xbox and PS5#

Players don’t install anything by hand. When they join, their game downloads the same mods the server lists, from the same Workshop. On PC that usually takes a few minutes for a normal list; the first join after you add a big pack takes longer, so tell your group before game night instead of during it.

Console players can join a modded server too, with three conditions:

• The server has "crossPlatform": true in the game block. It’s off unless you set it, and without it Xbox and PS5 players don’t see the server at all.
• Every mod supports consoles. Some mods are made for PC only, and one of them in the list keeps console players out. Check each mod’s Workshop page and description before adding it if your group plays on Xbox or PS5.
• The list fits. Bohemia documents a 25 GB PS5 mod limit; Xbox’s local pool can grow from 1 GB up to 50 GB depending on use. These are local-library limits, not a guarantee that every player has the full amount free. Check the Workshop item’s size and the player’s available space; download time depends on the player’s connection and isn’t a fixed rate.

Xbox and PS5 can’t run the dedicated server themselves, and neither can Xbox Play Anywhere on a laptop. The server runs on a PC, a Linux machine or a rented server, and console players join it from the in-game server browser. Mods have worked on PS5 since version 1.4 (May 2025).

Once everyone is in, a quick check confirms the mods loaded for them: the scenario starts as expected, and each mod’s content (Overthrow’s map markers, RHS’s weapons and vehicles) is where it should be. If a player is stuck on a download while everyone else is in, the problem is usually on their side, not the server’s.

For the broader model behind Workshop delivery, console compatibility and game-branch changes, see how Arma Reforger mods work on servers and consoles.