How to Add Workshop Addons to a Garry's Mod Server

Workshop collections are the easiest way to run addons on a Garry's Mod server. Instead of uploading files by hand, you point the server at one collection and it downloads everything on startup.

Create the collection

1. Subscribe to nothing on your own account; instead open the Steam Workshop for Garry's Mod and click Collections, then Create.
2. Add every addon, map and content pack you want, then set the collection visibility to Public or Unlisted so the server can read it.
3. Copy the numeric ID from the end of the collection URL.

Point the server at it

Garry's Mod uses a launch parameter for this. Add the following to your startup command, replacing the number with your collection ID:

• +host_workshop_collection 123456789

Depending on your setup you may also need a Steam Web API key passed with -authkey. If Workshop items fail to download, check that this is set. Ask us on Discord if you are not sure where the startup command lives in your panel.

Apply the change

1. Stop the server from the Console tab.
2. Update the startup variables or command in your panel.
3. Start the server and watch the Console for Workshop download lines.

The first start after adding a large collection can take a while, so be patient before assuming it is stuck.

Make clients download content

Collections are mounted on the server, but players only get the files if you tell them to. In a Lua file under garrysmod/lua/autorun/server/ you can call resource.AddWorkshop with the Workshop item ID for each addon that has models, materials or sounds. Without this, players may see missing textures or purple-and-black ERROR models.

Tips

• Keep collections small. Every addon adds load time and potential conflicts.
• Remove addons one at a time when debugging errors, rather than guessing.
• Maps from the Workshop must also be in the collection if you want to switch to them.
• After the Workshop updates an addon, restart the server to pull the new version.