How to Make a Garry's Mod Server: Step-by-Step Guide

Step 1: Start a Free Trial

Go to the Zeros Host free trial page and select Garry's Mod. No credit card is required. You will be asked to choose a gamemode before the server starts: pick the one that matches what you want to run. The server is online within a minute and you land in the panel console.

Step 2: Choose Your Gamemode

Garry's Mod runs different gamemodes. Sandbox is the default: players build freely, no objective. DarkRP is a roleplay gamemode (jobs, economy, laws: see our DarkRP setup guide for the full walkthrough). TTT is a social deduction game for 8-20 players. Prophunt has props hiding as objects while hunters try to find them. If you selected the wrong gamemode at creation, change the gamemode line in server.cfg and restart.

Step 3: Create a Workshop Collection

Workshop addons are distributed via Steam Workshop. The standard way to manage them on a server is through a Workshop Collection. Go to the Steam Workshop for Garry's Mod, find addons you want, create a new Collection on your Steam profile, add each addon to the collection, make it Public, and note the collection ID from the URL (the number after ?id=).

Your collection ID links all the addons together so the server downloads them as a group. Players also auto-download the addons when they join.

Step 4: Link Your Collection to the Server

Add your Workshop collection to server.cfg. For client downloads so players get the addons on join, create a file at garrysmod/lua/autorun/server/workshop.lua with a resource.AddWorkshop line per addon.

# In server.cfg
+host_workshop_collection YOURCOLLECTIONID

# In garrysmod/lua/autorun/server/workshop.lua
resource.AddWorkshop("ADDONID")  -- one per addon

Save both files using the Browser IDE or file manager, then restart the server.

Step 5: Add a Map

By default the server runs on gm_construct. To change the map, set the map in server.cfg. If the map is a Workshop addon, add it to your collection so it downloads to the server. If using a default GMod map, just set the map name, no download needed.

# In server.cfg
map rp_downtown_v4c_v2

# Common maps
# gm_flatgrass, gm_construct     -- Sandbox classics
# rp_downtown_v4c_v2             -- popular DarkRP map
# ttt_rooftops_a2_f1             -- popular TTT map

Step 6: Install ULX Admin Mod

ULX (with its dependency ULib) is a widely used admin mod for Garry's Mod servers. Install via the Mod Manager in your panel: search "ULX" and install both ULX and ULib. Restart the server. In-game, open the console and type:

ulx adduser YourName superadmin

Type !xgui in chat to open the ULX admin menu where you can manage players and create custom ranks.

Step 7: Scan for Backdoors

The GMod addon ecosystem has a backdoor problem. Malicious addon authors sometimes include hidden Lua code that gives them remote access to your server. Zeros Host includes a Backdoor Scanner in the panel. Run it after installing any batch of addons. If the scanner flags a file, check which addon it belongs to and compare it against the addon's public Workshop version or GitHub source. Remove the addon if the flagged code is unexplained.

Running the scanner after every major addon install is good practice, not just a one-time step.

Step 8: Test and Invite Players

Connect to your server using the IP and port shown in the panel. Check that the gamemode loads correctly, Workshop addons are present, ULX works (!xgui in chat), and there are no Lua errors in the console on join. Share the IP and port with your players: they can connect via direct connect or by typing 'connect <ip>:<port>' in the developer console.

If players get 'missing map' or 'missing content' errors, check that the addon or map is in your Workshop collection and the collection ID is correctly set in server.cfg.