Windows

SteamCMD

Dedicated servers are now downloaded using SteamCMD. This is a command line version of Steam.

You can download it from this page.

The first time you run it it will update and you will be left at a STEAM> console. You will want to log in. You can log into an anonymous account by typing:

Installing & Updating Garry's Mod Dedicated Server

If you want to specify a download folder then before you update enter this command:

You can then install or update the Garry's Mod Dedicated Server by using the command:

It will slowly download or update.

If you wish to verify your server, enter this instead of the above:

Once it's done you can type quit at the console to exit or just close the SteamCMD window.

Automated

You probably don't want to do that every time you want to install/update a server. Don't worry - it supports command lines too.

Running the server

After downloading and installing the server files you can now run the dedicated sever. You can either just run srcds.exe directly or use its command line interface like so:

After initial installation

After installing your server you should set up your GSL Token and the server's location.

GSLT

Please see Steam Game Server Accounts (GSLT) for help with sv_setsteamaccount. This is mandatory. Your server's ranking will be penalized if you do not do this.

Server operator rules

Please make sure your server conforms to Server Operator Rules.

Location flag

Next you should set your server's location. This is done via the sv_location console variable. The convar should directly correspond to a flag icon stored in the materials/flags16/ folder, without the .png extension. The maximum length is currently set to 5 characters. The flag icon filenames follow the ISO 3166-1 alpha-2 country codes. (http://www.famfamfam.com/lab/icons/flags/)

For example sv_location gb will display the Great Britain flag, sv_location us will display the USA flag, etc. European Union has a special case: sv_location eu

Steam Workshop

Optionally you can add +host_workshop_collection <collectionID> to your command line to automatically install workshop addons onto your dedicated server. Please see Workshop for Dedicated Servers for help with workshop for dedicated servers.

Setting startup gamemode

The active gamemode is set via the gamemode ConVar. As a command line parameter it can be applied as such: +gamemode sandbox, where sandbox is the name of the gamemode folder as it appears in garrysmod/gamemodes/ or in the gamemodes/ folder of any addon, including workshop addons. If you do know know the folder name of a workshop addon, it is very likely this information is provided in the addons' description. If not, you can ask the addon author.

The active gamemode can be changed at any time with the gamemode convar and then changing the map (see below).

Setting the startup map.

Setting startup maps works identically to setting startup gamemode, but using the map concommand. As a command line parameter it would look like so: +map gm_construct, where gm_construct is name of the map file without the .bsp extension, inside the garrysmod/maps/ folder, or inside the maps/ folder of any addon. Same rule applies to workshop addons - check the addons workshop page description for map file name.

To gracefully change the active map to a different map (or to simply reload the map), you can use the changelevel command, like so: changelevel gm_flatgrass.

Peer to Peer

Dedicated server can function in peer-to-peer mode. It can be turned on via the -p2p command line parameter. On startup the server will tell you how players can connect to such a server manually.

Hiding Your Server

hide_server convar, which when set to 1 will hide the server from the server browser. Ex: hide_server 1

Linux

Main article: Linux Dedicated Server Hosting

Installation

Install SteamCMD as per the recommendations from the Valve Developer Wiki.

Then install the GMod dedicated server in a similar manner to Windows:

The server is now available in ~/gmodds/.

Troubleshooting

If you get the error message

You are most likely running 64 a bit system and missing 32 bit libraries.

If the output of this command is x86_64, you are running a 64 bit system and need 32 bit libraries.

See this article on the valve wiki.
32-bit libraries on 64-bit Linux systems

macOS

macOS dedicated servers are no longer shipped.

The Experimental Branches

To update your server to a beta branch, you'll have to add the -beta <beta_name> to your app_update command.

The development branches are updated regularly, and may not be stable. See Dev Branch.

For the dev beta branch:

For the pre-release branch:

For the x86-64 branch:

Removing beta participation

To revert back to stable branch (NONE beta):