Dedicated server guide

Garrys Mod

Manage gmodserver with AlphaGSM. Choose a runtime supported by the recorded module capabilities.

Recorded lifecycle pass · Support evidence: 2026-10-16.

Anonymous Workshop Process and Docker load passed for public dedicated-server content. Mod installation explains add, apply, and cleanup.

Build setup commands

Runtime familysteamcmd-linux

Declared runtimes: Docker or a Linux host process.

Network bindings

27015/UDP, 27015/TCP, clientport/UDP, sourcetvport/UDP. Named port values remain unknown; review the game guide and configuration for additional requirements.

Mods and plugins

Declared curated families: advdupe2, metamod, sourcemod, ulib, ulx. The optional sourcemod example installs its dependencies and applies the mod plan before launch. For Workshop content, use the setup builder with an actual game-compatible item ID; review supported content types in the guide. Anonymous Steam Workshop content for this module passed both process and Docker load. After setup, record an item with mod add workshop using a numeric ID or Steam Workshop URL, then run mod apply.

Backup hook

A module-specific backup hook is declared. Review the game guide for its scope, restore procedure and shutdown requirements.

Choose a supported runtime

Linux and Docker quickstart

Review the game guide for installation, account, licensing and runtime prerequisites before setup.

Docker

Complete interactive setup and review game-specific configuration before starting the server. Review the game guide for installation, account, licensing and runtime prerequisites before setup. Optional curated example: sourcemod. Omit all optional mod steps for a base server.

Start the Docker manager ./alphagsm-docker start
Create the game instance ./alphagsm-docker my-gmodserver create gmodserver
Complete interactive setup ./alphagsm-docker my-gmodserver setup
Optional: add metamod # Optional curated mod: sourcemod; add metamod ./alphagsm-docker my-gmodserver mod add manifest metamod
Optional: add sourcemod # Optional curated mod: sourcemod; add sourcemod ./alphagsm-docker my-gmodserver mod add manifest sourcemod
Optional: apply the mod plan # Optional: apply the mod plan ./alphagsm-docker my-gmodserver mod apply
Start the game server ./alphagsm-docker my-gmodserver start
Check the instance status ./alphagsm-docker my-gmodserver status

./alphagsm-docker start
./alphagsm-docker my-gmodserver create gmodserver
./alphagsm-docker my-gmodserver setup
# Optional curated mod: sourcemod; add metamod
./alphagsm-docker my-gmodserver mod add manifest metamod
# Optional curated mod: sourcemod; add sourcemod
./alphagsm-docker my-gmodserver mod add manifest sourcemod
# Optional: apply the mod plan
./alphagsm-docker my-gmodserver mod apply
./alphagsm-docker my-gmodserver start
./alphagsm-docker my-gmodserver status

Host process

Create the game instance ./alphagsm my-gmodserver create gmodserver
Complete interactive setup ./alphagsm my-gmodserver setup
Optional: add metamod # Optional curated mod: sourcemod; add metamod ./alphagsm my-gmodserver mod add manifest metamod
Optional: add sourcemod # Optional curated mod: sourcemod; add sourcemod ./alphagsm my-gmodserver mod add manifest sourcemod
Optional: apply the mod plan # Optional: apply the mod plan ./alphagsm my-gmodserver mod apply
Check the host prerequisites ./alphagsm my-gmodserver doctor
Start the game server ./alphagsm my-gmodserver start
Check the instance status ./alphagsm my-gmodserver status

./alphagsm my-gmodserver create gmodserver
./alphagsm my-gmodserver setup
# Optional curated mod: sourcemod; add metamod
./alphagsm my-gmodserver mod add manifest metamod
# Optional curated mod: sourcemod; add sourcemod
./alphagsm my-gmodserver mod add manifest sourcemod
# Optional: apply the mod plan
./alphagsm my-gmodserver mod apply
./alphagsm my-gmodserver doctor
./alphagsm my-gmodserver start
./alphagsm my-gmodserver status

This guide covers the gmodserver module in AlphaGSM.

gmodserver is currently PASSED on the documented Ubuntu 24.04 Linux baseline. The current GitHub integration lane still exercises both process and Docker runtime selection, and the validated Linux lifecycle stays aligned across both backends while local runs remain process-backed by default unless you opt into the Docker backend.

Requirements

AlphaGSM prefers the installed srcds_run_64 or srcds_run wrapper so the engine can load its bundled shared libraries. An explicit executable override continues to take precedence. If an existing installation saved srcds_linux64, run alphagsm mygmodserv set exe_name srcds_run before starting it to restore the wrapper's library setup.

screen
SteamCMD runtime libraries (lib32gcc-s1, lib32stdc++6)
Python packages from requirements.txt

Quick Start

Create the server:

alphagsm mygmodserv create gmodserver

Run setup:

alphagsm mygmodserv setup

Start it:

alphagsm mygmodserv start

Check it:

alphagsm mygmodserv status

Stop it:

alphagsm mygmodserv stop

Setup Details

Setup configures:

the game port (default 27015)
the install directory
the executable name
SteamCMD downloads the server files
SteamCMD also downloads common mountable Source content into _gmod_content/
default configuration and backup settings

Startup prefers the server's own launcher before searching downloaded game content. This keeps bundled TF2 launchers from changing the server's working directory in process and Docker runtimes.

Useful Commands

alphagsm mygmodserv update
alphagsm mygmodserv backup

Notes

Module name: gmodserver
Default port: 27015

Server variables

After create gmodserver, inspect or change these with set:

alphagsm myserver set --list
alphagsm myserver set KEY --describe
alphagsm myserver set KEY VALUE

Key	Aliases	Type	What it does
`map`	gamemap, startmap, level, worldname	string	The currently selected map or level. Example: `gm_construct`.
`maxplayers`	users	integer	Maximum number of player slots. Example: `16`.
`port`	gameport	integer	The primary game port. Example: `27015`.
`rconpassword`	rconpass, querypassword, query_administrator_password	string	Remote console password for administrative access. Stored as a secret.
`servername`	hostname, name	string	The server's public name shown to players. Example: `AlphaGSM Garrys Mod`.
`serverpassword`	sv_password, password	string	Password required for players to join the server. Stored as a secret.

Developer Notes

Run File

Executable: srcds_run
Location: <install_dir>/srcds_run
Engine: Source
SteamCMD App ID: 4020

Server Configuration

Config file: garrysmod/cfg/server.cfg
Mount config: garrysmod/cfg/mount.cfg
Depot config: garrysmod/cfg/mountdepots.txt
Key settings:
- hostname — Server name
- sv_maxrate — Max network rate
- rcon_password — Remote console password
Default port: 27015
Default map: gm_construct
Max players: 16
Ports:
- Game port: 27015 (UDP)
- Client port: 27005 (UDP)
- SourceTV port: 27020 (UDP)
Template: See server-templates/gmodserver/

Maps and Mods

Map directory: garrysmod/maps/
Mod directory: garrysmod/addons/
Mounted base content: AlphaGSM installs common Source content under _gmod_content/ and writes default mounts for Counter-Strike: Source, Half-Life 2: Deathmatch, and Team Fortress 2.
Workshop support: Individual IDs, official Steam Community URLs, and collection imports through mod add workshop / mod add workshop-collection.
Mod notes: AlphaGSM can now manage Garry's Mod addons from checked-in manifest entries plus direct url entries, GameBanana ids, and Mod DB page URLs. The local manifest currently includes popular admin/plugin stacks such as MetaMod, SourceMod, ULib, ULX, and AdvDupe2. Direct URLs can point at .gma files or supported archives; GameBanana and Mod DB currently install supported archives only, while checked-in manifest entries can now install either supported archives or single-file .gma assets. Garry's Mod addon archives that unpack as a bare addon root are installed under garrysmod/addons/<family-or-archive-name>/, so ulx can also pull in its checked-in ulib dependency automatically. mod cleanup removes only AlphaGSM-tracked addon files, clears its desired entries, and removes its addon cache under .alphagsm/mods/gmodserver/.
Map install: Copy .bsp files into garrysmod/maps/ and add to garrysmod/cfg/mapcycle.txt.
Mod install: Copy addon folders into garrysmod/addons/.

Workshop items are checked against the game AppID 4000 before being added or applied (the dedicated-server download uses AppID 4020). Collection imports expand public same-game collections into item desired state; later collection changes require another import. Only a single regular version-3 .gma payload is accepted per Workshop item. AlphaGSM validates its file table, paths, bounds and available CRCs before extracting it under garrysmod/addons/<workshop-id>/. The dedicated engine loads this addon folder at the next start. Direct URL and manifest GMA payloads use the same validation and extraction path. start applies enabled desired addons automatically unless mods.autoapply is false. Downloads use anonymous SteamCMD; unavailable, private, or entitlement-gated items fail with the provider's error. Stop a running server before applying or cleaning up addons, then start it again to reload mounted content.

This uses the same addon desired state and cleanup as manifest/URL addons. It does not write srcds_workshop_ids.txt or add host_workshop_collection to the launch command. Those are separate native download paths described in the Facepunch dedicated-server Workshop guide. For client-required assets, follow Facepunch's content serving guidance.

Examples:

alphagsm mygmod mod add workshop 557962238
alphagsm mygmod mod add workshop https://steamcommunity.com/sharedfiles/filedetails/?id=557962238
alphagsm mygmod mod add workshop-collection YOUR_PUBLIC_COLLECTION_ID
alphagsm mygmod mod remove workshop 557962238
alphagsm mygmod mod add manifest metamod
alphagsm mygmod mod add manifest sourcemod
alphagsm mygmod mod add manifest ulib
alphagsm mygmod mod add manifest ulx
alphagsm mygmod mod add manifest advdupe2
alphagsm mygmod mod add url https://addons.example.invalid/example-addon.gma
alphagsm mygmod mod add gamebanana 12345
alphagsm mygmod mod add moddb https://www.moddb.com/mods/example/downloads/example-addon-pack
alphagsm mygmod mod apply
alphagsm mygmod mod cleanup

Extra Content Notes

Facepunch recommends installing extra mounted content outside the server root; AlphaGSM follows that pattern with _gmod_content/.
mountdepots.txt is seeded with the default Garry's Mod depot set, including hl1, hl1_hd, hl2, episodic, ep2, and lostcoast.
Single-player Valve games such as Episode One, Episode Two, and Lost Coast still require an owned Steam account if you want to download their content manually.

Verify Workshop loading

The opt-in integration checks run the full AlphaGSM lifecycle in both process and Docker runtimes and load a fresh test-owned Lua probe through the running server console. They require the engine virtual filesystem to expose an addon-only file with the expected CRC for every selected item, and require the ULib and ULX fixtures to initialize their ULib.ucl.query and ulx.command APIs. Downloaded files alone do not count as successful loading. The test script avoids Source console input length limits and matches only a completed nonce-bearing probe. The default small fixture is the official ULib server addon; Valve's metadata reported public AppID 4000, title ULib, and size 246,309 bytes on 2026-10-13. The default collection fixture is sandbox server, whose public Valve collection response contained ULib and ULX on the same date. The full AlphaGSM collection lifecycle passed in process and Docker runtimes on 2026-10-13, including fresh API evidence for both addons and verified shutdown. The Docker run used the normal forced shutdown fallback after its stop timeout.

ALPHAGSM_RUN_INTEGRATION=1 ALPHAGSM_RUN_STEAMCMD=1 \
ALPHAGSM_RUN_GMOD_WORKSHOP=1 \
python3 -m pytest tests/integration_tests/test_gmodserver.py -k workshop

## Import and verify every item from your selected collection:
ALPHAGSM_RUN_INTEGRATION=1 ALPHAGSM_RUN_STEAMCMD=1 \
ALPHAGSM_GMOD_WORKSHOP_COLLECTION=YOUR_PUBLIC_COLLECTION_ID \
python3 -m pytest tests/integration_tests/test_gmodserver.py -k workshop_collection

ALPHAGSM_WORK_DIR=/path/with/enough/space GMOD_WORKSHOP_ITEM=557962238 \
make smoke-test SMOKE_TEST=run_gmodserver.sh
## Or use GMOD_WORKSHOP_COLLECTION=YOUR_PUBLIC_COLLECTION_ID.

Docker validation needs the local steamcmd-linux runtime image and daemon. An unavailable image or provider download is an unverified prerequisite; engine-probe timeouts remain failures.

Configuration templates

Reference files from this source revision. Review paths, passwords and game-specific settings before use.

server.cfg

Share your server

Sector Alpha server directory

When your server is ready, you can publish its connection details and community information on Sector Alpha. Review your listing and keep the information current.

Find a community

Browse the directory for game servers and their published connection details.

Browse server directory

Publish your server

Prepare a name, address and description for your listing.

Publish a server

Manual server sharing instructions

Frequently asked questions

What support evidence is recorded for Garrys Mod?

Recorded lifecycle pass. Review the game guide for installation, account, licensing and runtime prerequisites before setup.

Which runtimes can run Garrys Mod?

Declared runtimes: Docker or a Linux host process.

Which ports does Garrys Mod use?

27015/UDP, 27015/TCP, clientport/UDP, sourcetvport/UDP. Named port values remain unknown; review the game guide and configuration for additional requirements.

Can I add mods to Garrys Mod?

How should I back up Garrys Mod?

A module-specific backup hook is declared. Review the game guide for its scope, restore procedure and shutdown requirements.

Source and support evidence

This guide mirrors AlphaGSM’s upstream documentation at 32cef5ba9e03053c8e461fffa0ba133b160b528d. Commands and prerequisites can change. Check current support notes before installation.

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