You might want to include maps from Counter-Strike or Team Fortress on your server. Updating and copying the maps over can be a pain.
With mount.cfg you can specify folders to add to the filesystem. Garry's Mod will scan the folder, mount any sub-folders and vpk files inside the given folder.
mount.cfg is located in garrysmod/cfg/ and can be opened by any plain text editor - and should look something like this:
The key names ("tf", "cstrike" and "episodic" in this example) in the file tell Garry's Mod which game this path is for, i.e. which game should be marked as mounted for you. This affects IsMounted and subsequently tells addons which games are mounted and which aren't.
This method will also allow you to mount games (or folder addons) into Hammer Editor.
If you are experiencing:
- Your clients are unable to spawn Hunters or NPCs from Half-Life: Source
- Spawning the Jalopy doesn't do anything
- Addons complaining that game content is not installed on the server, despite it being installed
Then you may need to ensure mountdepots.txt exists in garrysmod/cfg/ with contents resembling:
This will tell Garry's Mod that those games are installed and should be mounted (regardless of whether they are actually installed or not)
Mounting necessary games using the method above should resolve the issues as well.