How do I set up a Garry's Mod sandbox server?
Garry's Mod starts in sandbox mode by default, so no gamemode change is needed. The key configuration is in garrysmod/cfg/server.cfg.
Essential settings for a sandbox server: sv_downloadurl "" (set this if you use a FastDL or Workshop content server), sv_allowupload 0 and sv_allowdownload 1 to control client file transfers, sbox_maxprops 100 to limit how many props each player can spawn (default is 200; lower it on high-player-count servers to reduce lag), and sbox_maxragdolls 5 and sbox_maxnpcs 10 to cap spawnable entities.
For Workshop content, open the Workshop Addon Manager (Workshop Search in the sidebar), switch to the Collection tab, and paste in a collection ID. Players download required content automatically on connect.
For admin management, install ULX and ULib via Addon Manager, then use the Admin Ranks page to assign superadmin to your SteamID. The standard ULX rank structure works well for sandbox: user (base), moderator (freeze, remove props, kick), admin (ban, change maps), superadmin (full access).
Run the Backdoor Scanner after adding any third-party addons. Free sandbox addons on the Workshop sometimes contain hidden remote access code.
Want to try this on a real server?
Everything described here is available on the trial too, on the same hardware and the same panel as the paid plans. Try it free for 24-hour, no credit card required.
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