DedicatedServerConfig.json: tuning your Foundry server

The entire behavior of a dedicated Foundry server lives in a single text file: DedicatedServerConfig.json, written automatically on first launch. Knowing it means avoiding needless restarts and worlds created by mistake. Let's go over the settings that genuinely weigh on a smooth co-op session.

The config file's skeleton

• World name: it serves as the display name and the save folder name. Changing it later doesn't rename your world, it starts a blank one, so set it from the outset.
• Password: the gate of a private server. Only leave it empty if you fully accept a factory open to anyone.
• Slots: the cap on simultaneous players. Foundry is usually played at 4-8; align this figure with your RAM and your CPU's clock speed.
• Auto-save: set a regular interval. A crash with no backup means an entire factory wiped off the map.
• UDP port: to carry over into the port forwarding rule if you're self-hosting.

RAM, the lifeblood of the factory simulation

Foundry doesn't just store a map: it simulates conveyors, machines and ore flows in real time. Every new building adds memory load. Too tight an allocation shows up as micro-stutters on the server side as soon as the base spreads out. To gauge the tiers by your factory's size, see our article on the price of a Foundry server.

Three moves that stabilize the server

• Keep the server up to date: Foundry patches regularly optimize the simulation engine.
• Space out backups sensibly so you don't freeze the game every cycle.
• Bet on per-core clock speed rather than core count, a detail expanded on in our comparison of Foundry hosts.

A reflex to burn in: any change to DedicatedServerConfig.json only takes effect after a full server restart.

The no-text-editor version

On a Foundry server hosted by Fly-Serv, FlyPanel edits DedicatedServerConfig.json from a readable interface: you change the password or the slots live, schedule backups and restart the server with one button, without ever opening SteamCMD. Compare the Foundry hosting plans starting at 3,99 €/month.