Every Rust Startup Variable Explained

Rust is configured through its startup command rather than a settings file, and your panel exposes every part of it as a variable you can edit. This page walks through all of them, so you can find the one you want instead of guessing.

1Open the Startup Page

• Log in to your game panel and click your Rust server.
• Click Startup in the left menu under CONFIGURATION.
• The Startup command at the top is the assembled result. Below it, Variables is where you change the parts.
• Variables save as you type, but the server only reads them when it boots, so a restart is always the second half of the job.

2Your Server Listing, and Where It Really Lives

HOSTNAME, DESCRIPTION, SERVER_URL, SERVER_IMG, SERVER_LOGO and MAX_PLAYERS all still exist here, but this is no longer where you should set them.

Rust settings does the same job with a live preview of the in-game browser, hosts your images for you, and handles the gameplay rules that have no startup variable at all. Use that page, and treat these variables as the plumbing underneath it.

3The World

• Level (LEVEL) is the world type, normally Procedural Map.
• World Size (WORLD_SIZE) sets how large a procedural map is. 3000 to 4500 is the usual range: smaller feels busier with fewer players, larger feels empty.
• World Seed (WORLD_SEED) picks which map is generated. The same seed always produces the same island.
• Custom Map URL (MAP_URL) replaces the generated map with a downloaded one, and overrides size and seed. An invalid URL crashes the server on boot, so check it before restarting.

Changing size or seed only takes effect on a fresh map. See how to wipe your Rust server.

4Players and Saving

• Max Players (MAX_PLAYERS) is the slot count.
• Save Interval (SAVEINTERVAL) is how often the world is written to disk, in seconds. Much lower costs performance, much higher costs progress when something goes wrong.
• Save interval also appears under Advanced in Rust settings, which writes it to server.cfg. Set it in one place. If the two disagree, the one in server.cfg is applied after the command line and wins.

5Ports

All three are read only because we assign them, but it helps to know what they do.

• RCON Port (RCON_PORT) is for remote administration tools. See how to connect with RCON.
• App Port (APP_PORT) is the Rust+ companion app. See how to connect the Rust+ app.
• Query Port (QUERY_PORT) is what the server browser uses to see your server. If your server is running but invisible, this is part of the answer: why your server is not in the browser.

RCON Password (RCON_PASS) is editable and worth changing from the generated default if you hand RCON access to anyone.

6Modding and Branch

• Modding Framework (FRAMEWORK) accepts vanilla, oxide or carbon. The Framework page does the same thing with one click and is the easier route.
• Rust Branch (RUST_BRANCH) chooses release or staging. Leave it on release. Staging runs Facepunch's test build, which normal players cannot join, so a server accidentally left there looks broken to everyone.

7Additional Arguments

Additional Arguments (ADDITIONAL_ARGS) appends anything else to the startup command, which is how you reach settings that have no variable of their own. Separate multiple arguments with spaces:

+server.tags "pve,weekly" +server.password "letmein"

• Tags no longer belong here: set them in Rust settings, which knows the valid ones. This field is for the rest, such as a server password if you want a private server.
• Because it is part of the startup command, anything here is reapplied on every boot, so it survives wipes and updates.

Good to Know

• Restart or nothing changes. The variables are read once, at boot.
• The startup command shows the truth. If a setting does not seem to apply, read the assembled command at the top of the page and check your value actually appears in it.
• Console changes are not the same thing. A convar set with a console command lasts until restart unless you run server.writecfg. A startup variable is applied every time. When the two disagree, the startup command wins on boot.

Finished

You know what every variable does. For the things that live in the console instead, see Rust admin commands.