Check if your Rust server is online
A working Rust server shows up as offline on trackers so often because the port people join on and the port that answers queries are not the same.
Advertisement
The ports Rust uses
Server lists, and this tool, read the query port, which has its own number. With only the game port forwarded, everything seems fine — friends connect by IP — but the server never shows in the browser. Rust also has an RCON port. Keep that one closed to the internet; this tool will not test it.
Every port a default Rust install uses
With the game port left at 28015. If you changed it with +server.port, the other ports move with it.
| Port | What it is for |
|---|---|
| 28015 UDP | Game trafficRequired Rust is UDP-only for gameplay. A TCP-only rule looks correct in the router and connects to nothing. |
| 28017 UDP | Server browserRequired server.queryport, which defaults to game port + 2. Without it your server never appears in the browser, though people can still connect directly. |
| 28082 TCP | Rust+ companion appOptional Only if you want the mobile app to pair. Safe to leave closed. |
| 28016 TCP | RCONDo not forward rcon.port. A forwarded Rust RCON port is scanned within hours — it is one of the most actively probed ports in gaming. |
Advertisement
Still offline? Try this
Add a UDP rule for the query port next to the game port, then test again. If it still fails in the middle of a wipe-day rush, the server may just be too busy to reply before the timeout, since queries sit at the bottom of the queue under load. Wait for the crowd to settle before deciding anything is broken.
What a Rust server needs to run well
- Memory, 50 players
- 12 GB
- CPU cores
- 4+
- Disk
- 20 GB+
Very sensitive to single-core speed — this is where rubber-banding during firefights comes from.
What the checker asks a Rust server
Rust answers the standard Steam server query, over UDP, on its query port: 28017 on a default install, two above the game port. The reply carries the server name, the map and the player count, which is everything the in-game browser shows. The checker sends exactly that query, so a server that passes here is visible to the browser too, and one that fails is invisible to it, whatever its players see.
Online, but nobody can join
On the first Thursday of each month Facepunch ships the update that comes with the forced wipe, and every client updates with it. A server that has not been updated still runs and still answers queries, so the checker reports it online, but players are refused for running a different version. Update the server through SteamCMD (app 258550) as part of every wipe day, before anyone tries to join.