Rust server status checker
Rust separates the port players connect through from the port that answers queries, which is why a healthy Rust server so often shows as offline on trackers.
Which ports a Rust server needs
The query port is a different number from the game port, and it is the one this tool and every server list need. If you forwarded only the game port, your server works, your friends can connect by IP, and you will never appear in the server browser. Rust also exposes an RCON port — that one should not be open to the internet, and this tool will refuse to test it.
If it still shows offline
Forward the query port as UDP alongside the game port and retest. If it still fails during a wipe-day rush, the server may simply be too busy to answer within the timeout — queries are low priority under load, so retry once the population settles before concluding anything is broken.