Game port and query port: why there are two
A Rust server uses several UDP ports with different roles. Mixing them up is a common cause of “server not visible” and “cannot connect”.
Port roles
Game port (usually 28015) — players connect through it with the connect command.
Query port (usually 28016) — answers server-list and monitoring queries: online count, name, map.
RCON port — for administration. We never query it and never ask for RCON passwords.
Why ports do not have to be consecutive
Hosting providers allocate ports arbitrarily. The guess “query = game + 1” is often wrong, so we store the ports separately.
Our monitoring queries only the explicitly given query port and never scans neighbouring ports.
What this means for you
Owners: provide both ports when adding a server — monitoring starts immediately, without guesses.
Players: if connect fails, the cause is almost always a wrong game port, not the query port.