We have plans in place to switch the default networking layer of Rust servers from RakNet to Steam Networking in late November or early December, further communication will follow.
This change requires servers to have a separate Steam query port set via the -queryport server startup parameter. When no query port is set, the server will default to either game port + 1 or rcon port + 1, depending on which number is larger.
Hosts of shared servers will need to ensure the query port is forwarded correctly, which is why we are making this announcement ahead of time. Servers can be switched over to Steam Networking for testing via the -swnet startup parameter, which we recommend doing ahead of time in order to ensure a smooth transition.