Introduce a Client<->Authserver packet that contains the IP-address of some server the client wants to connect to. The authserver then queries the status of that server (preferably in a database) and may warn the client or block the connection fully.
Introduce a Client<->Authserver packet that contains the IP-address of some server the client wants to connect to. The authserver then queries the status of that server (preferably in a database) and may warn the client or block the connection fully.