The Dynamic BGP Peers lab exercise gave you the opportunity to build a large-scale environment in which routers having an approved source IP addresses (usually matching an ACL/prefix list) can connect to a BGP route reflector or route server.

In a more controlled environment, you’d want to define BGP neighbors on the BGP RR/RS but not waste CPU cycles trying to establish BGP sessions with unreachable neighbors. Welcome to the world of passive BGP sessions.

Click here to start the lab in your browser using GitHub Codespaces (or set up your own lab infrastructure). After starting the lab environment, change the directory to session/8-passive and execute netlab up.