Methods and apparatus to detect border gateway protocol (BGP) session failures are disclosed. A disclosed example apparatus comprises a database interface to obtain provisioned configuration information for a provider edge (PE) router, a BGP engine to receive one or more BGP messages from a route reflector, the one or more BGP messages representing a list of active routes for the PE router, and a session analyzer to compare the list of active routes with the provisioned configuration information to determine whether a provisioned route is not present in the list of active routes, and to declare a BGP session failure when the provisioned route is not present in the list of active routes.