In EIGRP topology,to prevent unnecessary querying, “spoke” routers in a “hub-and-spoke” environment can be configured as Stub routers. A stub router builds a neighbor adjacency with its hub router(s), and will inform neighbors of its stub status.
The stub router will still build the full topology table and it will still receives all routes from its neighbors by default.Once EIGRP stub is configured on router,it will immediately respond to any Query packets with an “Inaccessible” message. Neighbors will eventually stop querying the stub router, which helps EIGRP converge quicker and conserves bandwidth.
Router(config)# router eigrp < as_no.>
Router(config-router)# eigrp stub <receive-only / connected/ static/summary/ redistributed>
Router(config)# router eigrp 100
Router(config-router)# eigrp stub connected
EIGRP stub Command Options
Receive-only : Prevents the router from advertising any networks
Connected : Enables the router to advertise connected routes.These must either be included in a network statement or redistributed into EIGRP
Static : Enables the router to advertise static routes. They must be redistributed
Summary : Enables the router to advertise summary routes, both those created
manually and automatically.
Redistributed: Allows the router to advertise routes redistributed into EIGRP from another protocol or AS
The connected and static parameters will only advertise those networks if they have been injected into the EIGRP process, either using network statements or using route redistribution. By default, EIGRP stubs will only send connected and summary routes to neighbors.