The system view is displayed.
The OSPF process view is displayed.
The OSPF area view is displayed.
The area is configured as a stub area.
The parameter no-summary prevents an ABR from sending Type 3 LSAs to the stub area.
The parameter default-route-advertise enables an ABR to generate default Type 3 LSAs and advertise them to the stub area.
The parameter backbone-peer-ignore prevents an ABR from checking the neighbor status when the ABR generates default Type 3 LSAs and advertises them to the stub area. Specifically, the ABR generates default Type 3 LSAs and advertises them to the stub area if there is an Up interface in the backbone area.
The cost of the default Type 3 route to the stub area is set.
The default value is 1.
To ensure the reachability of AS external routes to a stub area, the ABR in the stub area generates a default route and advertises the route to the non-ABR switches in the stub area.