On a city’s dual-plane bearer network, PE1-A and PE1-B are two PEs in different planes of the city. Three CEs are on the same VPN. The OSPF is used to exchange VPN route information between CE 1 and PE1-A and between CE 2 and PE1-B. The default route leading to PE1-A is configured on CE 3, and a static route leading to CE 3 is configured on PE1-A. The static route is imported to the OSPF, and the OSPF route is imported to the VPN instance of the BGP. The MP-IBGP neighbor relationship is established among the PEs. Subinterfaces are enabled in the links between PEs and are bound to the same VPN to exchange VPN route information between PEs .
How many routes on PE1-B can reach CE 3?
A. Only one (The route leading to CE 3 is learned based on the IBGP neighbor relationship between PEs. The other route is filtered out by OSPF loopback detection.)
B. Two (One route is learned based on the IBGP neighbor relationship between PEs, and the other one is the OSPF category-5 route.)
C. No route
D. Only the OSPF category-5 route can reach CE 3.
Answer: C
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