QuestionQ219

Routing Policy and Manipulation

Question Image

Refer to the exhibit. Following a recent network implementation project, customer A is conducting stress testing to confirm network redundancy at the branch office connected to R4. When the link from R2 is shut down as shown, the SLA tracking object fails and the cost of the link between R2 and R4 rises to 100. However, a traceroute from a PC in the branch office indicates that traffic to HQ is still routed through R2. Which solution resolves the issue and optimizes traffic flow through R3 without introducing operational overhead?

  • A Use multiarea adjacency to extend Area 10 to the link between R2 and R3.
  • B Create a virtual channel from R3 to R4.
  • C Configure two OSPF processes on R2 and R3 and redistribute traffic between them.
  • D Redistribute routes from BGP to OSPF as type E1.
Explanation

An OSPF E1 external route uses the advertised external metric plus the internal OSPF cost to reach the ASBR. Redistributing the BGP routes into OSPF as E1 therefore makes the increased R2–R4 cost affect the total path calculation, allowing the lower-cost route through R3 to be selected. This avoids the additional design and operational complexity of virtual links, multi-area adjacency, or redistribution between separate OSPF processes.

Learn more

Community Discussion

No comments yet. Be the first to start the discussion!