400-007: Cisco Certified Design ExpertDemo

Question

Question Image

Refer to the exhibit. The Company XYZ BGP topology is illustrated in the diagram. The LA router interface toward the 10.1.5.0/24 network is faulty and repeatedly goes up and down, affecting the entire routing domain. Which routing technique can the network administrator use so the rest of the network is unaffected by this flapping issue?

A The LA administrator should use route dampening for the 10.1.5.0/24 network so that it does not get propagated when it flaps up and down.
B The Chicago administrator should use route filtering to block the 10.1.5.0/24 network from coming in from the LA router.
C The LA administrator should use route aggregation to summarize the 10.1.4.0/24, 10.1.5 0/24, 10.1.6.0/24, and 10.1.7.0/24 networks toward Chicago.
D The LA administrator should use route filtering to block the 10.1.5.0/24 network from getting propagated toward Chicago and New York.

Explanation

BGP route dampening reduces propagation of an unstable, flapping prefix by assigning penalties to repeated withdrawals and announcements. When the accumulated penalty reaches the configured suppression limit, BGP temporarily suppresses advertisements of that prefix; it is advertised again after the penalty decays and the route is stable. This contains the 10.1.5.0/24 flapping updates without permanently filtering the route. Cisco: Route dampening

Learn more

Cisco — Route dampening

400-007: Cisco Certified Design ExpertDemo

AstroTutor

Notes

Readiness

QuestionQ328

Community Discussion