Exam 300-410 topic 1 question 348 discussion

Actual exam question from Cisco's 300-410

Question #: 348
Topic #: 1

Refer to the exhibit A junior engineer updated a branch router configuration. Immediately after the change, the engineer receives calls from the help desk that branch personnel cannot reach any network destinations. Which configuration restores service and continues to block 10.1.1.100/32?

A. route-map FILTER-IN deny 5
B. ip prefix-list 102 seq 15 permit 0.0.0.0/32 le 32
C. route-map FILTER-IN permit 20
D. ip prefix-list 102 seq 5 permit 0.0.0.0/32 le 32

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Suggested Answer: C 🗳️

by forccnp at Feb. 23, 2023, 12:27 p.m.

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Highly Voted 1 year, 11 months ago

Selected Answer: C

I got tricked by not reading properly. Remember that a prefix list and a route map have an implicit deny at the end of their entries. The prefix list is permitting the host prefix so that it can be processed by the Route map. And it purposely leaves the implicit deny because the Route map only processes that host to deny it. However, the Route map implicitly denies everything else preventing other routes from being installed in the RIB

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Coffee_bean_master

Most Recent 1 year, 1 month ago

Selected Answer: C

Take a look at the route-map command where it has the keyword "deny" statement. If you were to have a second prefix list entry (seq 15 for example) on permitting everything else, it would still be denied because of the route-map key word "deny." Adding a second route-map entry with the key word "permit" would be the best option. Remember that if you have a route-map without any "matching" keywords, you are matching all traffic by default.

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forccnp

2 years, 4 months ago

Selected Answer: C

Given answer is correct

upvoted 2 times

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