After creating ip prefix-list OFFICE seq 5 deny 172.16.0.0/16, which two additional commands are required so OSPF will not install that route? (Choose two.)
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Correct answer: ip prefix-list OFFICE seq 10 permit 0.0.0.0/0 le 32, distribute-list prefix OFFICE in under the OSPF process.
Why this is the answer
The ip prefix-list OFFICE seq 5 deny 172.16.0.0/16 command denies routes matching 172.16.0.0/16. Prefix lists have an implicit deny at the end, so to allow other routes, an explicit permit statement is needed. ip prefix-list OFFICE seq 10 permit 0.0.0.0/0 le 32 permits all other prefixes (0.0.0.0/0) with a length up to 32, ensuring other valid routes are not denied. The distribute-list prefix OFFICE in command, applied under the OSPF routing process, references the prefix list OFFICE and filters incoming OSPF routes based on its rules. This prevents OSPF from installing routes matching the denied entry into the routing table. Incorrect options: distribute-list OFFICE in is incorrect because it lacks the prefix keyword, which is necessary when referencing a prefix list. distribute-list OFFICE out would filter routes being advertised out of the OSPF process, not routes being received and installed. ip prefix-list OFFICE seq 10 permit 0.0.0.0/0 ge 32 would only permit host routes (/32), not all other valid prefixes.
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