Refer to the exhibit. A network engineer configured the redistribute connected subnets route-map filtering command on R1 to redistribute connected interfaces to the OSPF process. The engineer also…

Question

Exhibit

Options

• ARemove route-map sequence 30.
• BAdd a set statement to route-map sequence 20.
• CChange the deny statement in access list 2 to permit
• DRemove the subnets keyword from the redistribute connected subnets route-map filtering

• A
  5% (1)
• B
  14% (3)
• C
  76% (16)
• D
  5% (1)

Explanation

In a route-map used for redistribution, a 'match' clause references an ACL to identify prefixes. If the ACL has a 'deny' for 10.0.1.0/24, that prefix does NOT match the route-map sequence's match clause - it is simply skipped, not denied. The route-map then evaluates the next sequence (sequence 30), which likely has a 'permit' with no match condition (catch-all), allowing 10.0.1.0/24 to be redistributed. Changing the ACL 2 deny to a 'permit' causes 10.0.1.0/24 to match the route-map sequence's match clause. If that sequence has a 'deny' action, the prefix is then correctly denied from redistribution. The key concept: ACL deny within a route-map match clause means 'no match here', not 'deny this prefix'. The route-map's own permit/deny action is what controls redistribution once a match occurs.

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