What is the result of configuring the following policy statement as a BGP import policy on the Alcatel-Lucent 7750 SR? policy-statement "Policy-1" entry 10 from protocol bgp prefix-list "List-1"…

Question

Options

• AAll BGP routes are rejected.
• BAll BGP routes are accepted.
• CAll routes matching prefix list "List-1" are rejected.
• DAll BGP routes matching prefix list "List-1" are rejected.

• A
  11% (3)
• B
  4% (1)
• C
  7% (2)
• D
  79% (22)

Explanation

Option D is correct because the from clause in entry 10 specifies two simultaneous match conditions: protocol bgp AND prefix-list "List-1". Both must be true for the reject action to fire - meaning only BGP-learned routes that also appear in List-1 are rejected. Everything else falls through to the default-action accept.

Why the distractors fail:

• A is wrong because the default action is accept, so BGP routes not in List-1 are permitted through.
• B is wrong because entry 10 explicitly rejects the subset of BGP routes that match List-1 - not all BGP routes are accepted.
• C is the classic trap: it drops the "BGP" qualifier from the match condition. In reality, a non-BGP route (e.g., OSPF, static) that matches List-1 would skip entry 10 (since protocol bgp wouldn't match) and be accepted by the default action. C would only be correct if the from clause had only prefix-list "List-1" with no protocol filter.

Memory tip: Read the from block as an AND gate - all listed conditions must match together. A policy entry is as specific as its most specific condition, so the reject applies only to the intersection of "is BGP" AND "is in List-1."

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