350-401 Practice Question: Consider the following BGP configuration: router…

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✗

  It sets the MED to 50 for all routes advertised to 10.0.0.2, but only if they match a prefix-list.

  Why it's wrong here

  This is incorrect because the route-map configuration shown has no match clause. Without a match clause, the permit statement automatically matches all routes, so MED 50 is applied to every advertised route. A prefix-list would only restrict matching if one were referenced via a match statement; since none is present, the 'only if they match a prefix-list' condition does not apply.

• ✓

  It sets the MED to 50 for all routes advertised to 10.0.0.2.

  Why this is correct

  The route-map is applied in the outbound direction to neighbor 10.0.0.2. The single permit sequence without a match clause matches all routes, and the set metric 50 command sets the MED to 50. Therefore, every route advertised to that neighbor will carry the MED value of 50. No filtering occurs; the route-map simply modifies the MED attribute for all outbound updates.

• ✗

  It sets the local preference to 50 for routes received from 10.0.0.2.

  Why it's wrong here

  This is incorrect for two reasons. First, the route-map is applied to outbound advertisements (as indicated by 'out' in the neighbor statement), not inbound, so it affects routes being sent to the neighbor, not received from it. Second, the set clause uses the metric keyword, which in BGP sets the MED, not local preference. Local preference is an attribute used within an autonomous system and is set with the set local-preference command. The route-map neither influences inbound routes nor sets local preference.

• ✗

  It filters all routes to 10.0.0.2 because there is no match statement.

  Why it's wrong here

  This is incorrect because a permit sequence without a match clause does not filter; instead, it matches everything. In a route-map, if no match command is present, the sequence is considered a match-all. The set clause is then applied to all routes. The route-map does not deny or filter any routes; it permits all and modifies the MED attribute. Filtering would require a deny statement or a match clause that excludes certain prefixes.

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