300-440 Question 31
Select 3A network administrator needs to implement policy-based routing (PBR) on a router to ensure that all HTTP traffic (port 80) from a specific subnet (192.168.10.0/24) is forwarded via a secondary WAN link (interface GigabitEthernet0/2) instead of the default route. Which of the following steps are required to achieve this configuration?
- A
Create an access control list (ACL) to match HTTP traffic from the 192.168.10.0/24 subnet.
- B
Define a route map and reference the ACL, specifying the next-hop IP address for the secondary WAN link.
- C
Apply the route map to the inbound traffic on the interface connected to the 192.168.10.0/24 subnet.
- D
Enable NAT on the secondary WAN interface to allow HTTP traffic to traverse the network.
- E
Configure a static route to the destination via the secondary WAN link.
Show answer and explanation
Correct answers: A, B, C
Explanation
Policy-based routing (PBR) allows network administrators to override the default routing behavior for specific traffic based on defined policies. In this scenario, HTTP traffic from the 192.168.10.0/24 subnet needs to be routed via a secondary WAN link. To achieve this, an ACL is required to match the traffic, a route map must define the policy, and the route map must be applied to the inbound interface. NAT and static routes are unrelated to PBR in this context.
- A. Correct.
Correct. To implement PBR, an ACL is used to match the specific traffic (HTTP from 192.168.10.0/24 in this case) that will be affected by the policy.
- B. Correct.
Correct. A route map is necessary to define the PBR policy, referencing the ACL and specifying the next-hop IP or interface for the secondary WAN link.
- C. Correct.
Correct. PBR policies (route maps) must be applied to the incoming interface where the matched traffic enters the router.
- D. Incorrect.
Incorrect. NAT is not required to implement policy-based routing. NAT is used for address translation, which is unrelated to PBR in this scenario.
- E. Incorrect.
Incorrect. Configuring a static route does not achieve PBR. Static routes influence the routing table, whereas PBR overrides the routing table for specific traffic as defined by the policy.