300-410 Question 137
Select 3A network engineer is configuring a BGP neighbor relationship between two routers in different autonomous systems. They require the configuration to support authentication, avoid private AS numbers, and ensure that BGP updates are exchanged without requiring a direct connection between the routers. Which of the following configurations must be correctly implemented to meet these requirements?
- A
Enable BGP multihop on both routers and set a TTL value greater than 1.
- B
Configure MD5 authentication for the BGP neighbor relationship.
- C
Enable route refresh capability on both routers.
- D
Remove private AS numbers from the AS path using the 'remove-private-as' command.
- E
Set the BGP synchronization feature to ensure consistent IGP and BGP routing tables.
Show answer and explanation
Correct answers: A, B, D
Explanation
To establish a BGP neighbor relationship between routers in different autonomous systems without direct connection, BGP multihop must be enabled. MD5 authentication is necessary to secure the connection. Additionally, the removal of private AS numbers is required to meet the scenario's criteria. Route refresh and synchronization, while useful in specific contexts, are not directly relevant to this use case.
- A. Correct.
Correct. Enabling BGP multihop allows BGP peering to occur even if the routers are not directly connected. A TTL value greater than 1 is required for this setup.
- B. Correct.
Correct. MD5 authentication ensures secure BGP neighbor relationships by verifying the identity of the peers.
- C. Incorrect.
Incorrect. While route refresh capability is useful for updating routes dynamically, it is not mandatory for the specific requirements of the scenario.
- D. Correct.
Correct. The 'remove-private-as' command is used to strip private AS numbers from the AS path, meeting the requirement to avoid private AS numbers.
- E. Incorrect.
Incorrect. BGP synchronization is an older feature and is not required in modern networks, especially when the routers are not directly connected.