AWS Certified Advanced Networking – Specialty (ANS-C01) — Question 141
A company has two AWS Direct Connect links. One Direct Connect link terminates in the us-east-1 Region, and the other Direct Connect link terminates in the af-south-1 Region. The company is using BGP to exchange routes with AWS.
How should a network engineer configure BGP to ensure that af-south-1 is used as a secondary link to AWS?
Answer options
- A. • On the Direct Connect link to us-east-1, configure BGP peering to use community tag 7224:7100 • On the Direct Connect link to af-south-1, configure BGP peering to use community tag 7224:7300 • On the Direct Connect BGP peer to us-east-1, set the local preference value to 200 • On the Direct Connect BGP peer to af-south-1, set the local preference value to 50
- B. • On the Direct Connect link to us-east-1, configure BGP peering to use community tag 7224:7300 • On the Direct Connect link to af-south-1, configure BGP peering to use community tag 7224:7100 • On the Direct Connect BGP peer to us-east-1, set the local preference value to 200 • On the Direct Connect BGP peer to af-south-1, set the local preference value to 50
- C. • On the Direct Connect link to us-east-1, configure BGP peering to use community tag 7224:7100 • On the Direct Connect link to af-south-1, configure BGP peering to use community tag 7224:7300 • On the Direct Connect BGP peer to us-east-1, set the local preference value to 50 • On the Direct Connect BGP peer to af-south-1, set the local preference value to 200
- D. • On the Direct Connect link to us-east-1, configure BGP peering to use community tag 7224:7300 • On the Direct Connect link to af-south-1, configure BGP peering to use community tag 7224:7100 • On the Direct Connect BGP peer to us-east-1, set the local preference value to 50 • On the Direct Connect BGP peer to af-south-1, set the local preference value to 200
Correct answer: B
Explanation
To ensure that af-south-1 is used as a secondary link, the Direct Connect link to us-east-1 should have a higher local preference value of 200 and use community tag 7224:7300, while the af-south-1 link should have a lower local preference of 50 and use community tag 7224:7100. Options A, C, and D do not correctly configure these parameters, leading to incorrect routing decisions.