ANS-C01 Question 439
Select 2Your company is deploying a multi-region web application using an Amazon VPC with private and public subnets. The application uses an Application Load Balancer (ALB) in each region to distribute traffic to EC2 instances in private subnets. To enhance fault tolerance and ensure cross-region failover, you need to implement a routing solution that directs users to the appropriate region based on application health. Which combination of AWS services and features should you use to achieve this?
- A
Amazon Route 53 with latency-based routing
- B
Amazon Route 53 health checks
- C
AWS Global Accelerator with endpoint groups for each region
- D
Amazon CloudFront with origin failover
- E
Elastic Load Balancing cross-zone load balancing
- F
AWS Transit Gateway for inter-region routing
Show answer and explanation
Correct answers: A, B
Explanation
To achieve cross-region failover and route traffic to the optimal region based on health and latency, Amazon Route 53 with latency-based routing and Route 53 health checks is the ideal solution. Route 53 can monitor the health of the ALBs in each region and ensure traffic is directed to the healthiest and nearest region. Other options, like AWS Global Accelerator and CloudFront, are not necessary or applicable for this specific use case.
- A. Correct.
Amazon Route 53 with latency-based routing is a suitable DNS-based solution for routing traffic to the region with the lowest latency, contributing to fault tolerance and performance.
- B. Correct.
Amazon Route 53 health checks are essential for monitoring the health of endpoints (e.g., ALBs) to ensure traffic is only directed to healthy regions.
- C. Incorrect.
AWS Global Accelerator is a networking service that improves global application performance, but it is not required in this scenario since Route 53 already handles cross-region routing for health checks and latency-based routing.
- D. Incorrect.
Amazon CloudFront's origin failover is designed for content delivery and static assets, not for routing application traffic across regions based on health or latency.
- E. Incorrect.
Elastic Load Balancing cross-zone load balancing ensures traffic distribution within a region but does not handle cross-region routing or failover.
- F. Incorrect.
AWS Transit Gateway is used for interconnecting VPCs across regions, but it is not relevant in this scenario where DNS-based routing is required for user traffic.