SAP-C02 Design for New Solutions Practice Question

A company is designing a multi-region active-active application using Amazon Route 53 latency-based routing. The application runs on Amazon EC2 instances behind Application Load Balancers (ALBs) in two AWS Regions. The company needs to ensure that if one region becomes unavailable, traffic is automatically routed to the healthy region with minimal disruption. Which configuration meets these requirements?

⚠ Common exam trap

Watch out — candidates often assume failover routing is the only way to handle regional failures, but for active-active architectures, latency-based routing with health checks provides automatic failover while maintaining low-latency routing to both regions.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Configure Route 53 latency-based routing with health checks attached to each ALB endpoint.

Route 53 latency-based routing with health checks ensures that traffic is directed to the region with the lowest latency, and if an ALB endpoint fails its health check, Route 53 automatically removes it from DNS responses, routing traffic to the healthy region. This provides the required active-active multi-region failover with minimal disruption.

Answer analysis

Option-by-option breakdown

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

✗
Use Route 53 failover routing instead of latency-based routing.
Why it's wrong here
Failover routing serves one primary region with a standby, so both regions cannot actively serve latency-based traffic simultaneously. It would be correct for active-passive disaster recovery, whereas active-active across regions requires latency records with health checks attached to each region's endpoint.
✗
Configure Route 53 latency-based routing without health checks.
Why it's wrong here
Without health checks, Route 53 continues resolving the impaired region's records because it has no signal of failure, so clients keep hitting an unhealthy endpoint. Health checks are what enable automatic removal; latency records alone would be correct only when every endpoint is assumed always healthy.
✗
Use Route 53 weighted routing with weights set to 50 for each region.
Why it's wrong here
Weighted routing distributes traffic by fixed proportions regardless of endpoint health or user location, so a failed region still receives its 50 percent share. It would be correct for gradual canary deployments or blue-green splits, not for latency-based active-active failover between regions.
✓
Configure Route 53 latency-based routing with health checks attached to each ALB endpoint.
Why this is correct
Attaching Route 53 health checks to each ALB endpoint lets the DNS resolver withdraw an unhealthy region's records from latency-based answers, so clients resolve only the healthy region's ALB. This satisfies the automatic failover and minimal-disruption constraints, since failover occurs at DNS resolution without manual intervention or client reconfiguration.

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SAP-C02 Design for New Solutions Practice Question

Why each option matters

Option-by-option breakdown

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