An internal-facing application is available in two AWS regions (Region 1 and Region 2). Each region has its own Application Load Balancer (ALB) and target group. The company uses an AWS Route 53 private hosted zone to route clients to Region 1 by default, but it must automatically fail over to Region 2 when Region 1’s ALB is unhealthy. Which Route 53 design best meets this requirement?

Use latency-based routing with two alias records; Route 53 will automatically shift traffic away from the unhealthy region.

Latency-based routing selects the record with the lowest measured latency. It does not provide deterministic failover based on health check status, so traffic may continue to be routed to an unhealthy ALB if it has lower latency.

Use weighted routing with weights 100/0 and update weights manually after detecting failures.

Weighted routing changes traffic distribution only when weights are changed. Manual updates are not automatic failover and can introduce delays and operational risk during incidents.

Use geolocation routing with a single alias record for Region 1, and enable EDNS Client Subnet to detect unhealthy endpoints.

Geolocation and EDNS Client Subnet affect which record is returned based on client location/network information. They do not evaluate ALB health and therefore cannot trigger automatic regional failover.

What does this SAA-C03 question test?

CIDR notation defines the prefix length.

What is the correct answer to this question?

The correct answer is: Use failover routing with two alias A records for the same name: one PRIMARY and one SECONDARY, both pointing to each region’s ALB; attach the health check to the PRIMARY record. — For automatic regional failover, Route 53 must use a failover routing policy driven by health checks. With failover routing, you create two records for the same name—one marked PRIMARY and another marked SECONDARY—typically as alias records to each region’s ALB. You associate a health check with the PRIMARY record (for example, HTTPS checks to an ALB health endpoint). When the health check indicates the primary ALB is unhealthy, Route 53 automatically returns the secondary region’s alias until the primary becomes healthy again. Latency-based routing chooses the lowest-latency endpoint and does not inherently switch based on health check failures. Weighted routing requires weight adjustments to change traffic distribution and is not a failover-by-health mechanism by default. Geolocation/EDNS Client Subnet do not perform health evaluation, so they cannot satisfy the automatic failover requirement.

What should I do if I get this SAA-C03 question wrong?

Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.