AWS Certified Solutions Architect – Associate (SAA-C03)Design High-Performing ArchitecturesMedium
A global software company provides a SaaS application that serves customers across North America, Europe, and Asia. The application uses a multi-Region active-active architecture to ensure high availability and low latency. The company needs a DNS solution that directs users to the closest healthy application endpoint, automatically failing over to other healthy regions if an entire region becomes unavailable. Which Amazon Route 53 routing policy should be implemented?
- AWeighted routing policy
- BLatency routing policy with health checks
- CSimple routing policy
- DGeolocation routing policy
Show answer & explanationAnswer & explanation
Correct answer: B. Latency routing policy with health checks
Latency routing policy directs users to the region that provides the lowest latency. When combined with health checks, it identifies healthy endpoints and automatically fails over to the next best performing healthy region if an endpoint becomes unhealthy, perfectly matching the requirements for a global active-active architecture with automatic failover.
Why the other options are wrong
- A. Weighted routing policy distributes traffic based on weights, but doesn't inherently route to the lowest latency or handle automatic failover based on health checks (unless combined with other policies).
- C. Simple routing policy returns all records, with the client choosing one, offering no failover or latency-based routing.
- D. Geolocation routing policy routes based on the user's geographic location, not necessarily the lowest latency, and doesn't inherently provide automatic failover based on health status.
Route 53 Latency Routing
An Amazon Route 53 routing policy that directs user requests to the AWS region that provides the lowest network latency for that user.
- Improves application performance by serving users from the closest optimal region.
- Often combined with Route 53 health checks for automatic failover.
- Requires multiple endpoints (e.g., ALBs, EC2 instances) in different AWS regions.
- Uses latency measurements between DNS resolvers and AWS edge locations.
Memory trick: Route 53's way: Simple, Weighted, Latency's day, Geo's place, Failover's grace.