A SysOps administrator is configuring a highly available DNS solution for a critical web application. The application is hosted on EC2 instances behind an Application Load Balancer (ALB) in multiple AWS regions. The administrator needs to direct users to the nearest healthy endpoint based on their geographic location. If the primary region becomes unhealthy, traffic should automatically fail over to a healthy secondary region. Which Amazon Route 53 routing policy should be used?
- ALatency routing policy.
- BFailover routing policy combined with Geolocation routing.
- CGeolocation routing policy.
- DWeighted routing policy.
Show answer & explanationAnswer & explanation
Correct answer: B. Failover routing policy combined with Geolocation routing.
To meet both requirements, a Geolocation routing policy is needed to direct users to the nearest endpoint based on their location. To add automatic failover if that endpoint (or region) becomes unhealthy, health checks must be associated, and this is typically combined with a Failover routing policy. You can combine Geolocation routing with health checks to achieve regional failover based on user location.
Why the other options are wrong
- A. Latency routing directs to the region with the lowest latency, but doesn't inherently provide failover to a *specific* healthy secondary region if the primary fails.
- C. Geolocation routing directs based on user location but doesn't automatically fail over to another region if the primary becomes unhealthy without explicit health check configuration, which is best handled with a failover policy.
- D. Weighted routing distributes traffic based on weights, not geographic location or health-based failover.
Route 53 Geolocation & Failover Routing
Geolocation routing directs traffic based on user location, while Failover routing redirects traffic to a secondary resource if the primary becomes unhealthy, often used together for regional resilience.
- Geolocation: Directs users to nearest endpoint.
- Failover: Redirects if primary is unhealthy.
- Combine for location-aware, resilient applications.
Memory trick: To be 'Geo' (location-aware) and 'Failover' (resilient), combine the 'Geolocation' and 'Failover' policies.