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AWS Certified Solutions Architect - Associate: DNS Configuration for Failover
Explore a key question on AWS DNS configurations for failover and learn how to choose the right option.
An application must direct users to a secondary Region automatically if the primary Region becomes unhealthy. Which DNS configuration supports this?
The question
- A. Route 53 simple routing
- B. Route 53 failover routing with health checks
- C. A single A record with a static IP
- D. CloudFront origin failover only
Think before you scroll
Consider how DNS configurations can manage failover scenarios. The right choice should ensure that users are redirected to a secondary Region without manual intervention when the primary fails.
The answer
The correct option is B. Route 53 failover routing with health checks. This option allows automatic redirection to a secondary endpoint if the primary endpoint fails health checks.
Why the other options lose
- A. Route 53 simple routing: This option directs traffic to a single resource without considering health status. If the primary endpoint fails, users do not redirect automatically to a secondary location.
- C. A single A record with a static IP: This option does not provide any failover capabilities. If the primary resource fails, users cannot be redirected since the DNS entry points to a fixed IP without health checks or alternative routing.
- D. CloudFront origin failover only: This option is limited to CloudFront distributions and does not apply to DNS-level failover for applications needing to redirect users between Regions. It lacks the health check functionality required for automatic failover.
The concept behind it
Failover routing in Route 53 is designed to maintain application availability by monitoring the health of resources. When configured with health checks, it actively checks the status of the primary endpoint and automatically redirects traffic to a secondary endpoint if the primary becomes unhealthy. This ensures consistent user access to applications even during outages.
Exam trap to remember
Always choose routing options that include health checks for automatic failover in multi-region applications. This principle ensures high availability and user access under failure conditions.