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Difficulty: HardRoute 53 Routing Policies and DNS Failover Strategies

A company is deploying a global application across two AWS Regions: us-east-1 and eu-central-1. The application consists of web servers behind an Application Load Balancer (ALB) in each region, and a multi-region database. The solutions architect needs to design an Amazon Route 53 DNS routing strategy that directs users to the closest region with the lowest network latency, but automatically redirects traffic to the other region if the ALB or the backend database in one region becomes unhealthy. Which combination of configurations should the solutions architect implement to meet these requirements? (Select TWO.)

  1. Create Route 53 Alias records with a Latency routing policy pointing to the ALB in each region, and configure Evaluate Target Health to Yes.Answer
  2. Configure the ALB target group health checks in each region to monitor an application health endpoint that verifies both the web server status and database connectivity.Answer
  3. C
    Create Route 53 CNAME records with a Latency routing policy pointing to the ALB DNS names in each region, and enable Evaluate Target Health on these records.
  4. D
    Create Route 53 Failover routing records for both regions, designating the us-east-1 ALB as the primary record and the eu-central-1 ALB as the secondary record.
  5. E
    Create Route 53 Latency routing Alias records and manually configure the record TTL to 10 seconds to ensure faster client-side failover.

Answer

Create Route 53 Alias records with a Latency routing policy pointing to the ALB in each region with Evaluate Target Health set to Yes, and configure the ALB target group health checks to monitor a path that validates both the web server and database connectivity.
The correct architecture uses Route 53 Alias records with a Latency routing policy and 'Evaluate Target Health' enabled to route users based on lowest latency and monitor ALB health. To propagate database failures to Route 53, the ALB target group health check must monitor an endpoint that validates the backend database. When the database fails, the ALB targets fail health checks, causing the ALB to report as unhealthy, which prompts Route 53 to stop routing traffic to that region.

Step-by-Step Solution

1
Determine the appropriate Route 53 routing policy for lowest latency.
Latency routing policy must be used to direct users to the region that offers the lowest network latency.
Failover or other policies do not dynamically route based on latency performance.
2
Select the correct record type that supports health evaluation for the load balancer.
Use Alias records (pointing to the ALBs) instead of CNAME records, and enable 'Evaluate Target Health'.
'Evaluate Target Health' is only supported on Alias records and allows Route 53 to automatically monitor target group health.
3
Integrate the database status into the health check path.
Configure the ALB target group health check to query a deep health path (like `/health`) that verifies the backend database connection.
If the database goes down, target instances will fail their health checks, the ALB will report as unhealthy, and Route 53 will failover traffic.

Key Concept

Route 53 DNS failover using Latency routing policies combined with ALB Evaluate Target Health.
Estimated Time:2m 0s
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Topics

Route 53 Routing Policies and DNS Failover Strategies

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