AWS Certified DevOps Engineer – ProfessionalResilient Cloud SolutionsHard
A global software-as-a-service (SaaS) company needs to ensure its application is highly available and fault-tolerant across multiple AWS regions. The application consists of stateless web servers and a stateful database. The company requires an architecture that can automatically route users to the nearest healthy region and perform automated failover in case of a regional outage. Which combination of AWS services should be used to meet these requirements?
- AAmazon Route 53 with simple routing policy and EC2 instances with Auto Scaling groups in each region.
- BAmazon Route 53 with failover routing policy, health checks, and Aurora Global Database.
- CAmazon Route 53 with latency-based routing, health checks, and Amazon RDS Multi-AZ in each region.
- DAWS Global Accelerator with endpoint groups in each region and Amazon DynamoDB Global Tables.
Show answer & explanationAnswer & explanation
Correct answer: B. Amazon Route 53 with failover routing policy, health checks, and Aurora Global Database.
Route 53's failover routing with health checks can detect regional failures and automatically direct traffic to a healthy secondary region. Aurora Global Database provides fast, cross-region replication and RTO/RPO in minutes for the stateful database layer, enabling quick recovery from a regional disaster.
Why the other options are wrong
- A. Simple routing does not provide health checks or automatic failover. EC2 Auto Scaling is for regional availability, not cross-regional DR.
- C. Latency-based routing directs users to the lowest latency region but does not automatically failover if that region becomes unhealthy. RDS Multi-AZ provides high availability within a single region, not cross-regional disaster recovery with low RPO/RTO.
- D. AWS Global Accelerator can route traffic to the nearest healthy endpoint, but DynamoDB Global Tables, while multi-region, are eventually consistent by default for cross-region replication. For a 'stateful database' in a 'SaaS company' requiring high availability and fault tolerance, a relational database with strong consistency like Aurora Global Database is often preferred unless explicitly stated otherwise.
Route 53 Failover Routing with Aurora Global Database
This combination provides a robust multi-region disaster recovery solution where Route 53 automatically routes traffic to a healthy region based on health checks, and Aurora Global Database ensures low RPO/RTO for the relational database.
- Route 53 health checks monitor primary region health.
- Failover routing policy automatically switches DNS to secondary region.
- Aurora Global Database replicates data across regions with minimal lag.
- Secondary Aurora region can be promoted to primary for quick recovery.
Memory trick: Route 53 guides, Aurora Global saves the day.