AWS Certified Solutions Architect – Professional — Question 960

A company's application is increasingly popular and experiencing latency because of high volume reads on the database server.
The service has the following properties:
✑ A highly available REST API hosted in one region using Application Load Balancer (ALB) with auto scaling.
✑ A MySQL database hosted on an Amazon EC2 instance in a single Availability Zone.
The company wants to reduce latency, increase in-region database read performance, and have multi-region disaster recovery capabilities that can perform a live recovery automatically without any data or performance loss (HA/DR).
Which deployment strategy will meet these requirements?

Answer options

• A. Use AWS CloudFormation StackSets to deploy the API layer in two regions. Migrate the database to an Amazon Aurora with MySQL database cluster with multiple read replicas in one region and a read replica in a different region than the source database cluster. Use Amazon Route 53 health checks to trigger a DNS failover to the standby region if the health checks to the primary load balancer fail. In the event of Route 53 failover, promote the cross-region database replica to be the master and build out new read replicas in the standby region.
• B. Use Amazon ElastiCache for Redis Multi-AZ with an automatic failover to cache the database read queries. Use AWS OpsWorks to deploy the API layer, cache layer, and existing database layer in two regions. In the event of failure, use Amazon Route 53 health checks on the database to trigger a DNS failover to the standby region if the health checks in the primary region fail. Back up the MySQL database frequently, and in the event of a failure in an active region, copy the backup to the standby region and restore the standby database.
• C. Use AWS CloudFormation StackSets to deploy the API layer in two regions. Add the database to an Auto Scaling group. Add a read replica to the database in the second region. Use Amazon Route 53 health checks on the database to trigger a DNS failover to the standby region if the health checks in the primary region fail. Promote the cross-region database replica to be the master and build out new read replicas in the standby region.
• D. Use Amazon ElastiCache for Redis Multi-AZ with an automatic failover to cache the database read queries. Use AWS OpsWorks to deploy the API layer, cache layer, and existing database layer in two regions. Use Amazon Route 53 health checks on the ALB to trigger a DNS failover to the standby region if the health checks in the primary region fail. Back up the MySQL database frequently, and in the event of a failure in an active region, copy the backup to the standby region and restore the standby database.

Correct answer: A

Explanation

Option A is correct because it involves using Amazon Aurora with MySQL, which supports read replicas and cross-region replication, fulfilling the requirements for high availability and disaster recovery without data loss. The other options either do not provide the necessary database scalability or rely on backup restoration, which may not ensure live recovery without data loss.