AWS Certified Solutions Architect – Associate (SAA-C03) — Question 864

A company that runs its application on AWS uses an Amazon Aurora DB cluster as its database. During peak usage hours when multiple users access and read the data, the monitoring system shows degradation of database performance for the write queries. The company wants to increase the scalability of the application to meet peak usage demands.

Which solution will meet these requirements MOST cost-effectively?

Answer options

• A. Create a second Aurora DB cluster. Configure a copy job to replicate the users’ data to the new database. Update the application to use the second database to read the data.
• B. Create an Amazon DynamoDB Accelerator (DAX) cluster in front of the existing Aurora DB cluster. Update the application to use the DAX cluster for read-only queries. Write data directly to the Aurora DB cluster.
• C. Create an Aurora read replica in the existing Aurora DB cluster. Update the application to use the replica endpoint for read-only queries and to use the cluster endpoint for write queries.
• D. Create an Amazon Redshift cluster. Copy the users' data to the Redshift cluster. Update the application to connect to the Redshift cluster and to perform read-only queries on the Redshift cluster.

Correct answer: C

Explanation

Adding an Aurora read replica to the existing cluster is the most cost-effective and efficient way to offload read traffic from the primary instance, resolving the write performance degradation. Amazon DynamoDB Accelerator (DAX) is designed for DynamoDB and cannot be used with Aurora. Creating a second cluster or utilizing Amazon Redshift for transactional reads adds unnecessary cost, latency, and architectural complexity.