AWS Certified Solutions Architect – Professional (SAP-C02) — Question 206

A company runs a microservice as an AWS Lambda function. The microservice writes data to an on-premises SQL database that supports a limited number of concurrent connections. When the number of Lambda function invocations is too high, the database crashes and causes application downtime. The company has an AWS Direct Connect connection between the company's VPC and the on-premises data center. The company wants to protect the database from crashes.

Which solution will meet these requirements?

Answer options

• A. Write the data to an Amazon Simple Queue Service (Amazon SQS) queue. Configure the Lambda function to read from the queue and write to the existing database. Set a reserved concurrency limit on the Lambda function that is less than the number of connections that the database supports.
• B. Create a new Amazon Aurora Serverless DB cluster. Use AWS DataSync to migrate the data from the existing database to Aurora Serverless. Reconfigure the Lambda function to write to Aurora.
• C. Create an Amazon RDS Proxy DB instance. Attach the RDS Proxy DB instance to the Amazon RDS DB instance. Reconfigure the Lambda function to write to the RDS Proxy DB instance.
• D. Write the data to an Amazon Simple Notification Service (Amazon SNS) topic. Invoke the Lambda function to write to the existing database when the topic receives new messages. Configure provisioned concurrency for the Lambda function to be equal to the number of connections that the database supports.

Correct answer: A

Explanation

Option A is correct because it uses Amazon SQS to buffer the writes to the database, preventing it from being overwhelmed by too many concurrent connections. The reserved concurrency limit on the Lambda function ensures that the number of concurrent executions does not exceed the database's capacity. The other options either do not address the concurrency issue effectively or introduce unnecessary complexity without solving the core problem.