Amazon AWS Certified Developer Associate Exam Practice Questions (P. 2)

GPT-4o - Answer

To handle undeliverable Amazon SNS messages when a key deletion is scheduled, utilizing Amazon Simple Queue Service (SQS) as a dead letter queue (DLQ) is effective. This setup helps catch and store messages that fail to reach their destination due to various reasons, such as subscriber downtime or network issues, ensuring no critical notification is lost. Setting up SQS as a subscriber to the SNS topic allows for reliable reprocessing of these undeliverable messages, thus preserving the integrity and continuity of the notification system.

GPT-4o - Answer

Since the application consists of a single Docker image already built and pushed to a public registry, the most efficient deployment approach would involve using a previously configured Docker environment on AWS Elastic Beanstalk. The developer can utilize the Elastic Beanstalk CLI to create an environment and deploy the image. This involves referencing the image from the public registry directly within configuration files like Dockerrun.aws.json or docker-compose.yml, depending on whether Docker Compose is used. The correct deployment method leverages these tools for pulling the existing Docker image into the Elastic Beanstalk environment, not rebuilding the image from a Dockerfile.

GPT-4o - Answer

To meet the requirement of updating the production environment in increments of 10% until fully updated, the developer should indeed utilize the CodeDeployDefault.ECSLinear10PercentEvery3Minutes configuration. This configuration methodically deploys updates by shifting 10% of the traffic to the new version every three minutes, ensuring a gradual and controlled deployment. This is critical to avoid overwhelming the system with abrupt changes and allows for monitoring and adjustment if issues arise mid-deployment.

GPT-4o - Answer

In the context of decoupling a DB instance from an AWS Elastic Beanstalk environment, it's essential to understand that creating a new Elastic Beanstalk environment independently of the DB instance ensures that your application layer is separated from your database layer, facilitating better control and scaling. Meanwhile, creating a new DB instance from a snapshot of the existing DB aids in preserving the data state up to the point of the snapshot, allowing continued data consistency and integrity. This method would not result in data loss as the snapshot includes all the data until it was taken, though one should consider the possibility of a short downtime during the cutover if not properly managed.

GPT-4o - Answer

When scaling an Amazon RDS for MySQL, using Amazon Aurora MySQL with Auto Scaling on read replicas is generally more cost-effective. The Auto Scaling policy can adjust the count of the read replicas in response to the varying number of database connections, which aligns with load variations, such as a spike in transactions during the day. This solution efficiently manages increased workload and maintains performance during peak traffic times while minimizing costs during low usage periods at night. Notably, this answer presumes the need for effective read scaling despite the focus on transactions, which typically involve writes, as it addresses broader database performance needs under variable loads.