Q9 — AWS SAA-C03 Ch.10

Question 9 of 100 | ← Chapter 10

Q609. A company runs a three-tier web application in the AWS Cloud that operates across three Availability Zones. The application architecture has an Application Load Balancer, an Amazon EC2 web server that hosts user session states, and a MySQL database that runs on an EC2 instance. The company expects sudden increases in application traffic. The company wants to be able to scale to meet future application capacity demands and to ensure high availability across all three Availability Zones.Which solution will meet these requirements?

Correct Answer: A. Migrate the MySQL database to Amazon RDS for MySQL with a Multi-AZ DB cluster deployment. Use Amazon ElastiCache for Redis with high availability to store session data and to cache reads. Migrate the web server to an Auto Scaling group that is in three Availability Zones.

Explanation

The solution that will meet the requirements of scaling to meet future application capacity demands and ensuring high availability across all three Availability Zones is: A. Migrate the MySQL database to Amazon RDS for MySQL with a Multi-AZ DB cluster deployment. Use Amazon ElastiCache for Redis with high availability to store session data and cache reads. Migrate the web server to an Auto Scaling group that is in three Availability Zones. Explanation: Option A suggests migrating the MySQL database to Amazon RDS for MySQL with a Multi-AZ DB cluster deployment. This provides high availability by automatically replicating the database to a standby instance in a different Availability Zone. Using Amazon ElastiCache for Redis with high availability ensures that session data is stored and can be accessed quickly. Redis's in-memory caching capability can improve the performance of the application by reducing database load. Migrating the web server to an Auto Scaling group that spans three Availability Zones allows for automatic scaling of the web server instances based on demand. This ensures that the application can handle sudden increases in traffic and provides high availability across all Availability Zones. Advantages of this solution include: \1. High Availability: Amazon RDS Multi-AZ deployment ensures that the database is replicated to a standby instance in a different Availability Zone, providing automatic failover in case of infrastructure issues. \2. Scalability: The use of an Auto Scaling group allows the web server instances to scale automatically based on demand. This ensures that the application can handle sudden increases in traffic and provide a consistent user experience. \3. Performance: Amazon ElastiCache for Redis provides in-memory caching, which can significantly improve the performance of the application by reducing the load on the database and serving frequently accessed data quickly. Compared to the other options, option A provides the best solution for meeting the requirements: B. Migrating to Amazon RDS for MySQL with a Multi-AZ DB cluster deployment and using Amazon ElastiCache for Memcached: While this option provides database high availability, it does not include Redis caching for improved performance. C. Migrating to Amazon DynamoDB with DynamoDB Accelerator (DAX): While DynamoDB is a highly scalable and managed NoSQL database, it may not be the best fit for a relational database like MySQL. Additionally, this option does not include Redis caching for session data. D. Migrating to Amazon RDS for MySQL in a single Availability Zone: This option lacks high availability as it does not utilize Multi-AZ deployment for the database. In summary, to meet the requirements of scaling to meet future capacity demands and ensuring high availability across all three Availability Zones, the recommended solution is to migrate the MySQL database to Amazon RDS for MySQL with a Multi-AZ DB cluster deployment, use Amazon ElastiCache for Redis with high availability for session data storage and caching, and migrate the web server to an Auto Scaling group spanning three Availability Zones (Option A). This provides a scalable, highly available architecture that can handle sudden increases in application traffic.