Q64 — AWS SAA-C03 Ch.16

Question 64 of 100 | ← Chapter 16

Q1264. A company is planning to improve the performance of a three-tier application by adding a cache layer to a MariaDB database. To ensure high availability, the company must create replicas of the primary cache node.Which solution will meet this requirement?

Correct Answer: A. Create an Amazon ElastiCache(Redis OSS) cache. Configure the application to connect to the cache.

Explanation

Let's analyze each option to determine which solution meets the requirement of adding a cache layer to a MariaDB database with high - availability replicas of the primary cache node:Option A: Create an Amazon ElastiCache (Redis OSS) cache. Configure the application to connect to the cache.High - availability: Amazon ElastiCache for Redis supports high - availability through features like Redis Cluster and Multi - AZ replication. Redis Cluster distributes data across multiple nodes, and Multi - AZ replication creates a standby replica in a different Availability Zone. If the primary node fails, the standby replica can be promoted to the primary, ensuring high availability. Caching for MariaDB: Redis can be used as an in - memory cache to store frequently accessed data from the MariaDB database, reducing the load on the database and improving application performance. So, this option meets the requirement.Option B: Deploy an Amazon CloudFront distribution, and set the application server as the origin. Configure a cache policy and an origin request policy.Functionality: Amazon CloudFront is a content delivery network (CDN) service. It is designed to deliver static and dynamic content to end - users with low latency by caching content at edge locations around the world.Not suitable for the requirement: It is not a cache layer for a database. It caches content at the edge of the network, not data from a MariaDB database to improve database performance. So, this option does not meet the requirement.Option C: Create an Amazon DynamoDB Accelerator (DAX) cluster. Configure the application to connect to the DAX cluster.Functionality: Amazon DAX is a fully managed, highly available, in - memory cache for Amazon DynamoDB. It is specifically designed to accelerate the performance of DynamoDB applications. Not suitable for the requirement: Since the database in question is MariaDB, not DynamoDB, DAX cannot be used as a cache layer for MariaDB. So, this option does not meet the requirement. Option D: Create an Amazon ElastiCache (Memcached) cache. Configure the application to connect to the cache.High - availability limitations: Amazon ElastiCache for Memcached is a simple in - memory caching system. While it can be used to cache data from a database, it does not have built - in high - availability features like Multi - AZ replication out of the box. Memcached is a distributed caching system that can be scaled horizontally, but it does not provide automatic failover mechanisms like Redis. So, this option does not fully meet the requirement of high - availability replicas.Therefore, the solution that will meet the requirement is Option A.