SAP-C02 Continuous Improvement for Existing Solutions Practice Question

A company runs a web application on Amazon EC2 instances in an Auto Scaling group. The application uses an Amazon RDS for MySQL database. The company wants to improve the performance of read-heavy workloads and reduce the load on the primary database instance. The application currently connects to the primary instance for all read and write operations. The solutions architect needs to implement a solution that requires minimal changes to the application code. Which approach should the solutions architect recommend?

⚠ Common exam trap

The trap here is assuming that Multi-AZ deployments can be used for read scaling, when in fact the standby instance is not accessible for read operations.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Create an RDS read replica and configure the application to direct read queries to the read replica endpoint.

Creating an RDS read replica and directing read queries to it is the most straightforward way to offload read traffic from the primary database. It requires only a change to the application's connection configuration for read operations, with no schema changes or major code modifications. This improves read performance and reduces load on the primary instance, addressing the company's needs effectively.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
Migrate the database to Amazon Aurora MySQL and enable Aurora Auto Scaling for read replicas.
Why it's wrong here
Migrating to Aurora MySQL and using Auto Scaling for read replicas can improve read scalability, but it requires a database migration, which is a significant change and may involve downtime. The scenario asks for minimal changes to the application code, but migration also involves infrastructure changes. While Aurora is a powerful solution, it is not the least invasive option here. The existing RDS for MySQL can support read replicas without migration.
✓
Create an RDS read replica and configure the application to direct read queries to the read replica endpoint.
Why this is correct
RDS read replicas are designed to offload read traffic from the primary instance. By creating a read replica and updating the application to send read queries to the replica's endpoint, you can distribute the read load and improve performance. This requires minimal code changes, typically just changing the connection string for read operations. It is a standard and effective solution for read-heavy workloads.
✗
Enable Multi-AZ deployment for the RDS instance to automatically offload read traffic to the standby instance.
Why it's wrong here
Multi-AZ deployments are for high availability and disaster recovery, not for scaling read operations. The standby instance in a Multi-AZ setup does not serve read traffic; it only takes over in the event of a failure. Enabling Multi-AZ will not reduce the read load on the primary instance. Therefore, this does not meet the requirement to improve read performance.
✗
Use Amazon ElastiCache for Redis to cache the results of frequent read queries.
Why it's wrong here
Caching with ElastiCache can reduce read load on the database, but it requires application code changes to implement cache logic, such as checking the cache before querying the database and updating the cache on writes. This is more invasive than simply redirecting read queries to a read replica. Additionally, caching introduces complexity around cache invalidation and consistency. While caching is a valid optimization, it does not meet the minimal code change requirement as directly as read replicas.

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SAP-C02 Continuous Improvement for Existing Solutions Practice Question

Why each option matters

Option-by-option breakdown

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