Q86 — AWS SAA-C03 Ch.15

Question 86 of 100 | ← Chapter 15

Q1186. A company is using an Amazon RDS for MySQL DB instance for a production application. During the company's upcoming scheduled maintenance window, a solutions architect will perform a major version upgrade to the DB instance.The application is critical, so the company wants to minimize the maintenance time and allow for a rollback if a problem occurs.Which solution will meet these requirements?

Correct Answer: C. Create a read replica of the DB instance. Upgrade the version on the read replica. Promote the read replica to be the primary DB instance. Direct the application to use the read replica endpoint.

Explanation

To meet the requirements of minimizing maintenance time and allowing for a rollback if a problem occurs during a major version upgrade of an Amazon RDS for MySQL DB instance, the best solution is C. Create a read replica of the DB instance. Upgrade the version on the read replica. Promote the read replica to be the primary DB instance. Direct the application to use the read replica endpoint.Analysis of Options:Option A: Enable the automatic upgrade option by using the AWS Management Console. Amazon RDS will apply the upgrade, which will occur during the scheduled maintenance window with no downtime. Limitation: While enabling automatic upgrades can simplify the process, major version upgrades typically require some downtime and do not guarantee no downtime. Additionally, there is no built-in rollback mechanism if the upgrade fails, which could lead to prolonged downtime and data loss. Option B: Create a new DB instance that has the desired version. Configure AWS Database Migration Service (AWS DMS) to migrate the existing data to the new DB instance. Change the DNS records to point to the new DB instance.Limitation: This solution involves creating a new DB instance and using AWS DMS to migrate data, which can be time-consuming and complex. It also requires changing DNS records, which could introduce additional downtime and potential issues if not managed carefully. There is no straightforward rollback mechanism if the migration or upgrade fails.Option C: Create a read replica of the DB instance. Upgrade the version on the read replica. Promote the read replica to be the primary DB instance. Direct the application to use the read replica endpoint. Advantage: This solution provides a safe and efficient way to perform a major version upgrade. By creating a read replica, you can upgrade the version on the replica without affecting the primary DB instance. If the upgrade is successful, you can promote the read replica to be the primary DB instance and direct the application to use the new endpoint. If the upgrade fails, you can simply discard the read replica and continue using the original primary DB instance, minimizing downtime and allowing for a rollback. Option D: Create a read replica of the DB instance. Configure a policy to fail over to the read replica if failure occurs during the upgrade. Upgrade the version on the primary DB instance. Limitation: While this solution involves creating a read replica, configuring a failover policy does not provide a straightforward rollback mechanism if the upgrade fails on the primary DB instance. Failover policies are typically used for high availability scenarios where the primary DB instance becomes unavailable, not for version upgrades. If the upgrade fails, you would still need to manually restore the primary DB instance from a backup or use another method to recover, which could be time-consuming and complex.Conclusion:C. Create a read replica of the DB instance. Upgrade the version on the read replica. Promote the read replica to be the primary DB instance. Direct the application to use the read replica endpoint. is the best solution to meet the requirements. It minimizes maintenance time, provides a straightforward rollback mechanism if the upgrade fails, and ensures that the application can continue to operate with minimal disruption.