Which steps should be taken to MINIMIZE downtime if a primary database fails?

A DevOps Engineer manages an application that has a cross-region failover requirement. The application stores its data in an Amazon Aurora on Amazon RDS database in the primary region with a read replica in the secondary region. The application uses Amazon Route 53 to direct customer traffic to the active region.

Which steps should be taken to MINIMIZE downtime if a primary database fails?
A . Use Amazon CloudWatch to monitor the status of the RDS instance. In the event of a failure, use a CloudWatch Events rule to send a short message service (SMS) to the Systems Operator using Amazon SNS. Have the Systems Operator redirect traffic to an Amazon S3 static website that displays a downtime message. Promote the RDS read replica to the master. Confirm that the application is working normally, then redirect traffic from the Amazon S3 website to the secondary region.
B. Use RDS Event Notification to publish status updates to an Amazon SNS topic. Use an AWS Lambda function subscribed to the topic to monitor database health. In the event of a failure, the Lambda function promotes the read replica, then updates Route 53 to redirect traffic from the primary region to the secondary region.
C. Set up an Amazon CloudWatch Events rule to periodically invoke an AWS Lambda function that checks the health of the primary database. If a failure is detected, the Lambda function promotes the read replica. Then, update Route 53 to redirect traffic from the primary to the secondary region.
D. Set up Route 53 to balance traffic between both regions equally. Enable the Aurora multi-master option, then set up a Route 53 health check to analyze the health of the databases. Configure Route 53 to automatically direct all traffic to the secondary region when a primary database fails.

View Answer

Answer: B

Explanation:

https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_Events.html