How should the Solutions Architect meet the CFO’s requirements while minimizing data loss?
In another region, configure a read replica and create a copy of the infrastructure. When an issue occurs, promote the read replica and configure as an Amazon RDS Multi-AZ database instance. Update the DNS record to point to the other region’s ELB.
Configure a 1-day window of 60-minute snapshots of the Amazon RDS Multi-AZ database instance. Create an AWS CloudFormation template of the application infrastructure that uses the latest snapshot. When an issue occurs, use the AWS CloudFormation template to create the environment in another region. Update the DNS record to point to the other region’s ELB.
Configure a 1-day window of 60-minute snapshots of the Amazon RDS Multi-AZ database instance which is copied to another region. Create an AWS CloudFormation template of the application infrastructure that uses the latest copied snapshot. When an issue occurs, use the AWS CloudFormation template to create the environment in another region. Update the DNS record to point to the other region’s ELB.
Configure a read replica in another region. Create an AWS CloudFormation template of the application infrastructure. When an issue occurs, promote the read replica and configure as an Amazon RDS Multi-AZ database instance and use the AWS CloudFormation template to create the environment in another region using the promoted Amazon RDS instance. Update the DNS record to point to the other region’s ELB.
Explanations:
Promoting the read replica and updating the DNS to point to the other region’s ELB can help reduce downtime, but it doesn’t minimize data loss as the read replica may lag behind. Additionally, read replicas are intended for scaling, not disaster recovery.
Creating hourly snapshots and using CloudFormation for re-creating infrastructure in another region doesn’t meet the two-hour recovery time objective and introduces unnecessary complexity. The time to deploy new infrastructure might exceed the acceptable downtime.
Although snapshots are copied to another region, restoring the infrastructure using CloudFormation still does not guarantee meeting the two-hour recovery time objective. The downtime may exceed two hours due to the time needed to create the new environment.
Configuring a read replica in another region and using CloudFormation to create infrastructure in the new region ensures minimal downtime. When promoted, the read replica will be up-to-date with minimal data loss. This approach meets the recovery time and minimizes impact.
If I had to guess, I’d say the answer is:
Configure a read replica in another region. Create an AWS CloudFormation template of the application infrastructure. When an issue occurs, promote the read replica and configure as an Amazon RDS Multi-AZ database instance and use the AWS CloudFormation template to create the environment in another region using the promoted Amazon RDS instance. Update the DNS record to point to the other region’s ELB.