Which solution will meet these requirements with the LEAST operational overhead?
Replace the ALB with a Network Load Balancer. Maintain the embedded NoSQL database with its replication service on the EC2 instances.
Replace the ALB with a Network Load Balancer. Migrate the embedded NoSQL database to Amazon DynamoDB by using AWS Database Migration Service (AWS DMS).
Modify the Auto Scaling group to use EC2 instances across three Availability Zones. Maintain the embedded NoSQL database with its replication service on the EC2 instances.
Modify the Auto Scaling group to use EC2 instances across three Availability Zones. Migrate the embedded NoSQL database to Amazon DynamoDB by using AWS Database Migration Service (AWS DMS).
Explanations:
Replacing the ALB with a Network Load Balancer does not address the high availability requirement, as the application would still be limited to a single Availability Zone, resulting in potential downtime if that zone fails. Maintaining the embedded NoSQL database adds operational overhead as the replication service must be managed.
While migrating to DynamoDB would reduce operational overhead by utilizing a managed service, replacing the ALB with a Network Load Balancer does not improve availability since it still relies on a single Availability Zone. This option fails to meet the high availability requirement.
Modifying the Auto Scaling group to use EC2 instances across three Availability Zones improves availability, but maintaining the embedded NoSQL database still requires operational overhead for managing replication and ensuring eventual consistency across instances.
This option meets the requirement for high availability by using EC2 instances across three Availability Zones, and migrating to Amazon DynamoDB reduces operational overhead by leveraging a managed NoSQL service, ensuring eventual consistency and eliminating the need to manage the database infrastructure.
I map out that the answer is:
Modify the Auto Scaling group to use EC2 instances across three Availability Zones. Migrate the embedded NoSQL database to Amazon DynamoDB by using AWS Database Migration Service (AWS DMS).