Which solution will meet these requirements MOST cost-effectively?
Deploy EC2 instances in an additional Region. Create a DB instance with the Multi-AZ option activated.
Deploy all EC2 instances in the same Region and the same Availability Zone. Create a DB instance with the Multi-AZ option activated.
Deploy EC2 instances across at least two Availability Zones within the same Region. Create a DB instance in a single Availability Zone.
Deploy EC2 instances across at least two Availability Zones within the same Region. Create a DB instance with the Multi-AZ option activated.
Explanations:
Deploying EC2 instances in an additional Region increases complexity and cost without ensuring high availability for the application within a single Region. A Multi-AZ RDS instance alone does not address the EC2 component’s availability across Regions.
Deploying all EC2 instances in the same Availability Zone does not provide high availability. If that Availability Zone fails, both EC2 and RDS will become unavailable, which undermines the goal of high availability. Multi-AZ for RDS helps but is not sufficient alone for the EC2 instances.
While deploying EC2 instances across two Availability Zones improves availability, having the RDS instance in a single Availability Zone does not ensure database high availability. If that AZ fails, the database will also be unavailable, compromising the application’s reliability.
Deploying EC2 instances across at least two Availability Zones ensures that if one zone fails, the application can continue running in the other zone. Additionally, using a Multi-AZ RDS instance provides redundancy for the database, ensuring high availability for both application layers.
I sort that the answer is:
Deploy EC2 instances across at least two Availability Zones within the same Region. Create a DB instance with the Multi-AZ option activated.