AWS Certified SysOps Administrator – Associate (legacy) — Question 528

A SysOps Administrator has created an Amazon EC2 instance using an AWS CloudFormation template in the us-east-1 Region. The Administrator finds that this template has failed to create an EC2 instance in the us-west-2 Region.
What is one cause for this failure?

Answer options

• A. Resource tags defined in the CloudFormation template are specific to the us-east-1 Region.
• B. The Amazon Machine Image (AMI) ID referenced in the CloudFormation template could not be found in the us-west-2 Region.
• C. The cfn-init script did not run during resource provisioning in the us-west-2 Region.
• D. The IAM user was not created in the specified Region.

Correct answer: B

Explanation

Amazon Machine Image (AMI) IDs are unique to each AWS Region, meaning an AMI ID valid in us-east-1 will not exist in us-west-2. When a CloudFormation template hardcodes an AMI ID, it cannot be deployed in other regions unless a mapping is used to dynamically select the correct region-specific AMI ID. Other options are incorrect because IAM users are global, resource tags are not region-specific, and a cfn-init failure would not prevent the EC2 resource creation itself from initiating.