The template is working in us-east-1, but it is failing in us-west-2 with the error code:AMI [ami-12345678] does not existHow should the Administrator ensure that the AWS CloudFormation template is working in every region?
Copy the source region’s Amazon Machine Image (AMI) to the destination region and assign it the same ID.
Edit the AWS CloudFormation template to specify the region code as part of the fully qualified AMI ID.
Edit the AWS CloudFormation template to offer a drop-down list of all AMIs to the user by using the AWS::EC2::AMI::ImageID control.
Modify the AWS CloudFormation template by including the AMI IDs in the ג€Mappingsג€ section. Refer to the proper mapping within the template for the proper AMI ID.
Explanations:
AMI IDs are region-specific in AWS; copying an AMI to another region will assign it a new unique ID. The original ID will not be valid in the destination region, so this option does not solve the issue of making the template work in multiple regions.
While specifying the region code as part of the AMI ID could theoretically work, it is not a valid practice since AMI IDs are not constructed with region codes in their naming. AMI IDs must be explicitly defined for each region rather than being dynamically generated or formatted.
Using the AWS::EC2::AMI::ImageID control is not valid as there is no such resource type in CloudFormation that allows users to select AMIs dynamically. CloudFormation does not support dynamic selection of AMIs in the manner suggested here.
This option involves using the Mappings section of the CloudFormation template to define AMI IDs for different regions. This allows the template to refer to the appropriate AMI ID based on the region where it is being deployed, ensuring compatibility across regions.
As far as I’m aware, the answer is:
Modify the AWS CloudFormation template by including the AMI IDs in the ג€Mappingsג€ section. Refer to the proper mapping within the template for the proper AMI ID.