What is the MOST effective way to accomplish these requirements?
Upload the licenses to a private Amazon S3 bucket. Create an AWS CloudFormation template with a Mappings section for the licenses. In the template, create an Auto Scaling group to launch the servers. In the user data script, acquire an available license from the Mappings section. Create an Auto Scaling lifecycle hook, then use it to update the mapping after the instance is terminated.
Upload the licenses to an Amazon DynamoDB table. Create an AWS CloudFormation template that uses an Auto Scaling group to launch the servers. In the user data script, acquire an available license from the DynamoDB table. Create an Auto Scaling lifecycle hook, then use it to update the mapping after the instance is terminated.
Upload the licenses to a private Amazon S3 bucket. Populate an Amazon SQS queue with the list of licenses stored in S3. Create an AWS CloudFormation template that uses an Auto Scaling group to launch the servers. In the user data script acquire an available license from SQS. Create an Auto Scaling lifecycle hook, then use it to put the license back in SQS after the instance is terminated.
Upload the licenses to an Amazon DynamoDB table. Create an AWS CLI script to launch the servers by using the parameter –count, with min:max instances to launch. In the user data script, acquire an available license from the DynamoDB table. Monitor each instance and, in case of failure, replace the instance, then manually update the DynamoDB table.
Explanations:
While this option suggests using an Auto Scaling group and a CloudFormation template, storing licenses in S3 without a mechanism for tracking availability leads to potential concurrency issues. Updating the mapping in Mappings section after termination is not a scalable solution for tracking available licenses.
This option effectively uses DynamoDB for tracking available licenses, allowing for atomic operations to check and update license availability as instances are launched and terminated. It provides a reliable mechanism to automate license management and scale efficiently, aligning well with the requirements.
Using SQS for license management can lead to issues, such as delayed processing or message visibility timeouts, making it less reliable than DynamoDB for real-time license availability. Additionally, returning licenses to SQS upon termination may introduce race conditions, complicating license tracking.
This option involves manual updates to the DynamoDB table, which introduces complexity and potential for errors. The reliance on CLI scripts and manual intervention to update the license status does not provide an automated or efficient solution to manage license availability at scale.
I evaluate that the answer is:
Upload the licenses to an Amazon DynamoDB table. Create an AWS CloudFormation template that uses an Auto Scaling group to launch the servers. In the user data script, acquire an available license from the DynamoDB table. Create an Auto Scaling lifecycle hook, then use it to update the mapping after the instance is terminated.