Which solution will meet these requirements with the LEAST implementation effort?
Run Amazon EC2 On-Demand Instances in an Auto Scaling group for the web portal. Use an AWS Lambda function to run the document extract program. Invoke the Lambda function when an employee uploads a new reimbursement document.
Run Amazon EC2 Spot Instances in an Auto Scaling group for the web portal. Run the document extract program on EC2 Spot Instances. Start document extract program instances when an employee uploads a new reimbursement document.
Purchase a Savings Plan to run the web portal and the document extract program. Run the web portal and the document extract program in an Auto Scaling group.
Create an Amazon S3 bucket to host the web portal. Use Amazon API Gateway and an AWS Lambda function for the existing functionalities. Use the Lambda function to run the document extract program. Invoke the Lambda function when the API that is associated with a new document upload is called.
Explanations:
Running the web portal on Amazon EC2 On-Demand Instances ensures high availability, and using AWS Lambda for document extraction reduces cost and scales automatically. Lambda runs only on demand and requires minimal implementation changes.
Spot Instances are not suitable for the web portal because they do not guarantee availability, which is required for a system that needs 100% uptime. Additionally, Spot Instances can be interrupted, impacting document processing reliability.
A Savings Plan can reduce costs, but running both the web portal and document extract program on EC2 could lead to unnecessary expenses and maintenance overhead. Also, this setup does not offer the same level of scalability as Lambda.
Hosting the web portal on S3 with API Gateway and Lambda would require extensive changes to the current setup, violating the requirement for minimal implementation changes. This setup would require significant reconfiguration efforts.