AWS Certified Cloud Practitioner

Explanation

Correct Answer: C - Add cost allocation tags to each EC2 instance. Activate the tags.

Why this is the most operationally efficient solution:

1. AWS Cost Allocation Tags: AWS provides built-in cost allocation tagging that allows you to categorize and track your AWS costs at a granular level. By adding tags to EC2 instances (such as Environment=Production, Project=WorkloadA, Department=Marketing), you can easily identify costs associated with specific workloads.

2. Minimal Operational Overhead:

   • Option A (separate accounts) would require significant administrative overhead to create and manage multiple AWS accounts, plus the complexity of cross-account resource management.
   • Option B (different instance families) doesn't inherently provide cost tracking and could lead to inefficient resource utilization.
   • Option D (custom database) requires developing, maintaining, and operating a custom solution, which is much more complex and error-prone.

3. Native AWS Integration: Cost allocation tags integrate directly with AWS Cost Explorer, AWS Budgets, and AWS Cost and Usage Reports, providing comprehensive cost analysis capabilities without additional infrastructure.

4. Activation Requirement: After creating tags, you must activate them in the AWS Billing and Cost Management console to include them in cost allocation reports.

Implementation Steps:

1. Add relevant tags to EC2 instances (e.g., Workload=Analytics, Workload=WebApp)
2. Activate the tags in AWS Billing console
3. Use AWS Cost Explorer to analyze costs by tag
4. Set up budgets and alerts based on tagged resources

This approach provides the most efficient way to track workload-specific costs while leveraging AWS's native cost management capabilities.