AWS CLF-C02: Billing, Pricing, and Support Practice Questions

AWS Pricing Calculator is the correct answer. It is a free web-based tool that lets you model your AWS architecture and get an estimated monthly cost before you deploy any resources — exactly what a new customer needs for pre-deployment cost estimation. AWS Cost Explorer is used to visualize and analyze spending on resources that are already running, not for pre-deployment estimates. AWS Budgets is used to set spending thresholds and receive alerts when costs approach or exceed those thresholds, not to estimate hypothetical costs. AWS Cost and Usage Report (CUR) provides detailed, line-item billing data for resources that have already incurred charges and is not a pre-deployment estimation tool.

This is expected and intended behavior. With consolidated billing in AWS Organizations, unused Reserved Instance capacity in one account is automatically applied to matching EC2 usage in other accounts within the same organization. This RI benefit sharing is a key advantage of consolidated billing — it maximizes RI utilization and savings across the entire organization without requiring any additional configuration. RI benefits are NOT restricted only to the purchasing account when consolidated billing is active; sharing is on by default (though it can be disabled per account). The idea that the management account is pocketing the discount is incorrect — all discounts are passed through to the member accounts that consume the matching usage. RI sharing does work across accounts in the same organization and is not limited by Region at the organizational level, though RIs themselves are Region-specific in terms of which instances they apply to.

Spot Instances are the most cost-effective option here. Spot Instances use spare AWS capacity and can be up to 90% cheaper than On-Demand pricing. Since the developer's workload is flexible in timing and can tolerate interruption (she has no fixed schedule), Spot Instances are ideal. On-Demand Instances are more expensive than Spot for flexible, interruptible workloads, though they would be fine for short-term unpredictable needs. Reserved Instances (even No Upfront) require a 1-year or 3-year commitment, making them poor value for just 8 hours of testing. Dedicated Hosts are the most expensive option, designed for use cases requiring dedicated physical hardware for licensing or compliance reasons — completely unsuitable for this cost-sensitive test scenario.

Business Support is the minimum plan that satisfies all three requirements. It provides: (1) Full access to all AWS Trusted Advisor checks (Basic and Developer only include the 7 core checks); (2) A response SLA of less than 1 hour for 'Production system down' (Severity 1) cases; and (3) Access to the AWS Support API, which allows programmatic case management. Basic Support has no Support Engineers, no full Trusted Advisor, and no Support API. Developer Support provides access to Cloud Support Engineers but only for non-production environments, does not include full Trusted Advisor, does not offer a sub-1-hour SLA, and does not include the Support API. Enterprise On-Ramp and Enterprise both meet all three requirements but are not the MINIMUM — Business is the least expensive plan to satisfy all conditions listed.

AWS Cost Explorer is correct because it provides an interactive interface to visualize, understand, and analyze AWS costs and usage over time, including built-in forecasting based on historical data. AWS Budgets is used to set spending or usage thresholds and receive alerts when those thresholds are breached—it monitors future spending rather than analyzing historical trends. AWS Cost and Usage Report (CUR) provides the most granular raw billing data in CSV/Parquet format but requires external tools (like Athena or QuickSight) to visualize and analyze—it is not purpose-built for interactive exploration. AWS Pricing Calculator is used to estimate the cost of planned AWS architectures before deploying them, not to analyze existing spending.