AWS Certified Cloud Practitioner (CLF-C02)Cloud Technology and ServicesEasy
A logistics company runs a fleet of EC2 instances that support a core inventory-management application 24/7 with no planned interruptions for the next three years. The company wants to minimize compute costs for this steady, predictable workload. Which EC2 purchasing option should the company choose?
- ASpot Instances
- BReserved Instances
- CDedicated Hosts
- DOn-Demand Instances
Show answer & explanationAnswer & explanation
Correct answer: B. Reserved Instances
Reserved Instances provide a significant discount (up to 72% compared to On-Demand) in exchange for a 1- or 3-year commitment, making them ideal for steady-state, predictable workloads that run continuously.
Why the other options are wrong
- A. Spot Instances can be interrupted and are unsuitable for a 24/7 core application.
- C. Dedicated Hosts are for compliance/licensing needs requiring physical server visibility, not cost optimization for standard workloads.
- D. On-Demand costs more per hour and is best for unpredictable or short-term workloads.
EC2 Reserved Instances
A pricing model that offers significant discounts on EC2 usage in exchange for a 1- or 3-year commitment to a specific instance configuration.
- Up to 72% cheaper than On-Demand
- Best for steady-state, predictable workloads
- Standard, Convertible, and Scheduled RI types available
Memory trick: 'Reserve now, save later' for workloads that never stop.