AWS Certified Solutions Architect – Associate (SAA-C02) — Question 278

A company needs guaranteed Amazon EC2 capacity in three specific Availability Zones in a specific AWS Region for an upcoming event that will last 1 week.
What should the company do to guarantee the EC2 capacity?

Answer options

• A. Purchase Reserved Instances that specify the Region needed.
• B. Create an On-Demand Capacity Reservation that specifies the Region needed.
• C. Purchase Reserved Instances that specify the Region and three Availability Zones needed.
• D. Create an On-Demand Capacity Reservation that specifies the Region and three Availability Zones needed.

Correct answer: D

Explanation

On-Demand Capacity Reservations enable you to reserve compute capacity for Amazon EC2 instances in a specific Availability Zone for any duration, which fits the 1-week requirement perfectly. Reserved Instances require a minimum commitment of 1 or 3 years, making them unsuitable and cost-ineffective for a short-term event. Furthermore, capacity reservations must specify both the Region and the exact Availability Zones to guarantee capacity where needed.