Which solution will meet these requirements MOST cost-effectively?
Purchase Scheduled Reserved Instances for the EC2 instances that run for only 12 hours on Sunday. Purchase Standard Reserved Instances for the EC2 instances that run constantly between Monday and Saturday.
Purchase Convertible Reserved Instances for the EC2 instances that run for only 12 hours on Sunday. Purchase Standard Reserved Instances for the EC2 instances that run constantly between Monday and Saturday.
Use Spot Instances for the EC2 instances that run for only 12 hours on Sunday. Purchase Standard Reserved Instances for the EC2 instances that run constantly between Monday and Saturday.
Use Spot Instances for the EC2 instances that run for only 12 hours on Sunday. Purchase Convertible Reserved Instances for the EC2 instances that run constantly between Monday and Saturday.
Explanations:
Scheduled Reserved Instances are ideal for predictable, scheduled workloads like the 12-hour Sunday usage. Standard Reserved Instances provide savings for the constant Monday-Saturday use.
Convertible Reserved Instances offer flexibility but are more costly than Scheduled Reserved Instances for predictable schedules. Not the most cost-effective for a known schedule.
Spot Instances are the least expensive but can be interrupted at any time, which doesn’t meet the requirement for uninterrupted Sunday operations.
Spot Instances again cannot guarantee uninterrupted operation on Sunday, and Convertible Reserved Instances are unnecessary for the stable, predictable Monday-Saturday schedule.
I opine that the answer is:
Purchase Scheduled Reserved Instances for the EC2 instances that run for only 12 hours on Sunday. Purchase Standard Reserved Instances for the EC2 instances that run constantly between Monday and Saturday.