Which EC2 instance purchasing option will meet these requirements MOST cost-effectively?
On-Demand Instances
Reserved Instances
Spot Instances
Spot Fleet
Explanations:
On-Demand Instances are flexible but more expensive for long-term use compared to Reserved Instances. They are not the most cost-effective for a year of consistent usage.
Reserved Instances provide a significant discount for committing to a one-year term, making them the most cost-effective option for predictable traffic and availability.
Spot Instances are cheaper but can be interrupted by AWS with little notice, which does not align with the requirement for consistent availability.
Spot Fleet also relies on Spot Instances and shares the same risk of interruption, making it unsuitable for the need for continuous availability.