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- Standard Reserved Instances
- Apply to a single instance family, platform, scope, and tenancy over a term
- One or three year term
- Can reserve capacity (locked into one availability zone) or be regional (can launch in any AZ within the region)
- Greatest discount
- Convertible Reserved Instances
- They allow you to change the instance family and other parameters associated with a Reserved Instance at any time. For example, you can convert C3 RIs to C4 RIs to take advantage of a newer instance type, or convert C4 RIs to M4 RIs if your application turns out to need more memory.
- Three year term
- Can reserve capacity (locked into one availability zone) or be regional (can launch in any AZ within the region)
- Slightly more expensive than standard
Scheduled Instances
- One year term
- Repeating schedule (daily, weekly, monthly)
- http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-scheduled-instances.html
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