AWS EC2 - Why Reserved Instances are not applied on Running On-Demand instances

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I need your help for one of the EC2 configuration changes I made recently.

I have 14 EC2 On-Demand running instances and sometime back I came to know that, I can actually reduce cost to half by purchasing reserved instances.

To begin with, I'd purchased 1 Reserved instance that matches with the On-Demand instance type and the billing discount applied immediately (I can confirm this based on this video: https://www.youtube.com/watch?v=rvdnJrLlWJs).

Then I went ahead and purchased 4 more Reserved Instances as shown below:

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After purchase I was expecting to see the billing discount applied but instead I saw RIs under No Region (show below). The configuration that I chose were exactly the same as I had for the single instance, the only difference here is the quantity of instances are 4.

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I can confirm that all of my 14 EC2 Running On-Demand instances are of t2.medium family.

Kindly help and suggest. Thanks

[UPDATE] Based on the approach @aws-ps suggested here's what I got:

Does not support vpc yet, please be careful when trusting these results
Does not support vpc yet, please be careful when trusting these results
Does not support vpc yet, please be careful when trusting these results
Does not support vpc yet, please be careful when trusting these results
Does not support vpc yet, please be careful when trusting these results
Does not support vpc yet, please be careful when trusting these results
Does not support vpc yet, please be careful when trusting these results
Does not support vpc yet, please be careful when trusting these results
Does not support vpc yet, please be careful when trusting these results
Does not support vpc yet, please be careful when trusting these results
Does not support vpc yet, please be careful when trusting these results
Does not support vpc yet, please be careful when trusting these results
Does not support vpc yet, please be careful when trusting these results
Does not support vpc yet, please be careful when trusting these results
Congratulations, you have no unused reservations

Congratulations, you have no unreserved instances
Traceback (most recent call last):
  File "./ec2-check-reserved-instances.py", line 84, in <module>
    qty_running_instances = reduce( lambda x, y: x+y, running_instances.values() )
TypeError: reduce() of empty sequence with no initial value
2

There are 2 answers

7
AWS PS On

I'd recommend using this script

https://github.com/epheph/ec2-check-reserved-instances

sometimes the billing is not reflected immediately but this tool helps me in confirm the RI setup

0
Puneet Pandey On

Got response from AWS. Here's what they said:

Have reviewed account and can confirm that the reserved are being successfully applied to the instances. You can confirm this by reviewing the Utilization report for the reserved instances in your Cost Explorer. Would, however, like to inform you that it may take upto 48 hours for the reservation utilization data to be available. - https://aws.amazon.com/aws-cost-management/reserved-instance-reporting/

You can also confirm that the Reserved instances are being applied to the instances by reviewing the line item that reads Amazon Elastic Compute Cloud running Linux/UNIX Reserved Instances. You will see that the usage for the reserved instances increases.