AWS Resource Type:
Amazon OpenSearch Reserved Instances (RIs)
Opportunity Description:
This Finder identifies fully utilized OpenSearch Reserved Instances (RIs) that are approaching expiration and recommends extending them to avoid falling back to on-demand pricing. Extending high-utilization RIs before expiration ensures sustained cost savings and prevents unexpected billing increases.
The Finder is especially useful for organizations managing multiple OpenSearch clusters across different regions and instance types — where manual tracking of reservations, utilization, and expiration windows is error-prone and time-consuming.
Criteria for identifying the opportunity:
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An OpenSearch RI is expiring within a configurable look-ahead window (default: 30 days).
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The RI has been fully utilized based on the previous 30-day usage history.
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Utilization is calculated using AWS Cost Explorer data.
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The number of currently running instances minus expiring reservations is less than total used instances, meaning those reservations are still needed.
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Only reservations that are safe to extend (100% utilized) are recommended.
Potential Savings (Annual Estimate):
Savings are estimated by comparing:
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The cost of running expiring instances at on-demand rates
vs. -
The cost of renewing the reservation with your preferred term (1-year or 3-year) and payment option (No Upfront, Partial, or All Upfront)
These savings are calculated per reservation and aggregated across all accounts and regions. The recommendation report includes a detailed breakdown.
What happens when the Fixer is executed?
This Finder does not perform any actions automatically. Instead, it generates:
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A per-reservation recommendation to extend (or not) based on usage patterns and expiration dates.
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Estimated annual cost savings for each recommended extension.
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Clear cost comparison tables for all available term and payment combinations.
You can use this data to manually extend reservations using the AWS Console or CLI.
Is it possible to roll back once CloudFix implements the Fixer?
Not applicable. CloudFix does not execute any changes. However, if you manually extend a reservation through AWS, that commitment is non-refundable.
Can CloudFix implement the fix automatically once I accept the recommendation?
No. This Finder is recommendation-only. It helps identify RIs worth extending but does not execute the reservation purchase.
Does the fix require downtime?
No. OpenSearch RIs affect billing, not performance or availability. Extending or not extending an RI does not cause service interruption.
Bill Gleeson
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