Difficulty: Easy
Description
These databases have had no connections in a month. Take a final snapshot, then delete them.
Selection Criteria
The maximum
DatabaseConnectionsmetric for the RDS instance has been less than 1 for the last 30 daysThe instance is not a read replica — replicas may show 0 connections even when actively used by the primary
⚠️ Warning — Aurora clusters: For Aurora, validate metrics at the individual instance level, not only at the cluster level, to avoid false positives
Expected Saving
Deleting an idle RDS instance eliminates 100% of its compute cost. Storage costs are also eliminated upon deletion.
Example: A db.t3.medium instance running 24/7:
Compute: $0.068/hr × 730 hrs/month = ~$49.64/month
Storage: 20 GB gp2 × $0.115/GB = ~$2.30/month
Total savings: ~$51.94/month per instance
Operational Impact
Downtime: Yes — deletion is irreversible. The instance and all its data are permanently deleted.
⚠️ WARNING — Data loss: Deleting an RDS instance without a final snapshot results in permanent, unrecoverable data loss. Always take a final snapshot before proceeding.
⚠️ WARNING — Final snapshot: The AWS Console offers a "Create final snapshot" option during deletion. This should always be enabled unless the data is confirmed as expendable.
⚠️ WARNING — Automated backups: Automated backups are deleted along with the instance unless "Retain automated backups" is explicitly enabled.
Recovery: Only possible if a snapshot was taken prior to deletion. Restore from the snapshot to recreate the instance — note that the new instance will have a different endpoint.