AWS RDS retention period is more than specified in instance settings

Question

I have an AWS RDS instance with PostgreSQL. During instance creation, I had specified the maximum retention period of automated backup to be 7. But I can see automated backups of last 9 days in the snapshots section.

Does anyone have an idea what's going on here ?

Answer 1

This is quite normal. Please find below snippet from RDS FAQ

Q: Why do I have more automated DB snapshots than the number of days in the retention period for my DB instance?

It is normal to have 1 or 2 more automated DB snapshots than the number of days in your retention period. One extra automated snapshot is retained to ensure the ability to perform a point in time restore to any time during the retention period. For example, if your backup window is set to 1 day, you will require 2 automated snapshots to support restores to any within previous 24 hours. You may also see an additional automated snapshot as a new automated snapshot is always created before the oldest automated snapshot is deleted.

Answer 2

This is normal in RDS, you can see 1 or 2 more automated snapshots as compared to your max retention period. You can refer RDS docs for this. This is also provided in FAQ's https://aws.amazon.com/rds/faqs

For quick look please refer the FAQ screen shot ==> More no. of instances than retention period