为什么我的 AWS RDS 备份的保留时间比配置的时间长？
Why are my AWS RDS backups being retained longer than configured?
我已将 RDS 配置为保留备份（快照）1 天，但我总是看到保留了 3 天的备份。为什么？
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.
我已将 RDS 配置为保留备份（快照）1 天，但我总是看到保留了 3 天的备份。为什么？
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.