Are My RDS DB Instances Available When Scaling?

Currently, you can scale up storage space and change the CPU or memory of a DB instance.

• When storage space is being scaled up, RDS DB instances are still available and services are not affected. However, you cannot delete or reboot DB instances that are being scaled.
• When the CPU or memory of DB instances is being changed, the network is intermittently disconnected once or twice within a few seconds. (For Microsoft SQL Server 2017 Enterprise Edition, you need to stop services first and then change the CPU or memory of DB instances.) For primary/standby DB instances, a failover may occur and services may be briefly interrupted. Changing the CPU or memory takes 5 to 15 minutes.

  After you change the CPU or memory, the DB instances will reboot and services will be interrupted. Therefore, you are advised to change instance classes during off-peak hours.