RDS Custom SQL Server Public and Private Access switching

Dear AWS Customer,

Hope you are in good health.

After going through the post, I understand that you would like to know if you can change the access from Public to Private for RDS custom database based on the requirement.

Please correct me if I misunderstood your query.

Answering your Query :

1. Can we switch/Change RDS Custom database Public and Private access types after creating RDS custom database ?

Ans : Yes, you can modify the RDS Custom DB after creation from Public access to Private access (vice-versa). Its completely possible. Please refer below steps :

AWS RDS Console -> Modify -> Connectivity -> Additional configuration -> Publicly accessible/Not Publicly accessible.

Kindly see the attached snapshots.

[+] https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/Overview.DBInstance.Modifying.html
[+] https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/working-with-custom-sqlserver.html

If you are looking for updating the access through VPC of the DB from DB Subnet groups , Please refer below document for more details :

[+] https://aws.amazon.com/premiumsupport/knowledge-center/rds-move-to-private-subnet/

For any technical queries while creation/modification of the DB instances, kindly create a Support ticket from below link :

[+] Creating support cases and case management - https://docs.aws.amazon.com/awssupport/latest/user/case-management.html

I hope the information provided above was helpful !

Have a great Day !