AWS Certified Solutions Architect – Professional SAP-C01 – Question270

A user is hosting a public website on AWS. The user wants to have the database and the app server on the AWS VPC. The user wants to setup a database that can connect to the Internet for any patch upgrade but cannot receive any request from the internet. How can the user set this up?

A. Setup DB in a private subnet with the security group allowing only outbound traffic.
B. Setup DB in a public subnet with the security group allowing only inbound data.
C. Setup DB in a local data center and use a private gateway to connect the application with DB.
D. Setup DB in a private subnet which is connected to the internet via NAT for outbound.

Correct Answer: D

Explanation:

Explanation: A Virtual Private Cloud (VPC) is a virtual network dedicated to the user’s AWS account. It enables the user to launch AWS resources into a virtual network that the user has defined. AWS provides two features that the user can use to increase security in VPC: security groups and network ACLs. When the user wants to setup both the DB and App on VPC, the user should make one public and one private subnet. The DB should be hosted in a private subnet and instances in that subnet cannot reach the internet. The user can allow an instance in his VPC to initiate outbound connections to the internet but prevent unsolicited inbound connections from the internet by using a Network Address Translation (NAT) instance.
Reference:
http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_Subnets.html