AWS Certified Solutions Architect – Professional — Question 189

An organization is setting up a highly scalable application using Elastic Beanstalk. The organization is using ELB and RDS with VPC. The organization has public and private subnets within the cloud.
Which of the below mentioned configurations will not work in this scenario?

Answer options

• A. To setup RDS in a private subnet and ELB in a public subnet.
• B. The configuration must have public and private subnets in the same AZ.
• C. The configuration must have two private subnets in separate AZs.
• D. The EC2 instance should have a public IP assigned to it.

Correct answer: D

Explanation

Option D is correct because in a typical architecture using ELB and RDS, EC2 instances in private subnets do not require public IPs to communicate with ELB, which acts as a bridge to the internet. Options A, B, and C are valid configurations that align with best practices for high availability and security in a VPC setup.