AWS Certified Advanced Networking – Specialty (ANS-C01) — Question 107

A company has 10 web server Amazon EC2 instances that run in an Auto Scaling group in a production VPC. The company has 10 other web servers that run in an on-premises data center. The company has a 10 Gbps AWS Direct Connect connection between the on-premises data center and the production VPC.

The company needs to implement a load balancing solution that receives HTTPS traffic from thousands of external users. The solution must distribute the traffic across the web servers on AWS and the web servers in the on-premises data center. Regardless of the location of the web servers, HTTPS requests must go to the same web server throughout the entire session.

Which solution will meet these requirements?

Answer options

• A. Create a Network Load Balancer (NLB) in the production VPC. Create a target group. Specify ip as the target type. Register the EC2 instances and the on-premises servers with the target group Enable connection draining on the NLB
• B. Create an Application Load Balancer (ALB) in the production VPC. Create a target group Specify ip as the target type. Register the EC2 instances and the on-premises servers with the target group. Enable application-based session affinity (sticky sessions) on the ALB.
• C. Create a Network Load Balancer (NLB) in the production VPCreate a target group. Specify instance as the target type. Register the EC2 instances and the on-premises servers with the target group. Enable session affinity (sticky sessions) on the NLB.
• D. Create an Application Load Balancer (ALB) in the production VPC. Create a target group. Specify instance as the target type Register the EC2 instances and the on-premises servers with the target group Enable application-based session affinity (sticky sessions) on the ALB.

Correct answer: B

Explanation

Option B is correct because an Application Load Balancer (ALB) supports application-based session affinity (sticky sessions), ensuring that the same web server handles requests for the duration of the session. Option A is incorrect because a Network Load Balancer does not support sticky sessions, and option C lacks the necessary session management for HTTPS traffic. Option D is incorrect because it specifies 'instance' as the target type, which is not suitable for including on-premises servers.