AWS Certified Advanced Networking – Specialty (ANS-C00) — Question 60

An application runs on a fleet of Amazon EC2 instances in a VPC. All instances can reach one another using private IP addresses. The application owner has a new requirement that the domain name received via DHCP should be different for a particular set of instances that are currently in one particular subnet.
What changes should be made to meet this requirement while continuing to support the existing application requirements?

Answer options

• A. Modify the existing DHCP option set and specify the different domain name for the specified subnet.
• B. Create a new DHCP option set with the different domain name, associate it with the specified subnet, and re-launch the Amazon EC2 instances.
• C. Create a new subnet, configure the DHCP option set with the different domain name, and re-launch the required instances there.
• D. Create a new peered VPC, configure the DHCP option set with the different domain name, and re-launch the required instances there.

Correct answer: B

Explanation

Creating a new DHCP option set and associating it with the specified subnet allows for the different domain name to be applied specifically to that subnet without affecting other instances. Modifying the existing DHCP option set (option A) would apply changes globally, which is not desired here. Options C and D suggest unnecessary complexity by creating new subnets or VPCs, which is not required to meet the specified needs.