AWS Certified Advanced Networking – Specialty (ANS-C00) — Question 45

You are designing the network infrastructure for an application server in Amazon VPC. Users will access all the application instances from the Internet and from an on-premises network. The on-premises network is connected to your VPC over an AWS Direct Connect link.
How should you design routing to meet these requirements?

Answer options

• A. Configure a single routing table with two default routes: one to the Internet via an IGW, the other to the on-premises network via the VGW. Use this routing table across all subnets in your VPC.
• B. Configure two routing tables: one that has a default route via the IGW, and another that has a default route via the VGW. Associate both routing tables with each VPC subnet.
• C. Configure a single routing table with a default route via the IGW. Propagate a default route via BGP on the AWS Direct Connect customer router. Associate the routing table with all VPC subnet.
• D. Configure a single routing table with a default route via the IGW. Propagate specific routes for the on-premises networks via BGP on the AWS Direct Connect customer router. Associate the routing table with all VPC subnets.

Correct answer: D

Explanation

The correct answer is D because it allows for specific routes to the on-premises network to be propagated, ensuring that traffic can properly route between the VPC and the on-premises network. Options A and B do not provide the necessary specificity for on-premises routing, while option C lacks the capability to route to the on-premises networks effectively.