ANS-C01 Network Design Practice Question
A company is expanding its on-premises network to AWS using Direct Connect and VPN backup. They have two Direct Connect connections from different providers to two different Direct Connect locations in the same region. They have configured a private virtual interface (VIF) on each connection to a virtual private gateway (VGW) attached to a VPC. They have also configured a VPN connection as a backup. The company uses BGP to advertise the on-premises prefixes to AWS. They want to ensure that traffic is load-balanced across both Direct Connect connections under normal conditions and that the VPN is used only if both Direct Connect connections fail. They also want to minimize the cost of data transfer. Which BGP configuration should they use?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Advertise the same prefixes over both Direct Connect connections with equal local preference, and prepend AS path on the VPN routes to make them less preferred
By advertising the same prefixes over both Direct Connect connections with equal local preference, traffic is load-balanced across both connections under normal conditions. AS path prepending on VPN routes makes the VPN less preferred than Direct Connect, so the VPN is used only when both Direct Connect connections fail. This configuration also minimizes cost by preferring Direct Connect over VPN. Option A is incorrect because a single BGP session over one Direct Connect connection creates a single point of failure. Option C is incorrect because setting a higher MED on one Direct Connect connection makes it less preferred, resulting in active/passive rather than load-balanced traffic. Option D is incorrect because advertising different prefixes over each connection does not load-balance traffic; it routes different destinations through each connection.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Configure a single BGP session over both Direct Connect connections using the same virtual interface
Why it's wrong here
Single BGP session does not provide redundancy.
- ✓
Advertise the same prefixes over both Direct Connect connections with equal local preference, and prepend AS path on the VPN routes to make them less preferred
Why this is correct
Equal local preference allows load balancing; AS path prepending makes VPN less preferred.
- ✗
Set a higher MED on one of the Direct Connect connections to make it the primary, and use the VPN as secondary
Why it's wrong here
Higher MED makes one path less preferred, not load-balanced.
- ✗
Advertise different on-premises prefixes over each Direct Connect connection and use the VPN for all traffic
Why it's wrong here
Different prefixes would not load-balance; VPN should be backup only.
Go deeper
Related to this question
About these practice questions
Courseiva writes every ANS-C01 question from scratch — 1,621 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This ANS-C01 practice question is part of Courseiva's free Amazon Web Services certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the ANS-C01 exam.