The answer is that route propagation is not enabled on the VPC route table. For a site-to-site VPN with dynamic routing using BGP, the VPC route table must have route propagation explicitly enabled to automatically inject the BGP-learned prefixes from the on-premises network. Without this setting, even though the VPN tunnel and BGP session are established, the routes are advertised but never installed into the VPC’s routing table. On the AWS Certified Advanced Networking Specialty ANS-C01 exam, this scenario tests your understanding of the critical distinction between establishing a BGP session and actually propagating those routes into the VPC—a common trap is assuming a healthy BGP session automatically populates routes. Remember the key step: enable route propagation on the VPC route table for dynamic VPNs, or the routes stay in the BGP table but never reach the VPC. Memory tip: “Propagation is the permission slip for BGP routes to enter the VPC route table.”
ANS-C01 Network Implementation Practice Question
This ANS-C01 practice question tests your understanding of network implementation. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A company is connecting their on-premises data center to AWS using a site-to-site VPN. The customer gateway device has a dynamic routing configuration with BGP. The VPN connection is established, but the VPC route table does not contain the on-premises network routes. What is the most likely cause?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "most likely"
Why it matters: Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Route propagation is not enabled on the VPC route table.
Option B is correct. For dynamic VPN, you must enable route propagation on the VPC route table to automatically propagate BGP routes. Option A is wrong because static routes are not needed. Option C is wrong because BGP is used. Option D is wrong because the customer gateway device is configured correctly.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✗
The customer gateway device is not configured with the correct BGP ASN.
Why it's wrong here
Incorrect ASN would prevent BGP session establishment, but the VPN is established.
✗
The VPC route table has static routes pointing to the virtual private gateway.
Why it's wrong here
Static routes would work but dynamic BGP requires propagation.
✓
Route propagation is not enabled on the VPC route table.
Why this is correct
Route propagation must be enabled for dynamic BGP routes to be added.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
✗
The VPN connection is using static routing instead of dynamic routing.
Common exam trap: answer the scenario, not the keyword
Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.
Detailed technical explanation
How to think about this question
This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.
KKey Concepts to Remember
Read the scenario before looking for a memorised answer.
Find the constraint that changes the correct option.
Eliminate answers that are true in general but not in this case.
Use explanations to understand the rule behind the answer.
TExam Day Tips
→Underline the problem statement mentally.
→Watch for words such as best, first, most likely and least administrative effort.
→Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A healthcare organisation deploys an application with a public-facing web tier and a private database tier. The database subnet has no public IP and only accepts connections from the web tier's security group. Questions like this test whether you can design cloud network isolation using VNets/VPCs, subnets, and security group rules.
What to study next
Got this wrong? Here's your next step.
Identify which ANS-C01 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
Network Implementation — This question tests Network Implementation — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Route propagation is not enabled on the VPC route table. — Option B is correct. For dynamic VPN, you must enable route propagation on the VPC route table to automatically propagate BGP routes. Option A is wrong because static routes are not needed. Option C is wrong because BGP is used. Option D is wrong because the customer gateway device is configured correctly.
What should I do if I get this ANS-C01 question wrong?
Identify which ANS-C01 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
Are there clue words in this question I should notice?
Yes — watch for: "most likely". Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. A company wants to connect its on-premises data center to a VPC using AWS Site-to-Site VPN. Which of the following is required to establish the VPN connection?
easy
A.Direct Connect gateway associated with the VPC
B.Internet gateway attached to the VPC
✓ C.Virtual private gateway attached to the VPC and a customer gateway representing the on-premises router
D.VPC endpoint for the VPN service
Why C: To establish a Site-to-Site VPN, you need a virtual private gateway (VGW) or transit gateway on the AWS side, and a customer gateway (CGW) representing the on-premises router. Option B is correct. Option A is incorrect because an internet gateway is used for public internet traffic, not VPN. Option C is incorrect because a Direct Connect gateway is for Direct Connect connections. Option D is incorrect because a VPC endpoint is for private access to AWS services.
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
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.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.