- A
Apply an NSG to SubnetA with inbound rules allowing HTTP/HTTPS from Internet, and apply a separate NSG to SubnetB with inbound rules allowing only traffic from SubnetA.
Separate NSGs provide clear isolation and are efficient.
- B
Apply one NSG to both subnets with rules allowing HTTP/HTTPS from internet, and allow traffic from SubnetA to SubnetB.
Why wrong: A single NSG applied to both subnets would allow internet traffic into SubnetB if not explicitly denied, which is not efficient.
- C
Use application security groups (ASGs) on the web servers and application servers, and configure NSG rules referencing the ASGs.
Why wrong: ASGs are useful for grouping VMs but not required; separate NSGs per subnet are simpler.
- D
Deploy Azure Firewall in the virtual network and configure application rules to allow HTTP/HTTPS to SubnetA and traffic to SubnetB.
Why wrong: Azure Firewall is more complex and costly than NSGs for this simple requirement.
Quick Answer
The answer is to apply an NSG to SubnetA with inbound rules allowing HTTP and HTTPS from the Internet, and a separate NSG to SubnetB with an inbound rule allowing only traffic from SubnetA. This configuration is correct because network security groups (NSGs) act as stateful, distributed firewalls at the subnet or NIC level, and by attaching distinct NSGs to each subnet you can precisely control east-west traffic flow between subnets while maintaining a default deny rule for all other inbound traffic. On the Microsoft Azure Security Engineer Associate AZ-500 exam, this scenario tests your understanding of NSG rule priority and the principle of least privilege—a common trap is assuming a single NSG applied to the whole VNet can differentiate between subnets, or confusing application security groups (ASGs) which group VMs but do not filter traffic themselves. Remember the memory tip: "SubnetA gets the web, SubnetB gets the app, and only SubnetA can tap."
AZ-500 Secure networking Practice Question
This AZ-500 practice question tests your understanding of secure networking. 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.
You have an Azure virtual network (VNet1) with two subnets: SubnetA and SubnetB. SubnetA hosts web servers that must be accessible from the internet. SubnetB hosts application servers that should only be accessible from SubnetA. You need to configure network security groups (NSGs) to enforce this traffic flow. The solution must allow HTTP and HTTPS traffic from the internet to SubnetA, and allow only traffic from SubnetA to SubnetB. All other inbound traffic should be denied. What is the most efficient way to configure the NSGs?
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
Apply an NSG to SubnetA with inbound rules allowing HTTP/HTTPS from Internet, and apply a separate NSG to SubnetB with inbound rules allowing only traffic from SubnetA.
Option B is correct. Apply an NSG to SubnetA with rules allowing HTTP/HTTPS from internet and deny all other inbound. Apply an NSG to SubnetB with a rule allowing traffic from SubnetA and deny all other inbound. This is efficient and meets requirements. Option A is inefficient because rules on SubnetB would still allow traffic from internet if not denied. Option C is incorrect because ASGs alone don't filter traffic. Option D is incorrect because Azure Firewall is overkill.
Key principle: Count usable hosts — not total addresses — and remember that the network and broadcast addresses are not available to hosts in standard IPv4 subnets.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Apply an NSG to SubnetA with inbound rules allowing HTTP/HTTPS from Internet, and apply a separate NSG to SubnetB with inbound rules allowing only traffic from SubnetA.
Why this is correct
Separate NSGs provide clear isolation and are efficient.
Related concept
CIDR notation defines the prefix length.
- ✗
Apply one NSG to both subnets with rules allowing HTTP/HTTPS from internet, and allow traffic from SubnetA to SubnetB.
Why it's wrong here
A single NSG applied to both subnets would allow internet traffic into SubnetB if not explicitly denied, which is not efficient.
- ✗
Use application security groups (ASGs) on the web servers and application servers, and configure NSG rules referencing the ASGs.
Why it's wrong here
ASGs are useful for grouping VMs but not required; separate NSGs per subnet are simpler.
- ✗
Deploy Azure Firewall in the virtual network and configure application rules to allow HTTP/HTTPS to SubnetA and traffic to SubnetB.
Why it's wrong here
Azure Firewall is more complex and costly than NSGs for this simple requirement.
Common exam traps
Common exam trap: usable hosts are not the same as total addresses
Subnetting questions often tempt you into counting all addresses. In normal IPv4 subnets, the network and broadcast addresses are not usable host addresses.
Detailed technical explanation
How to think about this question
Subnetting questions test whether you can identify the network, broadcast address, usable range, mask and correct subnet. Slow down enough to calculate the block size correctly.
KKey Concepts to Remember
- CIDR notation defines the prefix length.
- Block size helps identify subnet boundaries.
- Network and broadcast addresses are not usable hosts in normal IPv4 subnets.
- The required host count determines the smallest suitable subnet.
TExam Day Tips
- Write the block size before choosing the subnet.
- Check whether the question asks for hosts, subnets or a specific address range.
- Do not confuse /24, /25, /26 and /27 host counts.
Key takeaway
Count usable hosts — not total addresses — and remember that the network and broadcast addresses are not available to hosts in standard IPv4 subnets.
Real-world example
How this comes up in practice
A company's IT admin needs to give a contractor read-only access to production logs without sharing account credentials. Using role-based access control (RBAC) and temporary scoped permissions — not a permanent shared password — is the correct pattern. Questions like this test whether you can apply least-privilege access across cloud identity services.
What to study next
Got this wrong? Here's your next step.
Review block sizes, usable host formulas (2^n − 2), and how to find network and broadcast addresses for /24 through /30. Then practise related AZ-500 subnetting questions on CIDR, address ranges, and subnet selection.
- →
Secure networking — study guide chapter
Learn the concepts, then practise the questions
- →
Secure networking practice questions
Targeted practice on this topic area only
- →
All AZ-500 questions
1,000 questions across all exam domains
- →
Microsoft Azure Security Engineer Associate AZ-500 study guide
Full concept coverage aligned to exam objectives
- →
AZ-500 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related AZ-500 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Secure identity and access practice questions
Practise AZ-500 questions linked to Secure identity and access.
Secure compute, storage, and databases practice questions
Practise AZ-500 questions linked to Secure compute, storage, and databases.
Secure Azure using Microsoft Defender for Cloud and Microsoft Sentinel practice questions
Practise AZ-500 questions linked to Secure Azure using Microsoft Defender for Cloud and Microsoft Sentinel.
Manage identity and access practice questions
Practise AZ-500 questions linked to Manage identity and access.
Secure networking practice questions
Practise AZ-500 questions linked to Secure networking.
AZ-500 fundamentals practice questions
Practise AZ-500 questions linked to AZ-500 fundamentals.
AZ-500 scenario practice questions
Practise AZ-500 questions linked to AZ-500 scenario.
AZ-500 troubleshooting practice questions
Practise AZ-500 questions linked to AZ-500 troubleshooting.
Practice this exam
Start a free AZ-500 practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this AZ-500 question test?
Secure networking — This question tests Secure networking — CIDR notation defines the prefix length..
What is the correct answer to this question?
The correct answer is: Apply an NSG to SubnetA with inbound rules allowing HTTP/HTTPS from Internet, and apply a separate NSG to SubnetB with inbound rules allowing only traffic from SubnetA. — Option B is correct. Apply an NSG to SubnetA with rules allowing HTTP/HTTPS from internet and deny all other inbound. Apply an NSG to SubnetB with a rule allowing traffic from SubnetA and deny all other inbound. This is efficient and meets requirements. Option A is inefficient because rules on SubnetB would still allow traffic from internet if not denied. Option C is incorrect because ASGs alone don't filter traffic. Option D is incorrect because Azure Firewall is overkill.
What should I do if I get this AZ-500 question wrong?
Review block sizes, usable host formulas (2^n − 2), and how to find network and broadcast addresses for /24 through /30. Then practise related AZ-500 subnetting questions on CIDR, address ranges, and subnet selection.
What is the key concept behind this question?
CIDR notation defines the prefix length.
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 →
Keep practising
More AZ-500 practice questions
- A public web application should be protected from OWASP-style attacks and network-layer DDoS attacks. Which two Azure se…
- A security analyst uses Microsoft Defender for Cloud. They want to view a list of all security recommendations for their…
- A company uses Azure AD B2B collaboration to invite external vendors. They want to restrict the vendors to only be able…
- A company uses Defender for Servers Plan 2. Which two capabilities are included compared with a basic posture-only confi…
- A Sentinel detection should enrich alerts with business-critical asset context. Which two mechanisms are appropriate?
- A company uses Microsoft Defender for Cloud to manage its security posture. The compliance team wants to monitor the sub…
Last reviewed: Jun 20, 2026
This AZ-500 practice question is part of Courseiva's free Microsoft 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 AZ-500 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.