The answer is 10.22.0.0/16, a completely separate Class A private range that avoids overlap with both the hub VNet (10.20.0.0/16) and the on-premises network (10.21.0.0/16). This is correct because Azure VNet peering and hybrid connectivity require non-overlapping address spaces to prevent routing conflicts; if any two connected networks share the same IP range, Azure cannot determine where to send traffic, causing failures in peering or VPN/ExpressRoute connections. On the AZ-104 exam, this scenario tests your understanding of how to choose a non-overlapping address space for VNet peering, often presented as a spoke-to-hub topology with future on-premises connectivity. The common trap is selecting a subnet within the hub’s or on-premises range (e.g., 10.20.0.0/24), which would create a hidden overlap. A reliable memory tip: think of the hub, on-prem, and spoke as three separate floors in a building—each needs its own unique floor number (a distinct /16) to avoid mail being delivered to the wrong address.
AZ-104 Implement and Manage Virtual Networking Practice Question
This AZ-104 practice question tests your understanding of implement and manage virtual networking. Match the stated requirement to the specific cloud service, access model, or configuration option — many options are valid in isolation but not for this scenario. 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 already uses the address space 10.20.0.0/16 for a hub virtual network and 10.21.0.0/16 on-premises. A new spoke virtual network will be peered to the hub and may later connect to the on-premises network. Which address space should the administrator choose for the spoke to avoid future routing conflicts?
Why wrong: This range still falls inside the hub VNet address space, so it would overlap immediately.
B
10.21.0.0/16
Why wrong: This range conflicts with the existing on-premises network, which would complicate peering and routing.
C
10.22.0.0/16
This range does not overlap with either the hub VNet or the on-premises network. It also provides a full /16, which leaves enough room for multiple subnets and future growth while keeping peering and hybrid connectivity straightforward.
D
10.20.128.0/17
Why wrong: This prefix is also within the hub VNet range, so it would overlap with the existing address space.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
10.22.0.0/16
Option C (10.22.0.0/16) is correct because it is a unique, non-overlapping address space that does not conflict with the existing hub VNet (10.20.0.0/16) or the on-premises network (10.21.0.0/16). When a spoke VNet is peered to the hub and later connected to on-premises via VPN or ExpressRoute, Azure requires that all peered and connected address spaces be unique to avoid routing conflicts. Choosing a completely separate /16 ensures no future overlap.
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.
✗
10.20.64.0/19
Why it's wrong here
This range still falls inside the hub VNet address space, so it would overlap immediately.
✗
10.21.0.0/16
Why it's wrong here
This range conflicts with the existing on-premises network, which would complicate peering and routing.
✓
10.22.0.0/16
Why this is correct
This range does not overlap with either the hub VNet or the on-premises network. It also provides a full /16, which leaves enough room for multiple subnets and future growth while keeping peering and hybrid connectivity straightforward.
Related concept
Read the scenario before looking for a memorised answer.
✗
10.20.128.0/17
Why it's wrong here
This prefix is also within the hub VNet range, so it would overlap with the existing address space.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often assume any address space outside the hub's /16 is safe, but they forget to check for overlap with the on-premises network (10.21.0.0/16) or incorrectly think that a smaller subnet within the hub's range (like 10.20.64.0/19) can be used if it is not currently in use, ignoring that Azure requires completely non-overlapping ranges for peered VNets.
Detailed technical explanation
How to think about this question
Azure VNet peering enforces that peered VNets must have non-overlapping address spaces; overlapping ranges cause peering to fail with a 'conflicting address space' error. When a spoke VNet is later connected to on-premises via a gateway (e.g., in a hub-and-spoke topology), Azure uses the effective routes table, and overlapping prefixes (e.g., 10.21.0.0/16) would result in asymmetric routing or dropped traffic because the on-premises route and the spoke route would have equal or conflicting precedence. The recommended practice is to reserve a contiguous, non-overlapping block (like 10.22.0.0/16) for future spokes to simplify network design and avoid re-IP efforts.
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.
TExam Day Tips
→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.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this AZ-104 question in full detail.
Implement and Manage Virtual Networking — This question tests Implement and Manage Virtual Networking — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: 10.22.0.0/16 — Option C (10.22.0.0/16) is correct because it is a unique, non-overlapping address space that does not conflict with the existing hub VNet (10.20.0.0/16) or the on-premises network (10.21.0.0/16). When a spoke VNet is peered to the hub and later connected to on-premises via VPN or ExpressRoute, Azure requires that all peered and connected address spaces be unique to avoid routing conflicts. Choosing a completely separate /16 ensures no future overlap.
What should I do if I get this AZ-104 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
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. Based on the exhibit, which address space can you assign to the new spoke virtual network so it can be peered to the hub and later connected to on-premises without an IP overlap?
medium
A.10.50.128.0/17
B.10.51.0.0/16
✓ C.10.52.0.0/16
D.10.50.0.0/24
Why C: Option C (10.52.0.0/16) is correct because it does not overlap with the hub virtual network's address space (10.50.0.0/16) or the on-premises network (10.51.0.0/16). This allows the spoke VNet to be peered to the hub and later connected to on-premises via a gateway in the hub without IP address conflicts, which is a requirement for successful VNet peering and VPN/ExpressRoute connectivity.
Last reviewed: Jun 11, 2026
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.
This AZ-104 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-104 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.