The answer is two Cloud NAT gateways, one per region. This is correct because Cloud NAT is a regional resource, not a global one; each gateway is configured within a specific region and only provides outbound internet access to VMs in that region’s subnets. Since the VPC spans us-central1 and europe-west1, a separate Cloud NAT gateway must be deployed in each region to cover both sets of VMs. On the Google Professional Cloud Network Engineer exam, this question tests your understanding of Cloud NAT’s regional scope—a common trap is assuming a single gateway can serve multiple regions, but Cloud NAT does not support cross-region functionality. A helpful memory tip: think of Cloud NAT as a regional “exit door”—each region needs its own door for VMs to reach the internet.
PCNE Implementing a Virtual Private Cloud Practice Question
This PCNE practice question tests your understanding of implementing a virtual private cloud. 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 has a VPC with subnets in us-central1 and europe-west1. They want to deploy a Cloud NAT to allow VMs in both regions to access the internet. How many Cloud NAT gateways are needed?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Two Cloud NAT gateways, one per region.
Cloud NAT is regional; one gateway is needed per region. Therefore, two Cloud NAT gateways are required. Option A is correct. Option B is wrong because a single gateway covers only one region. Option C is wrong because each subnet typically uses the regional gateway. Option D is wrong because Cloud NAT is not global.
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.
✗
None; Cloud NAT is not required for internet access.
Why it's wrong here
Cloud NAT provides outbound internet for VMs without external IPs.
✗
One Cloud NAT gateway per subnet.
Why it's wrong here
One gateway per region is sufficient; subnets share the regional gateway.
✓
Two Cloud NAT gateways, one per region.
Why this is correct
Cloud NAT is regional, so one per region is needed.
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 PCNE subnetting questions on CIDR, address ranges, and subnet selection.
Implementing a Virtual Private Cloud — This question tests Implementing a Virtual Private Cloud — CIDR notation defines the prefix length..
What is the correct answer to this question?
The correct answer is: Two Cloud NAT gateways, one per region. — Cloud NAT is regional; one gateway is needed per region. Therefore, two Cloud NAT gateways are required. Option A is correct. Option B is wrong because a single gateway covers only one region. Option C is wrong because each subnet typically uses the regional gateway. Option D is wrong because Cloud NAT is not global.
What should I do if I get this PCNE 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 PCNE 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 →
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 PCNE practice question is part of Courseiva's free Google Cloud 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 PCNE 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.