- A
Configure Private Google Access on the subnet.
Why wrong: Private Google Access only allows access to Google APIs, not general internet.
- B
Create a VPC firewall rule to allow egress to 0.0.0.0/0.
Why wrong: A firewall rule alone does not provide internet access without an external IP or NAT.
- C
Create a Cloud NAT gateway and a Cloud Router in us-central1.
Cloud NAT requires a Cloud Router in the same region to provide outbound connectivity.
- D
Assign a static external IP to the instance.
Why wrong: The requirement is to not have external IPs on the instance.
Question 345 of 982
PCNE Implementing VPC Instances Practice Question
This PCNE practice question tests your understanding of implementing vpc instances. 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 a subnet in us-central1. They launched a Compute Engine instance named "app-server" in that subnet without an external IP. They need the instance to be able to download updates from the internet. Which two steps must be taken?
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
✓
Create a Cloud NAT gateway and a Cloud Router in us-central1.
The instance needs outbound internet access via Cloud NAT, which requires a Cloud Router in the region.
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.
- ✗
Configure Private Google Access on the subnet.
Why it's wrong here
Private Google Access only allows access to Google APIs, not general internet.
- ✗
Create a VPC firewall rule to allow egress to 0.0.0.0/0.
- ✓
Create a Cloud NAT gateway and a Cloud Router in us-central1.
- ✗
Assign a static external IP to the instance.
Why it's wrong here
The requirement is to not have external IPs on the instance.
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.
Visual reference
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 VPC Instances — study guide chapter
Learn the concepts, then practise the questions
- →
Implementing VPC Instances practice questions
Targeted practice on this topic area only
- →
All PCNE questions
982 questions across all exam domains
- →
Google Professional Cloud Network Engineer study guide
Full concept coverage aligned to exam objectives
- →
PCNE practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related PCNE practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Configuring Network Services practice questions
Practise PCNE questions linked to Configuring Network Services.
Implementing Hybrid Interconnectivity practice questions
Practise PCNE questions linked to Implementing Hybrid Interconnectivity.
Managing, Monitoring, and Optimising Network Operations practice questions
Practise PCNE questions linked to Managing, Monitoring, and Optimising Network Operations.
Designing, Planning, and Prototyping a GCP Network practice questions
Practise PCNE questions linked to Designing, Planning, and Prototyping a GCP Network.
Implementing VPC Instances practice questions
Practise PCNE questions linked to Implementing VPC Instances.
Implementing network security practice questions
Practise PCNE questions linked to Implementing network security.
Implementing a Virtual Private Cloud practice questions
Practise PCNE questions linked to Implementing a Virtual Private Cloud.
PCNE fundamentals practice questions
Practise PCNE questions linked to PCNE fundamentals.
PCNE scenario practice questions
Practise PCNE questions linked to PCNE scenario.
PCNE troubleshooting practice questions
Practise PCNE questions linked to PCNE troubleshooting.
Practice this exam
Start a free PCNE 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 PCNE question test?
Implementing VPC Instances — This question tests Implementing VPC Instances — CIDR notation defines the prefix length..
What is the correct answer to this question?
The correct answer is: Create a Cloud NAT gateway and a Cloud Router in us-central1. — The instance needs outbound internet access via Cloud NAT, which requires a Cloud Router in the region.
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 →
Last reviewed: Jul 4, 2026
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.