- A
Configure a firewall rule to allow health check probes from the load balancer's health check ranges.
Health check probes must be permitted by firewall rules to validate backend health.
- B
Enable HTTP health check on the backend service.
Why wrong: Health checks are already configured; enabling another one is unnecessary.
- C
Assign an external IP address to each backend instance.
Why wrong: External IPs are not required for load-balanced backends and may introduce security concerns.
- D
Add a route for the load balancer's IP range.
Why wrong: Routes are not required for load balancer traffic; the load balancer handles forwarding internally.
Question 37 of 1,000
easyMultiple ChoiceObjective-mapped
PCNE Practice Question: A company has deployed an HTTP load balancer with…
This PCNE practice question tests your understanding of pcne exam topics. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. 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 deployed an HTTP load balancer with a backend service configured to use an unmanaged instance group. Users report that traffic is not reaching the backend instances. The backend instances are healthy and have proper firewall rules allowing traffic from the load balancer. What step should the network engineer take to resolve the issue?
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
✓
Configure a firewall rule to allow health check probes from the load balancer's health check ranges.
The issue is that health check probes are being blocked by firewall rules. For the load balancer to consider backend instances healthy, it must be able to send health check probes to them. These probes originate from specific IP ranges (e.g., 130.211.0.0/22 and 35.191.0.0/16 for Google Cloud). A firewall rule must allow ingress traffic from these health check ranges to the instances. Option A corrects this. Option B is not needed because an HTTP health check is already configured as part of the backend service (the load balancer performs health checks by default). Option C is not required because backend instances can have only internal IPs; the load balancer forwards traffic to them using their internal IPs. Option D is unnecessary because the load balancer's VIP is not used as a destination for traffic from the load balancer to instances.
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.
- ✓
Configure a firewall rule to allow health check probes from the load balancer's health check ranges.
Why this is correct
Health check probes must be permitted by firewall rules to validate backend health.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Enable HTTP health check on the backend service.
Why it's wrong here
Health checks are already configured; enabling another one is unnecessary.
- ✗
Assign an external IP address to each backend instance.
Why it's wrong here
External IPs are not required for load-balanced backends and may introduce security concerns.
- ✗
Add a route for the load balancer's IP range.
Why it's wrong here
Routes are not required for load balancer traffic; the load balancer handles forwarding internally.
Common exam traps
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.
Visual reference
What to study next
Got this wrong? Here's your next step.
Identify which PCNE 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.
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?
Read the scenario before looking for a memorised answer.
What is the correct answer to this question?
The correct answer is: Configure a firewall rule to allow health check probes from the load balancer's health check ranges. — The issue is that health check probes are being blocked by firewall rules. For the load balancer to consider backend instances healthy, it must be able to send health check probes to them. These probes originate from specific IP ranges (e.g., 130.211.0.0/22 and 35.191.0.0/16 for Google Cloud). A firewall rule must allow ingress traffic from these health check ranges to the instances. Option A corrects this. Option B is not needed because an HTTP health check is already configured as part of the backend service (the load balancer performs health checks by default). Option C is not required because backend instances can have only internal IPs; the load balancer forwards traffic to them using their internal IPs. Option D is unnecessary because the load balancer's VIP is not used as a destination for traffic from the load balancer to instances.
What should I do if I get this PCNE question wrong?
Identify which PCNE 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.
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 →
Keep practising
More PCNE practice questions
- An organization is migrating to Google Cloud and requires connectivity between their on-premises network and VPC. They p…
- A company is migrating on-premises DNS to Google Cloud. They have a hybrid network using Cloud VPN and want to resolve o…
- A network engineer is configuring a Cloud Router for BGP peering with an on-premises router over a VPN tunnel. The on-pr…
- A company uses Cloud NAT to allow private instances to reach the internet. They notice that egress traffic from Compute…
- You are setting up Partner Interconnect with a service provider that offers both Layer 2 and Layer 3 options. Your on-pr…
- Match each VPC networking concept to its definition.
Last reviewed: Jun 24, 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.