- A
The SSL certificate is expired.
Why wrong: An expired SSL certificate would cause client-side errors, not 502s from the backend.
- B
The Cloud Run service requires IAP authentication.
Why wrong: IAP is not related to 502 errors; it would cause 401/403.
- C
The health check is misconfigured for serverless NEGs.
Why wrong: Serverless NEGs do not require health checks; the load balancer uses a default health check.
- D
The serverless NEG is in a different region than the load balancer's forwarding rule.
For a global load balancer, the serverless NEG must be in a supported region and the load balancer must be configured to route to that region.
Question 815 of 982
PCNE Configuring Network Services Practice Question
This PCNE practice question tests your understanding of configuring network services. 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 global HTTPS load balancer is configured with a backend service that points to a serverless NEG for Cloud Run services. Some requests are failing with 502 errors. What is a likely cause?
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
✓
The serverless NEG is in a different region than the load balancer's forwarding rule.
Serverless NEGs require the load balancer to be in the same region as the Cloud Run service, or use a global external load balancer with serverless NEGs in multiple regions. A 502 error often indicates connectivity issues, such as the load balancer not being able to reach the backend due to missing network endpoint group or incorrect region.
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.
- ✗
The SSL certificate is expired.
Why it's wrong here
An expired SSL certificate would cause client-side errors, not 502s from the backend.
- ✗
The Cloud Run service requires IAP authentication.
Why it's wrong here
IAP is not related to 502 errors; it would cause 401/403.
- ✗
The health check is misconfigured for serverless NEGs.
Why it's wrong here
Serverless NEGs do not require health checks; the load balancer uses a default health check.
- ✓
The serverless NEG is in a different region than the load balancer's forwarding rule.
Why this is correct
For a global load balancer, the serverless NEG must be in a supported region and the load balancer must be configured to route to that region.
Related concept
Read the scenario before looking for a memorised answer.
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 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.
Quick reference
Cloud Service Model Comparison
| Model | You Manage | Provider Manages | Examples |
|---|---|---|---|
| IaaS | OS, runtime, apps, data | Hardware, hypervisor, networking | EC2, Azure VMs, GCP Compute Engine |
| PaaS | Apps and data | OS, runtime, middleware, hardware | Elastic Beanstalk, Azure App Service |
| SaaS | Data and settings only | Everything else | Microsoft 365, Salesforce, Workday |
| FaaS / Serverless | Function code only | Infra, scaling, runtime | Lambda, Azure Functions, Cloud Run |
| CaaS | Containers and apps | Kubernetes, OS, hardware | EKS, AKS, GKE |
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.
- →
Configuring Network Services — study guide chapter
Learn the concepts, then practise the questions
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FAQ
Questions learners often ask
What does this PCNE question test?
Configuring Network Services — This question tests Configuring Network Services — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: The serverless NEG is in a different region than the load balancer's forwarding rule. — Serverless NEGs require the load balancer to be in the same region as the Cloud Run service, or use a global external load balancer with serverless NEGs in multiple regions. A 502 error often indicates connectivity issues, such as the load balancer not being able to reach the backend due to missing network endpoint group or incorrect region.
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 →
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.
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