← PCDOE·Google Cloud

Question 5 of 500

Implementing service monitoring strategies →mediumMultiple ChoiceObjective-mapped

Quick Answer

The answer is that the relabel_config for port incorrectly constructs the target address by hardcoding ':8080' instead of using the annotation value dynamically. This is the most likely cause of the Prometheus relabel_config port construction error because when Prometheus scrapes pods with the label 'app: my-app' and the annotation 'prometheus.io/scrape: true', the relabeling rule should pull the port from `__meta_kubernetes_annotation_prometheus_io_port` and use it directly. Appending a static port overrides whatever the annotation specifies, so if the annotation defines a different port or is absent, the scrape target becomes invalid and no metrics are collected. On the Google Professional Cloud DevOps Engineer exam, this scenario tests your understanding of how Kubernetes service discovery metadata flows into Prometheus relabeling—a common trap is assuming you can hardcode ports when the annotation is present. Remember the mnemonic: "Annotate, don't hardcode—let the metadata load."

PCDOE Implementing service monitoring strategies Practice Question

This PCDOE practice question tests your understanding of implementing service monitoring strategies. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. 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.

Exhibit

Refer to the exhibit.

```
# prometheus.yml
scrape_configs:
  - job_name: 'my-app'
    kubernetes_sd_configs:
    - role: pod
    relabel_configs:
    - source_labels: [__meta_kubernetes_pod_label_app]
      regex: my-app
      action: keep
    - source_labels: [__meta_kubernetes_pod_annotation_prometheus_io_scrape]
      regex: "true"
      action: keep
    - source_labels: [__meta_kubernetes_pod_annotation_prometheus_io_port]
      action: replace
      target_label: __address__
      regex: (.+)
      replacement: $1:8080
```

A team has deployed a Prometheus server on GKE using the configuration above. They expect Prometheus to scrape metrics from pods with the label 'app: my-app' and the annotation 'prometheus.io/scrape: true' on port 8080. However, no metrics are being collected. What is the most likely cause?

Clue words in this question

Noticing these words before you look at the options changes how you read each choice.

Clue: "most likely"
Why it matters: Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.

Question 1mediummultiple choice

Full question →

Exhibit

Refer to the exhibit.

```
# prometheus.yml
scrape_configs:
  - job_name: 'my-app'
    kubernetes_sd_configs:
    - role: pod
    relabel_configs:
    - source_labels: [__meta_kubernetes_pod_label_app]
      regex: my-app
      action: keep
    - source_labels: [__meta_kubernetes_pod_annotation_prometheus_io_scrape]
      regex: "true"
      action: keep
    - source_labels: [__meta_kubernetes_pod_annotation_prometheus_io_port]
      action: replace
      target_label: __address__
      regex: (.+)
      replacement: $1:8080
```

A
The kubernetes_sd_configs role is set to 'pod' but should be 'endpoints'.
Why wrong: Role 'pod' is correct for scraping pods directly.
B
Prometheus needs to be configured to listen on port 9090 for scraping.
Why wrong: Prometheus listens on 9090 for its UI, not for scraping; scraping uses the target port.
C
The keep action for the label 'my-app' is filtering out all pods.
Why wrong: If the label is correct, pods are kept.
D
The relabel_config for port incorrectly constructs the target address; it should use the annotation value directly without appending ':8080'.
The port annotation usually includes the port number, so appending a fixed port is wrong.

Full breakdown with real-world context →

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 relabel_config for port incorrectly constructs the target address; it should use the annotation value directly without appending ':8080'.

Option D is correct because the relabel_config is incorrectly constructing the target address. The configuration likely uses `__meta_kubernetes_annotation_prometheus_io_port` to get the port, but then appends ':8080' statically, overriding the annotation value. If the annotation specifies a different port or is missing, this hardcoded port causes Prometheus to scrape the wrong endpoint or fail entirely. The correct approach is to use the annotation value directly without appending a fixed port, or to use a default port only when the annotation is absent.

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 kubernetes_sd_configs role is set to 'pod' but should be 'endpoints'.
Why it's wrong here
Role 'pod' is correct for scraping pods directly.
✗
Prometheus needs to be configured to listen on port 9090 for scraping.
Why it's wrong here
Prometheus listens on 9090 for its UI, not for scraping; scraping uses the target port.
✗
The keep action for the label 'my-app' is filtering out all pods.
Why it's wrong here
If the label is correct, pods are kept.
✓
The relabel_config for port incorrectly constructs the target address; it should use the annotation value directly without appending ':8080'.
Why this is correct
The port annotation usually includes the port number, so appending a fixed port is wrong.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.

Common exam traps

Common exam trap: answer the scenario, not the keyword

The trap here is that candidates often overlook the relabel_config port construction and assume the issue is with service discovery roles or label filtering, when in fact the static port override is the subtle cause of scrape failures.

Detailed technical explanation

How to think about this question

Prometheus relabeling uses `__meta_kubernetes_*` labels from Kubernetes service discovery to dynamically construct scrape targets. The `__meta_kubernetes_pod_annotation_prometheus_io_port` label holds the port from the annotation, and the `__meta_kubernetes_pod_annotation_prometheus_io_scrape` label indicates whether to scrape. If the relabel config hardcodes a port like ':8080' instead of using `$1` from a regex capture group on the annotation value, it ignores the actual annotation port, causing mismatches. This is a common misconfiguration when operators assume a fixed port without validating annotation values.

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 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.

Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.

Related PCDOE practice-question pages

Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.

Bootstrapping a Google Cloud organization for DevOps practice questions

Practise PCDOE questions linked to Bootstrapping a Google Cloud organization for DevOps.

Managing service incidents practice questions

Practise PCDOE questions linked to Managing service incidents.

Managing Google Cloud costs practice questions

Practise PCDOE questions linked to Managing Google Cloud costs.

Building and implementing CI/CD pipelines practice questions

Practise PCDOE questions linked to Building and implementing CI/CD pipelines.

Implementing service monitoring strategies practice questions

Practise PCDOE questions linked to Implementing service monitoring strategies.

Optimizing service performance practice questions

Practise PCDOE questions linked to Optimizing service performance.

PCDOE fundamentals practice questions

Practise PCDOE questions linked to PCDOE fundamentals.

PCDOE scenario practice questions

Practise PCDOE questions linked to PCDOE scenario.

PCDOE troubleshooting practice questions

Practise PCDOE questions linked to PCDOE troubleshooting.

Practice this exam

Start a free PCDOE practice session

Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.

10 questions 20 questions 30 questions 50 questions Timed 30

PCDOE practice-test guide →Study guide →Browse all practice tests

FAQ

Questions learners often ask

What does this PCDOE question test?

Implementing service monitoring strategies — This question tests Implementing service monitoring strategies — Read the scenario before looking for a memorised answer..

What is the correct answer to this question?

The correct answer is: The relabel_config for port incorrectly constructs the target address; it should use the annotation value directly without appending ':8080'. — Option D is correct because the relabel_config is incorrectly constructing the target address. The configuration likely uses `__meta_kubernetes_annotation_prometheus_io_port` to get the port, but then appends ':8080' statically, overriding the annotation value. If the annotation specifies a different port or is missing, this hardcoded port causes Prometheus to scrape the wrong endpoint or fail entirely. The correct approach is to use the annotation value directly without appending a fixed port, or to use a default port only when the annotation is absent.

What should I do if I get this PCDOE question wrong?

Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.

Are there clue words in this question I should notice?

Yes — watch for: "most likely". Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.

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 →

How Courseiva writes practice questions · Editorial policy

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.

Loading comments…

This PCDOE 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 PCDOE exam.