PCA Practice Test 2 — 25 Questions

Question 1

Which THREE of the following are true about the Prometheus Text Exposition Format?

Accepted Answer

It is line-oriented. It is line-oriented, supports comments starting with #, and each metric line contains the name, optional labels, and value.

Answer

It is a binary protocol

Answer

It requires an XML schema

Question 2

Which Grafana feature allows you to see data from multiple Prometheus servers on a single panel?

Accepted Answer

Data source variables. Grafana allows you to define multiple data sources and even mix them within a dashboard, or use a data source proxy.

Answer

Panel injection

Answer

Metric merging

Answer

Prometheus federation

Question 3

What is the effect of using a 'Summary' metric with client-side quantiles?

Accepted Answer

It prevents cross-instance aggregation. Client-side quantiles are calculated per instance, making it impossible to aggregate them across multiple instances of an application.

Answer

It improves performance

Answer

It allows cross-instance aggregation

Answer

It doubles the scrape time

Question 4

Which THREE of the following are standard ways to send notifications from Alertmanager?

Accepted Answer

Webhook. Webhook, Email, and PagerDuty are built-in, widely used receiver types.

Answer

FTP

Answer

SSH

Question 5

What is the default port that Prometheus listens on?

Accepted Answer

9090. 9090 is the well-known default port for the Prometheus server web interface.

Answer

9100

Answer

9093

Answer

8080

Question 6

What is the purpose of the 'rule_files' configuration?

Accepted Answer

To define alerting and recording rules. rule_files point to recording and alerting rules that Prometheus evaluates.

Answer

To manage user authentication

Answer

To define static targets

Answer

To configure global retention

Question 7

What happens if a label set for a metric changes during its lifetime?

Accepted Answer

A new time series is created. Changing a label set creates a brand new time series in Prometheus.

Answer

An error is logged

Answer

The series is updated in-place

Answer

The metric is deleted

Question 8

When writing a custom exporter in Python, what is the most common way to expose the metrics?

Accepted Answer

Using start_http_server(). The prometheus_client library provides a start_http_server() method to expose metrics on a specified port.

Answer

Writing to a file

Answer

Using a message queue

Answer

Using a database connection

Question 9

What does the `_count` suffix denote in a summary or histogram?

Accepted Answer

The total number of samples. The _count suffix represents the total number of observations made for that specific metric.

Answer

The maximum value

Answer

The sum of values

Answer

The current bucket value

Question 10

You are implementing a custom exporter for a legacy database. The database provides a single value representing the number of active connections. Which metric type should you use to best represent this data?

Accepted Answer

Gauge. Because active connections fluctuate up and down as users connect and disconnect, a Gauge is the appropriate metric type for representing a snapshot of the current state.

Answer

Summary

Answer

Histogram

Answer

Counter

Question 11

Which of the following describes the 'pull' model's benefit regarding service discovery?

Accepted Answer

Targets don't need to know where Prometheus is.. Prometheus can dynamically discover targets (via Kubernetes API, Consul, etc.) and automatically start scraping, removing the need to register every new pod.

Answer

Prometheus is always the first to start.

Answer

Targets push data when they are ready.

Answer

It reduces network traffic.

Question 12

Which of these is NOT a Golden Signal?

Accepted Answer

Storage. The Four Golden Signals are Latency, Traffic, Errors, and Saturation. 'Storage' is not one of them.

Answer

Latency

Answer

Saturation

Answer

Errors

Question 13

You need to prevent an alert from firing if a maintenance window is active. How should you approach this in Alertmanager?

Accepted Answer

Use a Silence. Silences are the standard way to prevent specific alerts from firing during a known maintenance period.

Answer

Delete the alerting rule

Answer

Modify the routing tree

Answer

Add a 'skip' label to the rule

Question 14

Which annotation is commonly used to provide a human-readable description in an alert?

Accepted Answer

description. The 'summary' or 'description' annotations are standard practices for providing context in alert notifications.

Answer

severity

Answer

instance

Answer

job

Question 15

Which THREE of the following are valid Alertmanager routing tree parameters?

Accepted Answer

receiver. Routes can filter by 'match', 'match_re', and define a 'receiver'.

Answer

server

Answer

auth_token

Question 16

When running node_exporter, how can you disable specific collectors like 'textfile'?

Accepted Answer

--no-collector.textfile. Collectors can be disabled using the --no-collector.<name> flag.

Answer

collector.textfile=false

Answer

exclude=textfile

Answer

--disable-textfile

Question 17

Which TWO of the following are benefits of using recording rules?

Accepted Answer

Simplifying complex queries. Recording rules improve performance for dashboards and provide pre-computed metrics for alerting.

Answer

Adding authentication to metrics

Answer

Automatically increasing retention

Answer

Providing UI for alerts

Question 18

Which of the following best describes the function of the 'continue: true' setting within an Alertmanager route?

Accepted Answer

It allows an alert to continue matching against sibling routes. Setting 'continue: true' allows an alert to match multiple routes, ensuring it can be sent to multiple destinations if desired.

Answer

It enables alert silencing

Answer

It allows the Alertmanager to retry failed notifications

Answer

It causes the alert to stay active indefinitely

Question 19

Which metric type is best for reporting the number of requests received by a service?

Accepted Answer

Counter. Counters are monotonic; they only go up, which is perfect for request counts.

Answer

Summary

Answer

Histogram

Answer

Gauge

Question 20

You need to track the number of requests received by your application. Which metric type should you choose?

Accepted Answer

Counter. A counter is a cumulative metric that represents a single monotonically increasing counter whose value can only increase or be reset to zero on restart.

Answer

Summary

Answer

Gauge

Answer

Histogram