PCA Practice Exam 3 — 20 Questions

Question 1

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 2

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 3

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 4

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 5

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

Question 6

Which TWO of the following are true regarding Prometheus Histograms?

Accepted Answer

They are cumulative. Histograms consist of cumulative counters and allow for server-side quantile calculation.

Answer

They calculate quantiles client-side

Answer

They do not use labels

Answer

They are only for Gauges

Question 7

Why are traces considered distinct from metrics in observability?

Accepted Answer

Traces track individual request lifecycles through services.. Traces provide context on a single request's path through a distributed system, whereas metrics provide aggregated health status.

Answer

Traces are always numeric.

Answer

Traces are only for frontend applications.

Answer

Metrics replace traces.

Question 8

What is the primary goal of observability?

Accepted Answer

To understand system state from external outputs.. Observability aims to answer 'why' a system is in its current state by understanding its internal state through outputs (metrics, logs, traces).

Answer

To store as many logs as possible.

Answer

To automate code deployments.

Answer

To replace testing.

Question 9

Which THREE actions are commonly performed during the 'relabeling' phase in Prometheus?

Accepted Answer

Mapping multiple labels into one.. Replacing labels, dropping series, and mapping labels are standard relabeling actions.

Answer

Configuring the storage retention policy.

Answer

Increasing the memory of the Prometheus instance.

Question 10

Which Grafana panel type is best for showing a trend of a metric over time?

Accepted Answer

Time series. The Time series panel is the standard for plotting metrics over time.

Answer

Table

Answer

Stat

Answer

Bar gauge

Question 11

When configuring a dashboard panel, what is the significance of the 'Legend' field?

Accepted Answer

To rename the metric for display purposes. The legend field allows you to customize the labels displayed in the graph tooltip and legend section.

Answer

To set the alert threshold

Answer

To enable auto-refresh

Answer

To filter which metrics are shown

Question 12

A team wants to visualize metrics from Prometheus in Grafana. What is the standard way to connect these two services?

Accepted Answer

Add a 'Prometheus' data source in Grafana. Grafana allows users to add Prometheus as a 'Data Source' by providing the URL of the Prometheus server.

Answer

Upload a JSON file to Prometheus

Answer

Configure a Prometheus scrape job for Grafana

Answer

Install the 'Grafana-exporter' in Prometheus

Question 13

Your Prometheus server is hitting high memory usage due to high cardinality. Which action is most effective at reducing memory pressure?

Accepted Answer

Drop high-cardinality labels using relabel_configs. Reducing label cardinality (e.g., removing unique user IDs) is the primary way to reduce TSDB index size and memory usage.

Answer

Increase scrape_interval

Answer

Use more exporters

Answer

Enable remote write

Question 14

You are seeing 'Too many active series' in your Prometheus logs. Which action should be your first priority to address this?

Accepted Answer

Analyze the number of active series per label name.. Identifying which labels are causing the high cardinality is the standard first step to prevent OOM (Out Of Memory) crashes.

Answer

Switch to a different monitoring tool.

Answer

Disable all alerting rules.

Answer

Increase Prometheus memory limits.

Question 15

What is the primary role of the 'Alertmanager'?

Accepted Answer

To manage and route alerts generated by Prometheus.. Alertmanager is responsible for grouping, silencing, and routing alerts to external systems like PagerDuty or email.

Answer

To store long-term metric data.

Answer

To scrape metrics from targets.

Answer

To visualize metrics in dashboards.

Question 16

When evaluating the 'Traffic' golden signal, what is the best metric to watch for a web service?

Accepted Answer

Requests per second.. Request rate (requests per second) is the standard way to measure traffic volume.

Answer

CPU usage percentage.

Answer

HTTP error count.

Answer

Response latency.

Question 17

What does the 'firing' state mean for an alert?

Accepted Answer

The alert condition is currently true. An alert enters the 'firing' state when its condition expression evaluates to true for the specified 'for' duration.

Answer

The alert is being silenced

Answer

The alert is pending

Answer

The alert has been resolved

Question 18

Which THREE features are provided by Grafana when used with Prometheus?

Accepted Answer

Customizable dashboard visualization.. Visualization, dashboard templating, and alert integration are core Grafana features.

Answer

Long-term storage of metrics.

Answer

Automatic code deployment.

Question 19

What is the purpose of a 'grouping' configuration in the Alertmanager 'route' block?

Accepted Answer

To aggregate similar alerts into a single notification. Grouping categorizes multiple alerts into a single notification based on common label sets, reducing alert fatigue.

Answer

To inhibit alerts based on severity

Answer

To ensure alerts are processed in alphabetical order

Answer

To create hierarchical alert routing

Question 20

Which THREE factors contribute to a 'high cardinality' problem in a Prometheus environment?

Accepted Answer

Adding high-variance values like email addresses to labels.. High cardinality is caused by labels with many unique values, like timestamps, user IDs, or un-normalized request paths.

Answer

Using a low scrape interval.

Answer

Using too many scrape targets.