PCA Practice Test 9 — 10 Questions

Question 1

Which metric type is most appropriate for tracking the current total number of active user sessions?

Accepted Answer

Gauge. Since the count of active sessions can rise and fall, a gauge is the correct metric type.

Answer

Summary

Answer

Counter

Answer

Histogram

Question 2

Which TWO factors directly influence the accuracy of quantile calculations when using Prometheus Summary metrics?

Accepted Answer

The configured quantiles (e.g., 0.9, 0.99).. Summaries compute quantiles on the client side, and accuracy is determined by the configured quantiles and the sliding time window over which they are calculated.

Answer

The total number of instances scraping the metric.

Answer

The CPU architecture of the client host.

Answer

The number of buckets defined in the configuration.

Question 3

An SRE team is transitioning from traditional logs to metrics for performance monitoring. Which scenario best justifies using metrics over logs?

Accepted Answer

Tracking the request rate per second on a web server.. Metrics are numerical representations of data measured over time, making them efficient for time-series analysis and alerting, whereas logs are better for debugging specific events.

Answer

Auditing user access attempts for compliance.

Answer

Storing the payload of a failed transaction for later inspection.

Answer

Recording the stack trace of a Java application crash.

Question 4

Which component is responsible for executing queries written in PromQL?

Accepted Answer

Prometheus Server. The Prometheus server itself contains the query engine that processes PromQL expressions.

Answer

Exporter

Answer

Alertmanager

Answer

Grafana

Question 5

Why are 'logs' essential for debugging, even with perfect metrics?

Accepted Answer

Logs contain detailed context about specific events.. Logs provide the granular, detailed context (like specific error messages or stack traces) that metrics cannot provide.

Answer

Metrics are too slow.

Answer

Logs are free to store.

Answer

Metrics cannot be used for debugging.

Question 6

How do you apply a global notification delay in Alertmanager?

Accepted Answer

By using the group_wait field. The 'group_wait' parameter at the root route level defines the time to wait before sending an initial notification for a new alert group.

Answer

By setting the repeat_interval

Answer

By creating a silence for the first 5 minutes

Answer

By modifying the Prometheus rule interval

Question 7

You have a recording rule that fails to evaluate because of a 'labels conflict'. What is the most likely cause?

Accepted Answer

The aggregation results in duplicate label sets. A label conflict occurs when the recording rule tries to create a metric with labels that are already present or restricted, or when the aggregation produces duplicate label sets.

Answer

The rule file has invalid YAML indentation

Answer

The evaluation interval is too low

Answer

The metric name is already in use

Question 8

You are creating a recording rule to calculate the rate of requests over 5 minutes. Why would you prefer a recording rule over a direct dashboard query?

Accepted Answer

To reduce query latency on dashboards. Recording rules precompute expensive queries, reducing the load on Prometheus and speeding up dashboard loading times.

Answer

To bypass the retention settings of Prometheus

Answer

To increase the resolution of the data

Answer

To automatically send alerts to PagerDuty

Question 9

What is the default port used by node_exporter?

Accepted Answer

9100. The standard Prometheus convention for node_exporter is port 9100.

Answer

9115

Answer

9090

Answer

8080

Question 10

Which TWO of the following are common reasons to use the Pushgateway?

Accepted Answer

For batch jobs that run for seconds. Pushgateway is used for batch jobs that finish quickly and for processes that are behind a firewall.

Answer

To monitor long-running servers

Answer

To act as a reverse proxy

Answer

When metrics need to be stored in SQL