PCA Alerting And Dashboarding Practice Test 2 — 15 Questions

Question 1

You are seeing 'Alerting rule evaluation error' in your logs. What is the most likely cause?

Accepted Answer

Invalid PromQL in the expression. Syntactic errors in the PromQL query within an alerting rule will cause evaluation failures.

Answer

Alertmanager is down

Answer

Too many dashboards

Answer

Prometheus is out of disk space

Question 2

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 3

What is the purpose of the 'labels' field in an alerting rule?

Accepted Answer

To add metadata for routing and filtering. Labels allow you to attach metadata to the alert, which can then be used in Alertmanager for routing and grouping.

Answer

To define the alert message body

Answer

To select the target server

Answer

To set the alert severity level

Question 4

When using the 'repeat_interval' in Alertmanager, what does it define?

Accepted Answer

How often to resend firing alerts. The repeat_interval defines how long to wait before re-sending a notification for an alert that is still active.

Answer

The timeout for the receiver

Answer

The TTL of the alert

Answer

How long to wait before firing

Question 5

You want to notify different teams based on the 'service' label of an alert. Where should you configure this logic?

Accepted Answer

In the Alertmanager configuration. The Alertmanager configuration file contains the routing tree that maps alerts to receivers based on labels.

Answer

In the node exporter config

Answer

In the Grafana data source

Answer

In the Prometheus alerting rule

Question 6

What happens to your alerts if the Alertmanager configuration file contains a syntax error?

Accepted Answer

Alertmanager continues using the previous configuration. If the configuration is invalid, Alertmanager will fail to reload, and it will continue using the last known good configuration.

Answer

Prometheus stops scraping

Answer

Alertmanager crashes immediately

Answer

All alerts are dropped

Question 7

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 8

In Alertmanager, what is the role of the 'continue' field in a route?

Accepted Answer

To force the alert to be sent to multiple routes. If 'continue' is set to true, Alertmanager will match the alert against subsequent sibling routes instead of stopping at the first match.

Answer

To keep the alert firing after resolution

Answer

To ignore duplicate alerts

Answer

To restart the Alertmanager process

Question 9

Which tool allows you to visualize Prometheus alerts directly in a web UI?

Accepted Answer

Alertmanager UI. The Prometheus built-in web UI provides an 'Alerts' tab to view current alert statuses.

Answer

Node Exporter

Answer

Pushgateway

Answer

Prometheus CLI

Question 10

You have a recording rule that uses 'sum() by (instance)'. Why might this be inefficient for large clusters?

Accepted Answer

It can lead to high cardinality if 'instance' has many values. High cardinality labels, if not handled correctly, can lead to a massive number of time series, consuming excessive memory and storage.

Answer

It blocks concurrent queries

Answer

It uses too much disk I/O

Answer

It slows down the network

Question 11

You want to ensure that if the Alertmanager cluster loses communication, alerts are still sent. Which configuration helps achieve this?

Accepted Answer

Use the --cluster.peer flag. High Availability (HA) for Alertmanager is achieved by running multiple instances and using the '--cluster.peer' flag to link them.

Answer

Disable grouping

Answer

Set repeat_interval to 0

Answer

Use a load balancer only

Question 12

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 13

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 14

You have a recording rule that references a metric that doesn't exist. What is the impact?

Accepted Answer

The rule evaluation results in no data. The recording rule will be evaluated, but because the expression returns no data, no new time series will be created for that rule.

Answer

Prometheus logs a critical error

Answer

The entire server crashes

Answer

The rule is automatically disabled

Question 15

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