PCA Monitoring, Alerting & Troubleshooting 2

Question 1

An Alertmanager route has `group_wait: 30s` and `group_interval: 5m`. A second alert fires in the same group 10 seconds after the first. When will the second alert be sent?

Accepted Answer

Together with the first alert after the 30s group_wait expires

Answer

Alerts in the same group are batched together; the second alert joins the existing group and is sent when the group_wait of 30s expires.

Question 2

Which Prometheus metric type is most appropriate for tracking the total number of HTTP requests served since process start?

Accepted Answer

Counter

Answer

Counters are monotonically increasing values ideal for cumulative totals like request counts.

Question 3

A Prometheus alert has been in the `PENDING` state for longer than the configured `for` duration but has not transitioned to `FIRING`. What is the most likely cause?

Accepted Answer

The alert condition became false before the for-duration elapsed

Answer

If the alert condition resolves before the for-duration completes, the alert resets to inactive without ever firing.

Question 4

What does the `absent()` function return when the time series passed to it exists and has a value?

Accepted Answer

An empty vector

Answer

absent() returns an empty vector when the time series is present, and a vector with value 1 only when the series is absent.

Question 5

In Prometheus, what is the effect of setting `honor_labels: true` on a scrape configuration?

Accepted Answer

Conflicting labels from the target override Prometheus-assigned labels

Answer

With honor_labels: true, if the target exposes a label that conflicts with a Prometheus-set label, the target's label wins.

(PCA) Prometheus Certified Associate Practice Test

(PCA) Prometheus Certified Associate Practice Test

PCA Monitoring, Alerting & Troubleshooting 2