Linux Foundation / CNCF PCA: Prometheus Certified Associate

Last checked October 22, 2026 against the official Linux Foundation / CNCF exam page.

1. Question 1Observability and Prometheus fundamentals

   Prometheus collects metrics using a pull model. What does this mean?

   1. ATargets push every metric to Prometheus as soon as it changes over a connection each target opens
   2. BMetrics are sent through weekly e-mail summaries emailed to an operator
   3. CThe Prometheus server scrapes HTTP endpoints exposed by targets at a set interval
   4. DPrometheus reads metric values from the target's local disk directly
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   Correct answer: C

   In the pull model, the Prometheus server periodically scrapes metrics endpoints on targets. Push-based systems send data from the target, email is not a metrics transport, and Prometheus does not read target disks.

2. Question 2PromQL and querying

   A team wants the per-second rate of HTTP requests from a counter over the last five minutes. Which PromQL expression is appropriate?

   1. Ahttp_requests_total + 5m
   2. Bsum(http_requests_total) by minute
   3. Cavg_over_time(http_requests_total)
   4. Drate(http_requests_total[5m])
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   Correct answer: D

   rate() computes the per-second average increase of a counter over a range, which suits request rates. Adding a duration, invalid sum syntax and avg_over_time without a range are incorrect.

3. Question 3Alerting and visualization

   An alert should fire only if the error rate stays above a threshold for five minutes. Which alert rule element implements this?

   1. AThe labels section with a severity and team value
   2. BThe for clause with a duration of five minutes
   3. CThe receiver name set in the Alertmanager route tree
   4. DThe annotations section holding a summary and runbook URL
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   Correct answer: B

   The for clause requires the condition to hold for a specified duration before the alert fires. Annotations provide descriptions, labels classify alerts, and receivers are notification endpoints.

4. Question 4Instrumentation and exporters

   A developer adds a counter to an application to track failed payments. Which label design is recommended?

   1. AUse a random UUID generated for each incoming request as a label value in the metric
   2. BUse a small, bounded set of label values such as payment provider and region
   3. CUse each customer's email address as a label on every failed payment
   4. DUse the full raw request body as a label on the failed payment counter
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   Correct answer: B

   Bounded labels keep cardinality manageable. Emails, random UUIDs and request bodies create high-cardinality series that strain Prometheus.

5. Question 5Observability and Prometheus fundamentals

   In Prometheus, what is a time series identified by?

   1. AA hostname with no label set
   2. BA metric name and a set of labels
   3. CA file name and a time stamp
   4. DA user's email address and birthdate
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   Correct answer: B

   A Prometheus time series is identified by its metric name and its label set. File names, email addresses and hostnames without labels do not define a series.