Observability interview questions

33 Observability questions from the MLOps & Integration bank, written for Indian campus drives and tech interviews. Every question has a verified answer and an AI-tutor explanation on placd.

Free to start: the 2-minute IT readiness check — six questions and a result.

Take the free IT readiness check

or take a mock interview set up for this area

1. What is Three pillars?

Junior
  1. A.a visualization tool that builds dashboards over Prometheus, Loki, Elasticsearch and other sources
  2. B.metrics, logs and traces — the complementary signals that together explain system behavior
  3. C.keeping only a fraction of traces (head- or tail-based) to control telemetry volume and cost
  4. D.the Elastic Stack UI for searching, visualizing and dashboarding indexed log data

Answer + AI explanation with Pro

2. Which term means: "metrics, logs and traces — the complementary signals that together explain system behavior"?

Junior
  1. A.Langfuse
  2. B.Cardinality
  3. C.Three pillars
  4. D.OTel Collector

Answer + AI explanation with Pro

3. Which statement is correct?

Junior
  1. A.Three pillars — keeping only a fraction of traces (head- or tail-based) to control telemetry volume and cost
  2. B.Three pillars — a pipeline that receives, processes and exports telemetry, decoupling apps from backends
  3. C.Three pillars — metrics, logs and traces — the complementary signals that together explain system behavior
  4. D.Three pillars — an LLM-focused observability platform that traces prompts, tokens, cost and latency and runs evals

Answer + AI explanation with Pro

4. What is OpenTelemetry?

Junior
  1. A.keeping only a fraction of traces (head- or tail-based) to control telemetry volume and cost
  2. B.a visualization tool that builds dashboards over Prometheus, Loki, Elasticsearch and other sources
  3. C.a vendor-neutral standard and SDK for generating and exporting traces, metrics and logs
  4. D.a pipeline that receives, processes and exports telemetry, decoupling apps from backends

Answer + AI explanation with Pro

5. Which term means: "a vendor-neutral standard and SDK for generating and exporting traces, metrics and logs"?

Junior
  1. A.Sampling
  2. B.OpenTelemetry
  3. C.Cardinality
  4. D.Elastic Stack (ELK)

Answer + AI explanation with Pro

6. Which statement is correct?

Junior
  1. A.OpenTelemetry — passing trace and span IDs across service calls so one request is stitched into a single trace
  2. B.OpenTelemetry — a visualization tool that builds dashboards over Prometheus, Loki, Elasticsearch and other sources
  3. C.OpenTelemetry — the Elastic Stack UI for searching, visualizing and dashboarding indexed log data
  4. D.OpenTelemetry — a vendor-neutral standard and SDK for generating and exporting traces, metrics and logs

Answer + AI explanation with Pro

7. What is Span?

Mid
  1. A.the number of unique label/value combinations in metrics; high cardinality can overwhelm a TSDB
  2. B.a visualization tool that builds dashboards over Prometheus, Loki, Elasticsearch and other sources
  3. C.a single timed operation in a distributed trace, with parent/child links forming the trace tree
  4. D.Elasticsearch, Logstash and Kibana — a stack for ingesting, storing and exploring logs

Answer + AI explanation with Pro

8. Which term means: "a single timed operation in a distributed trace, with parent/child links forming the trace tree"?

Mid
  1. A.Sampling
  2. B.Span
  3. C.Langfuse
  4. D.Elastic Stack (ELK)

Answer + AI explanation with Pro

9. Which statement is correct?

Mid
  1. A.Span — passing trace and span IDs across service calls so one request is stitched into a single trace
  2. B.Span — keeping only a fraction of traces (head- or tail-based) to control telemetry volume and cost
  3. C.Span — Elasticsearch, Logstash and Kibana — a stack for ingesting, storing and exploring logs
  4. D.Span — a single timed operation in a distributed trace, with parent/child links forming the trace tree

Answer + AI explanation with Pro

10. What is Trace context propagation?

Mid
  1. A.an LLM-focused observability platform that traces prompts, tokens, cost and latency and runs evals
  2. B.passing trace and span IDs across service calls so one request is stitched into a single trace
  3. C.a vendor-neutral standard and SDK for generating and exporting traces, metrics and logs
  4. D.a visualization tool that builds dashboards over Prometheus, Loki, Elasticsearch and other sources

Answer + AI explanation with Pro

11. Which term means: "passing trace and span IDs across service calls so one request is stitched into a single trace"?

Mid
  1. A.OpenTelemetry
  2. B.Trace context propagation
  3. C.Span
  4. D.Sampling

Answer + AI explanation with Pro

12. Which statement is correct?

Mid
  1. A.Trace context propagation — an LLM-focused observability platform that traces prompts, tokens, cost and latency and runs evals
  2. B.Trace context propagation — a visualization tool that builds dashboards over Prometheus, Loki, Elasticsearch and other sources
  3. C.Trace context propagation — metrics, logs and traces — the complementary signals that together explain system behavior
  4. D.Trace context propagation — passing trace and span IDs across service calls so one request is stitched into a single trace

Answer + AI explanation with Pro

13. What is OTel Collector?

Mid
  1. A.keeping only a fraction of traces (head- or tail-based) to control telemetry volume and cost
  2. B.a visualization tool that builds dashboards over Prometheus, Loki, Elasticsearch and other sources
  3. C.the Elastic Stack UI for searching, visualizing and dashboarding indexed log data
  4. D.a pipeline that receives, processes and exports telemetry, decoupling apps from backends

Answer + AI explanation with Pro

14. Which term means: "a pipeline that receives, processes and exports telemetry, decoupling apps from backends"?

Mid
  1. A.OTel Collector
  2. B.Sampling
  3. C.Elastic Stack (ELK)
  4. D.Span

Answer + AI explanation with Pro

15. Which statement is correct?

Mid
  1. A.OTel Collector — Elasticsearch, Logstash and Kibana — a stack for ingesting, storing and exploring logs
  2. B.OTel Collector — a pipeline that receives, processes and exports telemetry, decoupling apps from backends
  3. C.OTel Collector — an LLM-focused observability platform that traces prompts, tokens, cost and latency and runs evals
  4. D.OTel Collector — a visualization tool that builds dashboards over Prometheus, Loki, Elasticsearch and other sources

Answer + AI explanation with Pro

16. What is Grafana?

Junior
  1. A.a single timed operation in a distributed trace, with parent/child links forming the trace tree
  2. B.Elasticsearch, Logstash and Kibana — a stack for ingesting, storing and exploring logs
  3. C.a vendor-neutral standard and SDK for generating and exporting traces, metrics and logs
  4. D.a visualization tool that builds dashboards over Prometheus, Loki, Elasticsearch and other sources

Answer + AI explanation with Pro

17. Which term means: "a visualization tool that builds dashboards over Prometheus, Loki, Elasticsearch and other sources"?

Junior
  1. A.Sampling
  2. B.Grafana
  3. C.Three pillars
  4. D.Trace context propagation

Answer + AI explanation with Pro

18. Which statement is correct?

Junior
  1. A.Grafana — metrics, logs and traces — the complementary signals that together explain system behavior
  2. B.Grafana — a single timed operation in a distributed trace, with parent/child links forming the trace tree
  3. C.Grafana — a visualization tool that builds dashboards over Prometheus, Loki, Elasticsearch and other sources
  4. D.Grafana — an LLM-focused observability platform that traces prompts, tokens, cost and latency and runs evals

Answer + AI explanation with Pro

19. What is Elastic Stack (ELK)?

Mid
  1. A.Elasticsearch, Logstash and Kibana — a stack for ingesting, storing and exploring logs
  2. B.a vendor-neutral standard and SDK for generating and exporting traces, metrics and logs
  3. C.passing trace and span IDs across service calls so one request is stitched into a single trace
  4. D.an LLM-focused observability platform that traces prompts, tokens, cost and latency and runs evals

Answer + AI explanation with Pro

20. Which term means: "Elasticsearch, Logstash and Kibana — a stack for ingesting, storing and exploring logs"?

Mid
  1. A.Kibana
  2. B.OTel Collector
  3. C.Elastic Stack (ELK)
  4. D.Trace context propagation

Answer + AI explanation with Pro

21. Which statement is correct?

Mid
  1. A.Elastic Stack (ELK) — Elasticsearch, Logstash and Kibana — a stack for ingesting, storing and exploring logs
  2. B.Elastic Stack (ELK) — a vendor-neutral standard and SDK for generating and exporting traces, metrics and logs
  3. C.Elastic Stack (ELK) — a single timed operation in a distributed trace, with parent/child links forming the trace tree
  4. D.Elastic Stack (ELK) — a pipeline that receives, processes and exports telemetry, decoupling apps from backends

Answer + AI explanation with Pro

22. What is Kibana?

Mid
  1. A.keeping only a fraction of traces (head- or tail-based) to control telemetry volume and cost
  2. B.a vendor-neutral standard and SDK for generating and exporting traces, metrics and logs
  3. C.the number of unique label/value combinations in metrics; high cardinality can overwhelm a TSDB
  4. D.the Elastic Stack UI for searching, visualizing and dashboarding indexed log data

Answer + AI explanation with Pro

23. Which term means: "the Elastic Stack UI for searching, visualizing and dashboarding indexed log data"?

Mid
  1. A.Cardinality
  2. B.Span
  3. C.OTel Collector
  4. D.Kibana

Answer + AI explanation with Pro

24. Which statement is correct?

Mid
  1. A.Kibana — keeping only a fraction of traces (head- or tail-based) to control telemetry volume and cost
  2. B.Kibana — the Elastic Stack UI for searching, visualizing and dashboarding indexed log data
  3. C.Kibana — the number of unique label/value combinations in metrics; high cardinality can overwhelm a TSDB
  4. D.Kibana — a pipeline that receives, processes and exports telemetry, decoupling apps from backends

Answer + AI explanation with Pro

25. What is Langfuse?

Mid
  1. A.an LLM-focused observability platform that traces prompts, tokens, cost and latency and runs evals
  2. B.a pipeline that receives, processes and exports telemetry, decoupling apps from backends
  3. C.the Elastic Stack UI for searching, visualizing and dashboarding indexed log data
  4. D.metrics, logs and traces — the complementary signals that together explain system behavior

Answer + AI explanation with Pro

26. Which term means: "an LLM-focused observability platform that traces prompts, tokens, cost and latency and runs evals"?

Mid
  1. A.Langfuse
  2. B.Cardinality
  3. C.Elastic Stack (ELK)
  4. D.OTel Collector

Answer + AI explanation with Pro

27. Which statement is correct?

Mid
  1. A.Langfuse — an LLM-focused observability platform that traces prompts, tokens, cost and latency and runs evals
  2. B.Langfuse — a pipeline that receives, processes and exports telemetry, decoupling apps from backends
  3. C.Langfuse — a vendor-neutral standard and SDK for generating and exporting traces, metrics and logs
  4. D.Langfuse — metrics, logs and traces — the complementary signals that together explain system behavior

Answer + AI explanation with Pro

28. What is Cardinality?

Senior
  1. A.a single timed operation in a distributed trace, with parent/child links forming the trace tree
  2. B.a vendor-neutral standard and SDK for generating and exporting traces, metrics and logs
  3. C.the Elastic Stack UI for searching, visualizing and dashboarding indexed log data
  4. D.the number of unique label/value combinations in metrics; high cardinality can overwhelm a TSDB

Answer + AI explanation with Pro

29. Which term means: "the number of unique label/value combinations in metrics; high cardinality can overwhelm a TSDB"?

Senior
  1. A.Elastic Stack (ELK)
  2. B.Sampling
  3. C.Grafana
  4. D.Cardinality

Answer + AI explanation with Pro

30. Which statement is correct?

Senior
  1. A.Cardinality — the Elastic Stack UI for searching, visualizing and dashboarding indexed log data
  2. B.Cardinality — a visualization tool that builds dashboards over Prometheus, Loki, Elasticsearch and other sources
  3. C.Cardinality — the number of unique label/value combinations in metrics; high cardinality can overwhelm a TSDB
  4. D.Cardinality — a pipeline that receives, processes and exports telemetry, decoupling apps from backends

Answer + AI explanation with Pro

Showing 30 of 33 Observability questions — the full set, with answers, explanations and an AI tutor on every question, is inside.

Free to start

Start with a free readiness check

Sign up free for the 2-minute IT readiness check and a scored result. Answers, explanations and the AI tutor on every Observability question come with Pro.

Take the free IT readiness check

or take a mock interview set up for this area

24,000+ questions & coding problemsSoftware & IT16,274 questionsGovernment jobs26 examsAptitudenew questions every timeAI practice interviewwith feedback65 topics to practiseMechanical1,149 questionsGATE ME9 papersEngineering Mathematics381 questions2-minute checkfreeDSA Problems1,422Civil1,005 questionsGATE CE9 papersCS Fundamentals1,209 questionsYour scores6 skillsSystem Design25Electrical / EEE1,047 questionsGATE EE9 papersRun your codeC++ · Java · PythonLow-Level Design144Electronics & Comm.975 questionsGATE EC9 papersAI help on every questionFull-Stack6,282Chemical1,005 questionsGATE CH9 papersAI whiteboardsystem designWork abroadEurope · remote · transfersESE ME1 paperGATE practice papers2019–2026ESE CE1 paperDate alertsbefore the last dateESE EE1 paperBehavioural courseHR round practiceESE ET1 paperResume optimizerProSSC JE ME1 paperApplication trackerSSC JE CE1 paperCompany-wise prepSSC JE EE1 paperRole roadmapsRRB JE1 subjectPriced in ₹UPI · cardsISRO SC1 paperGATE CS9 papersIBPS SO IT1 paperUGC NET CS1 paperSSC CGL26 papersIBPS PO26 papersRRB NTPC26 papersSSC CHSL26 papersIBPS Clerk26 papersSBI Clerk26 papersRRB Group D26 papersSSC CPO26 papersSSC GD26 papers