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Quiz

2667 questions of the kind that actually get asked — in interviews, in architecture review boards, and by the person who has to run the thing at 3 AM. Every answer states the trade-off rather than the slogan, and says when the obvious choice is the wrong one.

All areas2667 Architecture Fundamentals81 Distributed Systems101 Data Architecture90 Cloud Architecture87 Networking86 API & Integration Architecture78 Reliability & Resilience88 Observability81 Performance & Capacity Engineering90 Security Architecture95 Cost Architecture & FinOps92 Business Architecture93 Architecture Communication91 Enterprise Architecture91 Legacy Modernization92 AI-Era Architecture86 Software Architecture & Engineering84 Architecture Patterns84 Architecture Decision-Making91 The Architect's Meta-Skills92 Delivery & Release Engineering93 Platform Engineering & Developer Experience92 Testing & Quality Architecture90 Data Platform Architecture88 Streaming & Real-Time Data93 Data Governance & Semantics81 Frontend & Experience Architecture91 Edge, Mobile & IoT88 Regulatory & Data Protection Architecture90 Assurance, Audit & Model Risk88
Difficulty Any beginner intermediate advanced

42 questions in Observability.

  1. Alert Fatigue advanced

    Your team receives 200 pages a week and the on-call rotation has lost two engineers in six months. Fix it.

    2 min answer alertingon-callburn-rateculture
  2. Alerting advanced

    Error rate has been 1.5% for three days. No alert fired. Customers are complaining. What is happening and what failed?

    2 min answer gray-failurealertingoutliersdetection
  3. Application Performance Monitoring advanced

    In a multi-tenant platform, aggregate application performance metrics look healthy while specific tenants experience severe slowness. What must performance monitoring do differently?

    2 min answer apmmulti-tenancysegmentationoutliers
  4. Application Performance Monitoring advanced

    Review this instrumentation. A checkout service emits about 400 spans per request, every span carries roughly 30 attributes including the full request body, tracing runs at 100% with no sampling, and the team reports that they cannot find anything in the traces. What would you remove, what would you change, and what would you keep even though it looks excessive?

    3 min answer tracingapminstrumentationsampling
  5. Business Metrics advanced

    Customers reported an outage 40 minutes before your monitoring did. How do you close that gap?

    2 min answer detectionbusiness-metricssyntheticsclient-side
  6. Cardinality advanced Multiple choice

    A live-streaming platform of Twitch's shape needs usable latency quantiles for 300 API endpoints whose responses span 2 ms to 90 seconds. The current histograms use 12 fixed buckets topping out at 10 seconds and every p99 above that reads as the overflow bucket. Which change fits the problem?

    3 min answer cardinalityhistogramsopentelemetryquantiles
  7. Cardinality advanced

    A single deploy took down your monitoring platform. What happened, and how do you prevent a recurrence?

    2 min answer cardinalitymetricscostguardrails
  8. Cardinality advanced

    A team wants to debug failures nobody predicted, using wide high-cardinality events rather than pre-aggregated metrics. How does the storage design differ, and how must sampling preserve rare errors?

    3 min answer honeycombwide-eventscardinalitysampling
  9. Cardinality advanced

    An observability platform ingests billions of telemetry events daily, and some customers attach dimensions with unbounded distinct values. How should ingestion, storage, indexing and query be designed so cost and latency stay manageable?

    2 min answer cardinalitytime-seriesingestionmulti-tenancy
  10. Cardinality advanced

    An observability platform ingests enormous telemetry volume, but a small number of dimensions create extreme cardinality. How should ingestion, aggregation, indexing, sampling, retention and storage tiers be designed so cost and query performance stay predictable?

    2 min answer grafanacardinalitytelemetry-costretention
  11. Debugging Distributed Systems advanced

    A collaborative editing platform receives a report that one document occasionally shows different content to different users, but it cannot be reproduced. How do you investigate a rare, non-deterministic, distributed bug?

    2 min answer debuggingnon-determinismdistributedforensics
  12. Debugging Distributed Systems advanced

    A platform of 40 services has logs only, and incidents take hours to diagnose. Design the observability strategy and its rollout order.

    2 min answer observabilitytracingmetricsrollout