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

53 questions in Reliability & Resilience.

Quiz

An airline's crew-scheduling system cannot re-plan fast enough during cascading weather disruption, forcing manual processes that cannot keep up. What signals indicated this risk earlier, and how should such a system be modernised?

A super-app combines messaging, payments, social feeds, mini-programs and notifications in one product used by hundreds of millions daily. What is the dominant reliability risk, and what structural property addresses it?

A workflow executes over days or weeks while individual workers restart many times. How should workflow state, timers, retries, heartbeats and task ownership be designed?

In July 2019 a single regex deployed globally took Cloudflare's network to 100% CPU within seconds. What does this say about how configuration should be released?

Maersk rebuilt roughly 4,000 servers and 45,000 PCs in about ten days after NotPetya in 2017, and recovered its directory only because one data centre had been offline during the attack. What does this say about DR design?

A brief database slowdown caused a two-hour full outage. Explain the likely amplification chain and the fixes at each stage.

A travel platform depends on hundreds of external suppliers with varying reliability. How should resilience testing be designed when the failures originate outside the system?

How would you test that your service degrades correctly when a dependency's latency rises tenfold?

Review this resilience programme. Chaos experiments run weekly in staging at 03:00, they inject only instance termination, results are recorded in a spreadsheet, and there is a kill switch that has never been used. What would you change, and what would you keep?

A collaborative workspace product must define RTO and RPO. The product team says "we can never lose a user's work". What does that requirement actually mean, and what does it cost?

A stakeholder asks for zero RPO across the estate. What does that cost and what would you propose instead?

In April 2022 a maintenance script at Atlassian used the wrong identifiers and deleted sites belonging to about 775 customers. Restoration took up to about two weeks for some of them, even though backups existed and were working. What property of the recovery design accounts for that gap?