Name all 12 failure modes from memory. For each one you cannot recall, state the class of system property whose absence allows it.
The Amazon S3 incident involved FM1, FM2, and FM11 acting simultaneously. Explain the causal chain: which failure mode triggered next, and why did FM11 make it worse?
FM7 (Thundering Herd) and FM3 (Unbounded Resource Consumption) frequently compound. Describe the exact mechanism. What infrastructure pattern prevents each, and how do those patterns interact?
A team deploys a schema migration and four hours later discovers that downstream data consumers are writing corrupted records. Identify which failure mode this is, identify which absent principle from F2 allowed it, and describe the simplest change that would have caught it before production.
You are doing a pre-launch review of a new service. The service stores user preferences and is called by six other services. Using the 12 failure modes as a checklist, name the three failure modes with the highest probability of occurring in the first 90 days and explain why.
Concept: F3 — The 12 Failure Modes
Thread: T11 (Feedback) ← Error propagation in algorithms (Book 1) → Incident detection and response (Book 6, Ch 17)
Core Idea: Twelve failure modes — SPOF, Cascading, Unbounded Resources, Data Consistency, Latency Amplification, Hotspotting, Thundering Herd, Schema Violation, Silent Data Corruption, Security Breach, Observability Blindness, Split-Brain — cover the complete taxonomy of distributed system failures. Name the failure mode and the prevention becomes clear.
Tradeoff: Correctness vs Performance (F4 #9) — preventing each failure mode requires a design investment that has a performance or complexity cost; the tradeoff is explicit and worth naming
Failure Mode: FM11 (Observability Blindness) — the failure mode that makes all other failure modes worse, because you cannot fix what you cannot see
Signal: Post-mortem analysis of an incident; pre-deployment review of a new system; architecture review where you want to identify what can go wrong
Maps to: Reference Book Ch 6 (F2 Principles — each failure mode has a corresponding absent principle); Book 4 (every system design chapter uses F3 for failure analysis); Book 6 Ch 4 (failure mode analysis methodology)