Chaos Engineering

Overview It’s 2 AM. Your phone screams. The monitoring dashboard is a sea of red — core transaction P99 latency just hit 8 seconds, upstream services are timing out and circuit-breaking, and customer support chat is flooding with screenshots. You’re VPN-ing in while your brain runs at full speed: have we seen this scenario in a drill? Is it covered in the runbook? Do I remember the failover steps? If you’re still searching the wiki for documentation at this moment, it means one thing: your runbook was written but never practiced....

Reliability Engineering: More Than Just “Not Breaking” The goal of reliability engineering is not to pursue zero failures — that’s neither realistic nor economical. The real goal is: given that failures are inevitable, make the system capable of fast detection, automatic recovery, and continuous learning. Google SRE proposes a core formula: MTTR << MTBF / (MTBF + MTTR) × (1 - SLO) This formula reveals a key insight: when the time between failures (MTBF) is much greater than the repair time (MTTR), system availability naturally approaches the SLO target....

Overview The traditional approach to reliability is “try not to have failures” — add monitoring, add alerts, add redundancy. But this passive defense has a fundamental flaw: you don’t know how the system actually behaves during a failure until one actually occurs. Chaos engineering takes the opposite approach: proactively and controllably inject failures to discover system weaknesses before they become incidents. It’s not about causing destruction — it’s a scientific experimental method: form a hypothesis (“the system should be able to withstand a node failure”), design an experiment (kill a node), verify the hypothesis (is the service still working?...