통신 패턴을 위한 카오스 엔지니어링

Chaos engineering is the practice of deliberately injecting failures into a system to verify it behaves as designed. You do not learn whether your circuit breaker works by hoping; you prove it by breaking things on purpose.

You have built sagas, circuit breakers, retries, and bulkheads. Chaos engineering is how you validate all of them together under realistic failure, before a real outage does it for you.

Every experiment starts with a hypothesis about steady state. For example: 'If the payment service becomes unavailable, the circuit breaker opens and the order saga compensates within 5 seconds.'

Pick measurable signals that represent a healthy system: success rate, latency, queue depth. The experiment passes if these stay within bounds despite the injected failure.

Typical experiments:

• Kill a service instance
• Add latency to a dependency
• Drop or duplicate messages
• Partition the network
• Exhaust CPU or memory

Adding artificial delay tests timeouts and bulkheads. Here is the idea in miniature.

Start small. Run experiments on a single instance or a small percentage of traffic before going wider. A controlled experiment must not become an uncontrolled incident.

Always be able to stop the experiment instantly. If steady state degrades beyond your threshold, halt injection and let the system recover.

A game day is a scheduled, team-wide chaos exercise. Engineers practice responding to failures, validate runbooks, and find gaps in observability, all in a controlled setting.

Begin in staging to build confidence, then graduate carefully to production, where real traffic and real dependencies reveal problems staging never will. Mature teams run continuous, automated chaos.

Whether the hypothesis holds or fails, you learn. A failed hypothesis is a fixed weakness before it became an outage. Feed findings back into design, thresholds, and runbooks.

What is the single most important safety practice when running a chaos experiment in production?

You learned chaos engineering:

• Inject failures deliberately to validate resilience patterns.
• Form a hypothesis around steady state.
• Limit blast radius and keep an abort switch.
• Use game days and graduate from staging to production.

Chaos engineering proves your saga and circuit breaker work before reality tests them.