What is EventBridge, and how does it differ from SNS?
AWS · Advanced level
Answer
EventBridge is an event bus with filtering, routing, schedules, SaaS integrations, archives, and replay. SNS is simpler pub/sub fan-out; I use EventBridge for event-driven architecture routing and SNS for straightforward notification fan-out.
Technical explanation
EventBridge is better for event routing and governance; SNS is simpler for pub/sub fan-out.
Messaging services decouple producers and consumers, but the reliability model depends on ordering, retries, DLQs, idempotency, batching, and backpressure.
At-least-once delivery means consumers must safely handle duplicate messages unless the business can tolerate duplicates.
Monitor queue depth, age of oldest message, DLQ count, consumer errors, throttles, and downstream saturation.
Hands-on example
1. Create a small producer and consumer using the relevant service - SQS, SNS, or EventBridge.
2. Add retry, DLQ, visibility timeout or event rule configuration, and idempotency key handling.
3. Inject duplicate messages, consumer failure, and downstream throttling to observe retry and backpressure behavior.
4. Alarm on age, DLQ count, failed deliveries, throttles, and consumer error rate.
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