EventBridge Fundamentals
Explore how Amazon EventBridge handles event routing through event buses, rule evaluation, and target invocation. Learn troubleshooting strategies by analyzing event patterns, rule configurations, and target execution to pinpoint failures accurately and maintain reliable event-driven operations.
A remediation that should have fired but didn’t creates a frustrating kind of uncertainty. The failure can originate in two very different places: the routing logic that determines whether an event matches, or the execution path that carries out the action after a match. Guessing which side is responsible wastes time. The better approach is to use evidence to pinpoint exactly where the chain stopped.
In Amazon EventBridge, the minimal flow consists of an event bus that receives an event, a rule that evaluates the event against a pattern, and a target that performs the action when the rule matches. Troubleshooting should establish what happened at each stage using evidence from EventBridge and the downstream service rather than assumptions about what should have happened.
The topology below provides a starting point for the investigation. Each stage has its own confirmation signal and its own characteristic failure symptoms, making it possible to narrow the problem down systematically.
When the event producer publishes, EventBridge either accepts the event on the bus or it does not. When EventBridge evaluates rules, each rule either matches the event pattern or it does not. When a rule matches, EventBridge attempts to invoke each configured target, and that invocation can succeed, be rejected by permissions, or fail due to target-side errors.
Trace the event
An event becomes routable when its envelope fields are consistent enough for a rule pattern to match. A typical event shape includes source, detail-type, and detail, and the rule pattern selects on those fields so EventBridge can decide whether to fan out to targets. ... ...