An EventBridge rule is enabled and its target is healthy, but the target never runs. A real event from the application was captured. What should be compared to explain the miss?
Select an answer to reveal the explanation.
Short Explanation
You’ve confirmed the rule is enabled and the target is healthy, so compare the captured event with the rule’s event pattern: a required field that doesn’t match can keep the target from running. EventBridge delivery is not confined by a subnet route table or blocked by the VPC default security group, and an event-pattern rule does not also need a schedule.
Full Explanation
An EventBridge rule invokes its target only when an event matches the rule’s event pattern. The rule is enabled, the target is healthy, and a real event was captured, so compare that event with the pattern to explain why the target never runs. A field required by the pattern that is absent or has a different value is enough for the event not to match, and the target is skipped. A subnet route table is not the path by which EventBridge delivers an event to a rule; the event does not have to be routed inside one subnet to reach the rule. The VPC default security group does not sit in front of the event bus and drop events before pattern evaluation. A schedule expression is used for a scheduled rule; an event-pattern rule does not also need a schedule, and adding one will not make this event match. Caveat: even a correct pattern will not see an event published to a different event bus from the one the rule uses. Practical check: test the captured event against the pattern, adjust any mismatched field, and confirm that the next real event invokes the target.