# Amazon EventBridge integration with AWS X-Ray
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You can use AWS X-Ray to trace [events](eb-events.md) that pass through EventBridge. EventBridge passes the original trace header to the [target](eb-targets.md) so that target services can track, analyze, and debug.

EventBridge can pass a trace header for an event only if the event came from a `PutEvents` request that passed the trace context. X-Ray doesn't trace events that originate from third-party partners, scheduled events, or [AWS services](eb-events.md#eb-service-event), and these event sources don't appear on your X-Ray service map.

X-Ray validates trace headers, and trace headers that aren't valid are dropped. However, the event is still processed.

**Important**  
The trace header is **not** available on the event that's delivered to the invocation target.   
If you have an [event archive](eb-archive-event.md), the trace header isn't available on archived events. If you replay archived events, the trace header isn't included.
If you have a [dead-letter queue (DLQ)](eb-rule-dlq.md), the trace header is included in the `SendMessage` request that sends the event to the DLQ. If you retrieve events (messages) from the DLQ by using `ReceiveMessage`, the trace header associated with the event is included on the Amazon SQS message attribute, but it isn't included in the event message.

For information about how an EventBridge event node connects source and target services, see [Viewing source and targets in the X-Ray service map](https://docs.aws.amazon.com//xray/latest/devguide/xray-services-eventbridge.html#xray-services-eventbridge-service-map) in the *AWS X-Ray Developer Guide*.

You can pass the following trace header information through EventBridge:
+ **Default HTTP header** – The X-Ray SDK automatically populates the trace header as the `X-Amzn-Trace-Id` HTTP header for all invocation targets. To learn more about the default HTTP header, see [Tracing header](https://docs.aws.amazon.com//xray/latest/devguide/xray-concepts.html#xray-concepts-tracingheader) in the *AWS X-Ray Developer Guide*..
+ **`TraceHeader` system attribute** – `TraceHeader` is a [PutEventsRequestEntry attribute](https://docs.aws.amazon.com//eventbridge/latest/APIReference/API_PutEventsRequestEntry.html) reserved by EventBridge to carry the X-Ray trace header to a target. If you also use `PutEventsRequestEntry`, `PutEventsRequestEntry` overrides the HTTP trace header. 

**Note**  
The trace header doesn't count towards the `PutEventsRequestEntry` event size. For more information, see [Calculating PutEvents event entry size](eb-putevents.md#eb-putevent-size).

 The following video demonstrates the use of X-Ray and EventBridge together: