opensearch-docs-cn/_data-prepper/pipelines/configuration/processors/trace-peer-forwarder.md

---
layout: default
title: trace_peer_forwarder
parent: Processors
grand_parent: Pipelines
nav_order: 115
---

# trace peer forwarder

The `trace_peer_forwarder` processor is used with [peer forwarder]({{site.url}}{{site.baseurl}}/data-prepper/managing-data-prepper/peer-forwarder/) to reduce by half the number of events forwarded in a [Trace Analytics]({{site.url}}{{site.baseurl}}/data-prepper/common-use-cases/trace-analytics/) pipeline. In Trace Analytics, each event is typically duplicated when it is sent from `otel-trace-pipeline` to `raw-pipeline` and `service-map-pipeline`. When pipelines forward events, this causes the core peer forwarder to send multiple HTTP requests for the same event. You can use `trace peer forwarder` to forward an event once through the `otel-trace-pipeline` instead of `raw-pipeline` and `service-map-pipeline`, which prevents unnecessary HTTP requests.

You should use `trace_peer_forwarder` for Trace Analytics pipelines when you have multiple nodes.

## Usage

To get started with `trace_peer_forwarder`, first configure [peer forwarder]({{site.url}}{{site.baseurl}}/data-prepper/managing-data-prepper/peer-forwarder/). Then create a `pipeline.yaml` file and specify `trace peer forwarder` as the processor. You can configure `peer forwarder` in your `data-prepper-config.yaml` file. For more detailed information, see [Configuring Data Prepper]({{site.url}}{{site.baseurl}}/data-prepper/getting-started/#2-configuring-data-prepper).

See the following example `pipeline.yaml` file: 

```yaml
otel-trace-pipeline:
  delay: "100"
  source:
    otel_trace_source:
  processor:
    - trace_peer_forwarder:
  sink:
    - pipeline:
        name: "raw-pipeline"
    - pipeline:
        name: "service-map-pipeline"
raw-pipeline:
  source:
    pipeline:
      name: "entry-pipeline"
  processor:
    - otel_trace_raw:
  sink:
    - opensearch:
service-map-pipeline:
  delay: "100"
  source:
    pipeline:
      name: "entry-pipeline"
  processor:
    - service_map_stateful:
  sink:
    - opensearch:
```

In the preceding `pipeline.yaml` file, events are forwarded in the `otel-trace-pipeline` to the target peer, and no forwarding is performed in `raw-pipeline` or `service-map-pipeline`. This process helps improve network performance by forwarding events (as HTTP requests) once instead of twice.