Define processorsedit

Elastic Agent processors are lightweight processing components that you can use to parse, filter, transform, and enrich data at the source. For example, you can use processors to:

  • reduce the number of exported fields
  • enhance events with additional metadata
  • perform additional processing and decoding
  • sanitize data

Each processor receives an event, applies a defined action to the event, and returns the event. If you define a list of processors, they are executed in the order they are defined.

event -> processor 1 -> event1 -> processor 2 -> event2 ...

Elastic Agent processors execute before ingest pipelines, which means that your processor configurations cannot refer to fields that are created by ingest pipelines or Logstash. For more limitations, refer to What are some limitations of using processors?

Where are processors valid?edit

The processors described in this section are valid:

  • Under integration settings in the Integrations UI in Kibana. For example, when configuring an Nginx integration, you can define processors for a specific dataset under Advanced options. The processor in this example adds geo metadata to the Nginx access logs collected by Elastic Agent:

    Screen showing how to add a processor to an integration policy

    Some integrations do not currently support processors.

  • Under input configuration settings for standalone Elastic Agents. For example:

      - type: logfile
        use_output: default
          namespace: default
          - data_stream:
              dataset: nginx.access
              type: logs
            ignore_older: 72h
              - /var/log/nginx/access.log*
              - nginx-access
              - .gz$
              - add_host_metadata:
                  cache.ttl: 5m
                    name: nyc-dc1-rack1
                    location: '40.7128, -74.0060'
                    continent_name: North America
                    country_iso_code: US
                    region_name: New York
                    region_iso_code: NY
                    city_name: New York
              - add_locale: null

You can define processors that apply to a specific input defined in the configuration. Applying a processor to all the inputs on a global basis is currently not supported.

What are some limitations of using processors?edit

Processors have the following limitations.

  • Cannot enrich events with data from Elasticsearch or other custom data sources.
  • Cannot process data after it’s been converted to the Elastic Common Schema (ECS) because the conversion is performed by Elasticsearch ingest pipelines. This means that your processor configuration cannot refer to fields that are created by ingest pipelines or Logstash because those fields are created after the processor runs, not before.
  • May break integration ingest pipelines in Elasticsearch if the user-defined processing removes or alters fields expected by ingest pipelines.
  • If you create new fields via processors, you are responsible for setting up field mappings in the *-@custom component template and making sure the new mappings are aligned with ECS.

What other options are available for processing data?edit

The Elastic Stack provides several options for processing data collected by Elastic Agent. The option you choose depends on what you need to do:

If you need to…​ Do this…​

Sanitize or enrich raw data at the source

Use an Elastic Agent processor

Convert data to ECS, normalize field data, or enrich incoming data

Use ingest pipelines

Define or alter the schema at query time

Use runtime fields

Do something else with your data

Use Logstash plugins

How are Elastic Agent processors different from Logstash plugins or ingest pipelines?edit

Logstash plugins and ingest pipelines both require you to send data to another system for processing. Processors, on the other hand, allow you to apply processing logic at the source. This means that you can filter out data you don’t want to send across the connection, and you can spread some of the processing load across host systems running on edge nodes.