OpenTelemetry

An input plugin to ingest OpenTelemetry logs, metrics, and traces

The OpenTelemetry input plugin lets you receive data based on the OpenTelemetry specification from various OpenTelemetry exporters, the OpenTelemetry Collector, or the Fluent Bit OpenTelemetry output plugin.

Fluent Bit has a compliant implementation which fully supports OTLP/HTTP and OTLP/GRPC. The single port configured defaults to 4318 and supports both transport methods.

Configuration

Key	Description	Default
listen	The network address to listen on.	0.0.0.0
port	The port for Fluent Bit to listen for incoming connections. In Fluent Bit 3.0.2 or later, this port is used for both transport OTLP/HTTP and OTLP/GRPC.	4318
tag	Tag for all data ingested by this plugin. This will only be used if tag_from_uri is set to false. Otherwise, the tag will be created from the URI.	none
tag_key	Specify the key name to overwrite a tag. If set, the tag will be overwritten by a value of the key.	none
raw_traces	Route trace data as a log.	false
buffer_max_size	Specify the maximum buffer size in KB, MB, or GB to the HTTP payload.	4M
buffer_chunk_size	Initial size and allocation strategy to store the payload (advanced users only)`	512K
successful_response_code	Allows for setting a successful response code. Supported values: 200, 201, or 204.	201
tag_from_uri	By default, the tag will be created from the URI. For example, v1_metrics from /v1/metrics. This must be set to false if using tag.	true
threaded	Indicates whether to run this input in its own thread.	false

Raw traces means that any data forwarded to the traces endpoint (/v1/traces) will be packed and forwarded as a log message, and won't be processed by Fluent Bit. The traces endpoint by default expects a valid protobuf encoded payload, but you can set the raw_traces option in case you want to get trace telemetry data to any of the Fluent Bit supported outputs.

OpenTelemetry transport protocol endpoints

Fluent Bit exposes the following endpoints for data ingestion based on the OpenTelemetry protocol:

For OTLP/HTTP:

• Logs

  • /v1/logs

• Metrics

  • /v1/metrics

• Traces

  • /v1/traces

For OTLP/GRPC:

• Logs

  • /opentelemetry.proto.collector.log.v1.LogService/Export

  • /opentelemetry.proto.collector.log.v1.LogService/Export

• Metrics

  • /opentelemetry.proto.collector.metric.v1.MetricService/Export

  • /opentelemetry.proto.collector.metrics.v1.MetricsService/Export

• Traces

  • /opentelemetry.proto.collector.trace.v1.TraceService/Export

  • /opentelemetry.proto.collector.traces.v1.TracesService/Export

Get started

The OpenTelemetry input plugin supports the following telemetry data types:

Type	HTTP1/JSON	HTTP1/Protobuf	HTTP2/GRPC
Logs	Stable	Stable	Stable
Metrics	Unimplemented	Stable	Stable
Traces	Unimplemented	Stable	Stable

A sample configuration file to get started will look something like the following:

fluent-bit.yaml

pipeline:
  inputs:
    - name: opentelemetry
      listen: 127.0.0.1
      port: 4318
      
  outputs:
    - name: stdout
      match: '*'

fluent-bit.conf

[INPUT]
  name opentelemetry
  listen 127.0.0.1
  port 4318

[OUTPUT]
  name stdout
  match *

With this configuration, Fluent Bit listens on port 4318 for data. You can now send telemetry data to the endpoints /v1/metrics for metrics, /v1/traces for traces, and /v1/logs for logs.

A sample curl request to POST JSON encoded log data would be:

curl --header "Content-Type: application/json" --request POST --data '{"resourceLogs":[{"resource":{},"scopeLogs":[{"scope":{},"logRecords":[{"timeUnixNano":"1660296023390371588","body":{"stringValue":"{\"message\":\"dummy\"}"},"traceId":"","spanId":""}]}]}]}'   http://0.0.0.0:4318/v1/logs