Prometheus Remote Write Exporter

Status
Stability	beta
Supported pipeline types	metrics
Distributions	core, contrib

Prometheus Remote Write Exporter sends OpenTelemetry metrics to Prometheus remote write compatible backends such as Cortex, Mimir, and Thanos. By default, this exporter requires TLS and offers queued retry capabilities.

⚠️ Non-cumulative monotonic, histogram, and summary OTLP metrics are dropped by this exporter.

A design doc is available to document in detail how this exporter works.

Getting Started

The following settings are required:

• endpoint (no default): The remote write URL to send remote write samples.

By default, TLS is enabled and must be configured under tls::

• insecure (default = false): whether to enable client transport security for the exporter's connection.

As a result, the following parameters are also required under tls::

• cert_file (no default): path to the TLS cert to use for TLS required connections. Should only be used if insecure is set to false.
• key_file (no default): path to the TLS key to use for TLS required connections. Should only be used if insecure is set to false.

The following settings can be optionally configured:

• external_labels: map of labels names and values to be attached to each metric data point
• headers: additional headers attached to each HTTP request.
  • Note the following headers cannot be changed: Content-Encoding, Content-Type, X-Prometheus-Remote-Write-Version, and User-Agent.
• namespace: prefix attached to each exported metric name.
• remote_write_queue: fine tuning for queueing and sending of the outgoing remote writes.
  • enabled: enable the sending queue
  • queue_size: number of OTLP metrics that can be queued. Ignored if enabled is false
  • num_consumers: minimum number of workers to use to fan out the outgoing requests.
• resource_to_telemetry_conversion
  • enabled (default = false): If enabled is true, all the resource attributes will be converted to metric labels by default.
• target_info: customize target_info metric
  • enabled (default = true): If enabled is true, a target_info metric will be generated for each resource metric (see open-telemetry/opentelemetry-specification#2381).

Example:

exporters:
  prometheusremotewrite:
    endpoint: "https://my-cortex:7900/api/v1/push"
    wal: # Enabling the Write-Ahead-Log for the exporter.
      directory: ./prom_rw # The directory to store the WAL in
      buffer_size: 100 # Optional count of elements to be read from the WAL before truncating; default of 300
      truncate_frequency: 45s # Optional frequency for how often the WAL should be truncated. It is a time.ParseDuration; default of 1m
    resource_to_telemetry_conversion:
      enabled: true # Convert resource attributes to metric labels

Example:

exporters:
  prometheusremotewrite:
    endpoint: "https://my-cortex:7900/api/v1/push"
    external_labels:
      label_name1: label_value1
      label_name2: label_value2

Advanced Configuration

Several helper files are leveraged to provide additional capabilities automatically:

• HTTP settings
• TLS and mTLS settings
• Retry and timeout settings, note that the exporter doesn't support sending_queue but provides remote_write_queue.

Metric names and labels normalization

OpenTelemetry metric names and attributes are normalized to be compliant with Prometheus naming rules. Details on this normalization process are described in the Prometheus translator module.