Configuring the OpenTelemetry Collector

You can deploy an OpenTelemetry Collector for TAS for VMs to egress metrics.

When the OpenTelemetry (OTel) Collector is deployed, the Loggregator Forwarder Agent forwards platform and application metrics to the OTel Collector, which then egresses metrics using one or more metric exporters that you configure.

Caution OpenTelemetry Collector is currently an experimental feature and should not be used in production systems.

Metric Exporter configuration

The OTel Collector has a standard YAML-based file format for configuration. When deploying TAS for VMs with Otel Collector support, provide only the exporter configuration.

Important Specify only the configuration under the exporters section of the OpenTelemetry Collector configuration. It is not currently possible to configure Receivers or Processors.

For example, to configure the OpenTelemetry Collector to egress metrics using OTLP over gRPC, you can provide the following minimal configuration. This will use the defaults for gRPC and TLS configuration.

otlp:
  endpoint: 203.0.113.10:4317

As the OTel Collector is typically deployed on all VMs, you must ensure that all VMs in your deployment are allowed to connect to the OTLP server endpoint.

mTLS

To configure the exporter to use an mTLS connection to the remote OTLP endpoint, you can specify additional TLS configuration.

otlp:
  endpoint: 203.0.113.10:4317
  tls:
    cert_pem: |
      PEM_ENCODED_CERTIFICATE
    key_pem: |
      PEM_ENCODED_CERTIFICATE
    ca_pem: |
      PEM_ENCODED_CERTIFICATE

gRPC compression

You can configure the type of compression used for OTLP gRPC exporters. The OTLP gRPC exporter uses gzip compression by default. To reduce CPU usage of the OTel Collector (increasing the size of the payload) you can optionally configure the OTLP gRPC exporter to use snappy compression. Validate that the server you are sending metrics to support snappy compression before making this change.

otlp:
  endpoint: 203.0.113.10:4317
  compression: snappy

Multiple exporters

The OTel Collector supports defining multiple exporters, each with its own configuration. For example, you can define two OTLP gRPC exporters that egress metrics to different destinations.

otlp:
  endpoint: 203.0.113.10:4317
otlp/another:
  endpoint: 203.0.113.11:4317

Authentication

The TAS for VMs distribution of the OpenTelemetry Collector does not support configuration of authenticator extensions for exporters at this time.

Reviewing the available exporters

The TAS for VMs distribution of the OpenTelemetry Collector ships with a number of exporters. To see the exporters that are available for use, run the following command on a VM that has otel-collector deployed.

/var/vcap/packages/otel-collector/otel-collector components

Deploying the OpenTelemetry Collector

Under the System Logging tab, you can configure the metric exporters in the OpenTelemetry Collector Metric Exporters (beta) field. Enter the metric exporter YAML configuration into that text box.