The OpenTelemetry Collector, when configured with a Prometheus receiver, provides an integration with Hashicorp Consul to ingest metrics. The Collector fetches metrics from the configured path in the Consul configuration file and sends it to the Prometheus exporter. From there the metrics are received and processed by the Prometheus receiver and exported to Lightstep Observability.

To complete the integration, you will:

  • Configure Consul to use the Prometheus exporter.
  • Configure the Collector to use the Consul endpoint as a scrape target for the Prometheus receiver.
  • Enable the integration by adding it to a pipeline

Prerequisites

  • Hashicorp Consul v1.8 or later
  • You’ve configured the Collector to export metric data to Lightstep Observability.

Configure Consul reporting

You need to configure Consul to use the Prometheus exporter by setting the native Prometheus endpoint to a retention time greater than 0 and disabling the hostname.

In the Consul configuration file, add the following:

1
2
3
4
telemetry {
  prometheus_retention_time = "60s"
  disable_hostname = true
}

For more details about using Consul with the Prometheus exporter, see the official Consul documentation.

Configure the Collector receiver

In the Collector configuration file, configure the Prometheus receiver to use the Consul endpoint as a scrape target.

1
2
3
4
5
6
7
8
9
10
receivers:
  prometheus:
    config:
      scrape_configs:
        - job_name: 'consul-server'
          metrics_path: '/v1/agent/metrics'
          params:
            format: ['prometheus']
          static_configs:
            - targets: ['localhost:8500']

The OpenTelemetry repo’s readme provides additional details about Prometheus receiver configuration.

Enable the Collector receiver

Once the Consul receiver is configured, enable it by adding it to one or more pipelines as described in the Collector configuration documentation.

Validate metrics are reporting to Lightstep

You can validate that the metrics are reporting to Lightstep from the Metric details section of the Project Settings page.

  1. Open the Project settings page and scroll to the Metric details section.

  2. Search for Consul metric names. Search for metric

    See the Consul docs for a complete list of emitted metrics.
    Note that the metric names will be converted to Prometheus conventions. For example . will be replaced by _, so consul.runtime.alloc_bytes will be renamed to consul_runtime_alloc_bytes.

  3. If needed, click on the metric to edit the description and how the units are displayed in Lightstep.

Create a dashboard for the metrics

Use the Lightstep Terraform Provider to create a dashboard for the metrics.

Additional resources

For a more complete example that’s ready to run, see the Consul integration in Lightstep OpenTelemetry Examples.

Read Hashicorp’s blog post about using OpenTelemetry with Consul.