CoreDNS integration for Grafana Cloud

Before you begin

This integration supports CoreDNS version 1.7.0 or greater.

To make metrics available on CoreDNS, both the Prometheus plugin and cache plugin must be enabled.

Install CoreDNS integration for Grafana Cloud

1. In your Grafana Cloud stack, click Connections in the left-hand menu.
2. Find CoreDNS and click its tile to open the integration.
3. Review the prerequisites in the Configuration Details tab and set up Grafana Agent to send CoreDNS metrics to your Grafana Cloud instance.
4. Click Install to add this integration’s pre-built dashboard and alerts to your Grafana Cloud instance, and you can start monitoring your CoreDNS setup.

Configuration snippets for Grafana Alloy

Simple mode

These snippets are configured to scrape a single CoreDNS instance running locally with default ports.

Copy and paste the following snippets into your Grafana Alloy configuration file.

Metrics snippets

river Copy

discovery.relabel "metrics_integrations_integrations_coredns" {
	targets = [{
		__address__ = "localhost:9153",
		cluster     = "cloud",
	}]

	rule {
		target_label = "instance"
		replacement  = constants.hostname
	}
}

prometheus.scrape "metrics_integrations_integrations_coredns" {
	targets    = discovery.relabel.metrics_integrations_integrations_coredns.output
	forward_to = [prometheus.remote_write.metrics_service.receiver]
	job_name   = "integrations/coredns"
}

Advanced mode

The following snippets provide examples to guide you through the configuration process.

To instruct Grafana Alloy to scrape your CoreDNS instances, copy and paste the snippets to your configuration file and follow subsequent instructions.

Advanced metrics snippets

river Copy

discovery.relabel "metrics_integrations_integrations_coredns" {
	targets = [{
		__address__ = "localhost:9153",
		cluster     = "cloud",
	}]

	rule {
		target_label = "instance"
		replacement  = constants.hostname
	}
}

prometheus.scrape "metrics_integrations_integrations_coredns" {
	targets    = discovery.relabel.metrics_integrations_integrations_coredns.output
	forward_to = [prometheus.remote_write.metrics_service.receiver]
	job_name   = "integrations/coredns"
}

To monitor your CoreDNS instance, you must use a discovery.relabel component to discover your CoreDNS Prometheus endpoint and apply appropriate labels, followed by a prometheus.scrape component to scrape it.

Configure the following properties within each discovery.relabel component:

• __address__: The address to your CoreDNS Prometheus metrics endpoint.
• instance label: constants.hostname sets the instance label to your Grafana Alloy server hostname. If that is not suitable, change it to a value uniquely identifies this CoreDNS instance.
• cluster: If you are running on k8s, set this to your k8s cluster name

If you have multiple CoreDNS servers to scrape, configure one discovery.relabel for each and scrape them by including each under targets within the prometheus.scrape component.

Before you begin

This integration supports CoreDNS version 1.7.0 or greater.

To make metrics available on CoreDNS, both the Prometheus plugin and cache plugin must be enabled.

Install CoreDNS integration for Grafana Cloud

1. In your Grafana Cloud stack, click Connections in the left-hand menu.
2. Find CoreDNS and click its tile to open the integration.
3. Review the prerequisites in the Configuration Details tab and set up Grafana Agent to send CoreDNS metrics to your Grafana Cloud instance.
4. Click Install to add this integration’s pre-built dashboard and alerts to your Grafana Cloud instance, and you can start monitoring your CoreDNS setup.

Post-install configuration for the CoreDNS integration

After enabling the prometheus plugins, configure Grafana Agent to scrape your CoreDNS nodes.

CoreDNS exposes a /metrics endpoint. To scrape it, add the provided snippets to your agent configuration file.

Make sure to change targets in the snippet according to your environment.

Configuration snippets for Grafana Agent

Below metrics.configs.scrape_configs, insert the following lines and change the URLs according to your environment:

yaml Copy

    - job_name: integrations/coredns
      relabel_configs:
      - replacement: '<your-instance-name>'
        target_label: instance
      static_configs:
      - targets: ['localhost:9153']
        labels:
          cluster: cloud

Full example configuration for Grafana Agent

Refer to the following Grafana Agent configuration for a complete example that contains all the snippets used for the CoreDNS integration. This example also includes metrics that are sent to monitor your Grafana Agent instance.

yaml Copy

integrations:
  prometheus_remote_write:
  - basic_auth:
      password: <your_prom_pass>
      username: <your_prom_user>
    url: <your_prom_url>
  agent:
    enabled: true
    relabel_configs:
    - action: replace
      source_labels:
      - agent_hostname
      target_label: instance
    - action: replace
      target_label: job
      replacement: "integrations/agent-check"
    metric_relabel_configs:
    - action: keep
      regex: (prometheus_target_sync_length_seconds_sum|prometheus_target_scrapes_.*|prometheus_target_interval.*|prometheus_sd_discovered_targets|agent_build.*|agent_wal_samples_appended_total|process_start_time_seconds)
      source_labels:
      - __name__
  # Add here any snippet that belongs to the `integrations` section.
  # For a correct indentation, paste snippets copied from Grafana Cloud at the beginning of the line.
logs:
  configs:
  - clients:
    - basic_auth:
        password: <your_loki_pass>
        username: <your_loki_user>
      url: <your_loki_url>
    name: integrations
    positions:
      filename: /tmp/positions.yaml
    scrape_configs:
      # Add here any snippet that belongs to the `logs.configs.scrape_configs` section.
      # For a correct indentation, paste snippets copied from Grafana Cloud at the beginning of the line.
metrics:
  configs:
  - name: integrations
    remote_write:
    - basic_auth:
        password: <your_prom_pass>
        username: <your_prom_user>
      url: <your_prom_url>
    scrape_configs:
      # Add here any snippet that belongs to the `metrics.configs.scrape_configs` section.
      # For a correct indentation, paste snippets copied from Grafana Cloud at the beginning of the line.
    - job_name: integrations/coredns
      relabel_configs:
      - replacement: '<your-instance-name>'
        target_label: instance
      static_configs:
      - targets: ['localhost:9153']
        labels:
          cluster: cloud
  global:
    scrape_interval: 60s
  wal_directory: /tmp/grafana-agent-wal