---
title: "CoreDNS integration | Grafana Cloud documentation"
description: "Learn about CoreDNS Grafana Cloud integration."
---

> For a curated documentation index, see [llms.txt](/llms.txt). For the complete documentation index, see [llms-full.txt](/llms-full.txt).

# CoreDNS integration for Grafana Cloud

CoreDNS is a fast and efficient DNS server written in Go, that chains plugins, where each plugin performs a (DNS) function.

This integration includes 9 useful alerts and 1 pre-built dashboard to help monitor and visualize CoreDNS metrics.

## Before you begin

This integration supports CoreDNS version 1.7.0 or greater.

To make metrics available on CoreDNS, both the [Prometheus plugin](https://coredns.io/plugins/metrics) and [cache plugin](https://coredns.io/plugins/cache) 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 Alloy 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.

First, **manually** copy and append the following snippets into your alloy configuration file.

### Metrics snippets

Alloy ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

```alloy
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, **manually** copy and append the snippets to your alloy configuration file, then follow subsequent instructions.

### Advanced metrics snippets

Alloy ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

```alloy
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](/docs/alloy/latest/reference/components/discovery.relabel/) component to discover your CoreDNS Prometheus endpoint and apply appropriate labels, followed by a [prometheus.scrape](/docs/alloy/latest/reference/components/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.

## Kubernetes instructions

Instructions for Kubernetes

### Before you begin with Kubernetes

**Please note**: These instructions assume the use of the [Kubernetes Monitoring Helm chart](https://github.com/grafana/k8s-monitoring-helm)

This integration supports CoreDNS version 1.7.0 or greater.

To make metrics available on CoreDNS, both the [Prometheus plugin](https://coredns.io/plugins/metrics) and [cache plugin](https://coredns.io/plugins/cache) must be enabled.

### Configuration snippets for Kubernetes Helm chart

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

To scrape your CoreDNS instances, **manually** modify your Kubernetes Monitoring Helm chart with these configuration snippets.

Replace any values between the angle brackets `<>` in the provided snippets with your desired configuration values.

#### Metrics snippets

Alloy ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

```alloy
alloy-metrics:
    extraConfig: |-
        discovery.kubernetes "coredns" {
            role = "pod"
            selectors {
                role = "pod"
                label = "<coredns_pod_label_name>=<coredns_pod_label_value>"
            }
        }
        
        discovery.relabel "coredns" {
            targets = discovery.kubernetes.coredns.targets
            rule {
                source_labels = ["__meta_kubernetes_pod_container_port_number"]
                regex = "<coredns_prometheus_port_number>"
                action = "keep"
            }  
            rule {
                source_labels = ["__meta_kubernetes_pod_name"]
                target_label = "instance"
            }
        }

        prometheus.scrape "coredns" {
            targets      = discovery.relabel.coredns.output
            job_name     = "integrations/tensorflow"
            honor_labels = true
        }
```

## Dashboards

The CoreDNS integration installs the following dashboards in your Grafana Cloud instance to help monitor your system.

- CoreDNS

**CoreDNS dashboard**

## Alerts

The CoreDNS integration includes the following useful alerts:

**coredns**

Expand table

| Alert              | Description                                                         |
|--------------------|---------------------------------------------------------------------|
| CoreDNSDown        | Critical: CoreDNS has disappeared from Prometheus target discovery. |
| CoreDNSLatencyHigh | Critical: CoreDNS is experiencing high 99th percentile latency.     |
| CoreDNSErrorsHigh  | Critical: CoreDNS is returning SERVFAIL.                            |
| CoreDNSErrorsHigh  | Warning: CoreDNS is returning SERVFAIL.                             |

**coredns\_forward**

Expand table

| Alert                                 | Description                                                          |
|---------------------------------------|----------------------------------------------------------------------|
| CoreDNSForwardLatencyHigh             | Critical: CoreDNS is experiencing high latency forwarding requests.  |
| CoreDNSForwardErrorsHigh              | Critical: CoreDNS is returning SERVFAIL for forward requests.        |
| CoreDNSForwardErrorsHigh              | Warning: CoreDNS is returning SERVFAIL for forward requests.         |
| CoreDNSForwardHealthcheckFailureCount | Warning: CoreDNS health checks have failed to upstream server.       |
| CoreDNSForwardHealthcheckBrokenCount  | Warning: CoreDNS health checks have failed for all upstream servers. |

## Metrics

The most important metrics provided by the CoreDNS integration, which are used on the pre-built dashboard and Prometheus alerts, are as follows:

- coredns\_build\_info
- coredns\_cache\_entries
- coredns\_cache\_hits\_total
- coredns\_cache\_misses\_total
- coredns\_dns\_request\_duration\_seconds\_bucket
- coredns\_dns\_request\_size\_bytes\_bucket
- coredns\_dns\_requests\_total
- coredns\_dns\_response\_size\_bytes\_bucket
- coredns\_dns\_responses\_total
- coredns\_forward\_healthcheck\_broken\_total
- coredns\_forward\_healthcheck\_failures\_total
- coredns\_forward\_request\_duration\_seconds\_bucket
- coredns\_forward\_requests\_total
- coredns\_forward\_responses\_total
- coredns\_panics\_total
- coredns\_plugin\_enabled
- go\_goroutines
- process\_cpu\_seconds\_total
- process\_resident\_memory\_bytes
- up

## Changelog

md ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

```md
# 1.0.0 - December 2025

* Chore: Fix incorrect semver to 1.0.0. No further changes

# 0.0.7 - September 2023

* New Filter Metrics option for configuring the Grafana Agent, which saves on metrics cost by dropping any metric not used by this integration. Beware that anything custom built using metrics that are not on the snippet will stop working.
* New hostname relabel option, which applies the instance name you write on the text box to the Grafana Agent configuration snippets, making it easier and less error prone to configure this mandatory label.

# 0.0.6 - August 2023

- Fix coredns alerts variable not found error

# 0.0.5 - July 2023

- Added Grafana Agent Operator configuration snippet to support CoreDNS in a kubernetes cluster
- Added cluster selector to dashboard for kubernetes support
- Added default cluster label to agent config

# 0.0.4 - April 2023

- Update alerts to include external labels

# 0.0.3 - January 2023

- Update to latest integration structure
- Update to latest upstream mixin

# 0.0.2 - October 2021

- Update mixin to latest version

# 0.0.1 - May 2021

- Initial release
```

## Cost

By connecting your CoreDNS instance to Grafana Cloud, you might incur charges. To view information on the number of active series that your Grafana Cloud account uses for metrics included in each Cloud tier, see [Active series and dpm usage](/docs/grafana-cloud/fundamentals/active-series-and-dpm/) and [Cloud tier pricing](/products/cloud/pricing/).