Enable external access to Grafana Mimir

Set up external access to Grafana Mimir to allow writing and quering metrics from outside the Kubernetes cluster. You can set up an ingress that enables you to externally access a Kubernetes cluster.

Before you begin

Verify that an ingress controller is set up in the Kubernetes cluster, for example ingress-nginx

Set up ingress

Configure an ingress:
b. Add the following to your custom.yaml Helm values file:
yaml
```
nginx:
  ingress:
    enabled: true
    ingressClassName: nginx
    hosts:
      - host: <ingress-host>
        paths:
          - path: /
            pathType: Prefix
    tls:
      # empty, disabled.
```
Replace <ingress-host> with a suitable hostname that DNS can resolve to the external IP address of the Kubernetes cluster. For more information, refer to Ingress.
Note: On Linux systems, and if it is not possible for you set up local DNS resolution, you can use the --add-host=<ingress-host>:<kubernetes-cluster-external-address> command-line flag to define the <ingress-host> local address for the docker commands in the examples that follow.
Note: To see all of the configurable parameters for a Helm chart installation, use helm show values grafana/mimir-distributed.
Upgrade Grafana Mimir by using the helm command:
bash
```
helm -n mimir-test upgrade mimir grafana/mimir-distributed -f custom.yaml
```
The output of the command should contain the URL to use for querying Grafana Mimir from the outside, for example:
bash
```
From outside the cluster via ingress:
http://myhost.mynetwork/prometheus
```

Configure Prometheus to write to Grafana Mimir

You can either configure Prometheus to write to Grafana Mimir or configure Grafana Alloy to write to Mimir. Although you can configure both, you don’t need to.

Make a choice based on whether or not you already have a Prometheus server set up:

For an existing Prometheus server:
1. Add the following YAML snippet to your Prometheus configuration file:
  yaml
```
remote_write:
  - url: http://<ingress-host>/api/v1/push
```
  In this case, your Prometheus server writes metrics to Grafana Mimir, based on what is defined in the existing scrape_configs configuration.
2. Restart the Prometheus server.
For a Prometheus server that does not exist yet:
1. Write the following configuration to a prometheus.yml file:
  yaml
```
remote_write:
  - url: http://<ingress-host>/api/v1/push

scrape_configs:
  - job_name: prometheus
    honor_labels: true
    static_configs:
      - targets: ["localhost:9090"]
```
  In this case, your Prometheus server writes metrics to Grafana Mimir that it scrapes from itself.
2. Start a Prometheus server by using Docker:
  bash
```
docker run -p 9090:9090  -v <absolute-path-to>/prometheus.yml:/etc/prometheus/prometheus.yml prom/prometheus
```
  Note: On Linux systems, if <ingress-host> cannot be resolved by the Prometheus server, use the additional command-line flag --add-host=<ingress-host>:<kubernetes-cluster-external-address> to set it up.

Configure Grafana Alloy to write to Grafana Mimir

You can either configure Grafana Alloy to write to Grafana Mimir or configure Prometheus to write to Mimir. Although you can configure both, you don’t need to.

Make a choice based on whether you already have Alloy set up:

For an existing Alloy:
1. Add the following configuration snippet for the prometheus.remote_write component to your Alloy configuration file:
```
prometheus.remote_write "LABEL" {
  endpoint {
    url = http://<ingress-host>/api/v1/push
  }
}
```
2. Add forward_to = [prometheus.remote_write.LABEL.receiver] to an existing pipeline.
3. Restart Alloy.

For a new Alloy:

Write the following configuration to a config.alloy file:

prometheus.exporter.self "self_metrics" {
}

prometheus.scrape "self_scrape" {
  targets    = prometheus.exporter.self.self_metrics.targets
  forward_to = [prometheus.remote_write.mimir.receiver]
}

prometheus.remote_write "mimir" {
  endpoint {
    url = "http://<ingress-host>/api/v1/push"
  }
}

Start Alloy by using Docker:
bash
```
docker run -v <absolute-path-to>/config.alloy:/etc/alloy/config.alloy -p 12345:12345 grafana/alloy:latest run --server.http.listen-addr=0.0.0.0:12345 --storage.path=/var/lib/alloy/data /etc/alloy/config.alloy
```
Note: On Linux systems, if <ingress-host> cannot be resolved by Alloy, use the additional command-line flag --add-host=<ingress-host>:<kubernetes-cluster-external-address> to set it up.

For more information about the prometheus.remote_write component, refer to prometheus.remote_write in the Grafana Alloy documentation.

Query metrics in Grafana

You can use the Grafana installed in Kubernetes in the Start Grafana in Kubernetes and query metrics documentation, or follow the instructions below.

Note: If you have the port-forward running for Grafana from an earlier step, stop it.

First install Grafana, and then add Mimir as a Prometheus data source.

Start Grafana by using Docker:
bash
```
docker run --rm --name=grafana -p 3000:3000 grafana/grafana
```
Note: On Linux systems, if <ingress-host> cannot be resolved by Grafana, use the additional command-line flag --add-host=<ingress-host>:<kubernetes-cluster-external-address> to set it up.
In a browser, go to the Grafana server at http://localhost:3000.
Sign in using the default username admin and password admin.
On the left-hand side, go to Configuration > Data sources.
Configure a new Prometheus data source to query the local Grafana Mimir cluster, by using the following settings:
Field Value
Name Mimir
URL http://<ingress-host>/prometheus
To add a data source, refer to Add a data source.
Verify success:
You should be able to query metrics in Grafana Explore, as well as create dashboard panels by using your newly configured Mimir data source. For more information, refer to Monitor Grafana Mimir.