Expose Longhorn Dashboard using Traefik Ingress

Identify the Longhorn Dashboard Service

When Longhorn is installed, it comes with a Service called longhorn-frontend. This service manages access to the Longhorn dashboard, which is used for monitoring and managing Longhorn volumes.

You can verify the service by running:

kubectl get svc -n longhorn-system

Look for the longhorn-frontend service in the output, which typically looks like this:

NAME                TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)   AGE
longhorn-frontend   ClusterIP   10.43.75.105   <none>        80/TCP    4m

Create an Ingress Resource to Expose the Dashboard

We will use Traefik Ingress to expose the Longhorn dashboard so that it is accessible via a browser.

Ingress YAML Configuration

Create a YAML file (e.g., longhorn-ingress.yaml) with the following configuration:

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: longhorn-ingress
  namespace: longhorn-system
spec:
  ingressClassName: traefik # We use Traefik as the ingress controller
  rules:
    - host: longhorn.local.host # The domain by which we'll access Longhorn UI
      http:
        paths:
          - path: /
            pathType: Prefix
            backend:
              service:
                name: longhorn-frontend # Service managing Longhorn dashboard
                port:
                  number: 80 # Service port where Longhorn UI runs

This configuration does the following:

• It tells Traefik to expose the longhorn-frontend service (which runs the dashboard) under the host longhorn.local.host.

• HTTP traffic to this host will be routed to the Longhorn dashboard running on port 80.

Apply the Ingress Resource:

After creating the YAML file, apply it to your cluster:

kubectl apply -f longhorn-ingress.yaml

Configure Your /etc/hosts File for Local Access

Since this is for local testing, we need to map the domain longhorn.local.host to the IP address of your Kubernetes cluster. We'll achieve this by updating your /etc/hosts file to resolve requests for longhorn.local.host to your cluster node's IP.

Get the Cluster Node's IP:

Find the IP address of your cluster node (where Traefik or your load balancer is running). You can often use kubectl get nodes -o wide to retrieve the IP address. It might look something like this:

kubectl get nodes -o wide

NAME          STATUS   ROLES                 AGE   VERSION   INTERNAL-IP     EXTERNAL-IP     OS-IMAGE             KERNEL-VERSION   CONTAINER-RUNTIME
node-master   Ready    master,control-plane   12d   v1.22.2   192.168.1.100   <none>          Ubuntu 20.04.3 LTS   5.4.0-89-generic   docker://20.10.8
node-worker   Ready    worker                11d   v1.22.2   192.168.1.101   <none>          Ubuntu 20.04.3 LTS   5.4.0-89-generic   docker://20.10.8

In this example, suppose Traefik is running on the master node, which has the IP 192.168.1.100.

Update /etc/hosts:

Edit the /etc/hosts file on your local machine using a text editor (e.g., vim, nano, etc.).

sudo nano /etc/hosts

Add the following entry, replacing 192.168.1.100 with your node's IP:

192.168.1.100 longhorn.local.host

This entry ensures that when you open http://longhorn.local.host in your browser, it will route the traffic to your cluster.

Access the Longhorn Dashboard

Now that your ingress is configured and your /etc/hosts is updated, you should be able to access the Longhorn dashboard by navigating to:

http://longhorn.local.host

The Longhorn UI should load in your browser, allowing you to manage your Longhorn volumes and nodes.