> ## Documentation Index
> Fetch the complete documentation index at: https://docs.coreweave.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Traefik

> Deploy CoreWeave's Traefik Helm chart on CKS for ingress routing and Kubernetes API proxying

| Chart reference     | Description                                                  |
| ------------------- | ------------------------------------------------------------ |
| `coreweave/traefik` | CoreWeave's Helm chart for deploying Traefik on CKS clusters |

## About Traefik

The CoreWeave Traefik Helm chart is based on [the upstream Traefik chart](https://github.com/traefik/traefik-helm-chart). The CoreWeave chart includes additional templating for configurations commonly used in CKS clusters.

The chart's default values are set to work best on the CoreWeave platform. All code examples in this repository assume the default values. If you install the chart with different namespaces or resource names, update the values to match.

## Configuration

The following sections describe the chart's default Ingress behavior and how to enable TLS on Ingresses.

### Ingress DNS

By default, the chart applies a wildcard hostname through a `service.beta.kubernetes.io/external-hostname` annotation:

```text theme={"system"}
service.beta.kubernetes.io/external-hostname: '*'
```

This lets Traefik route to Ingress hosts within the CKS cluster. CKS automatically suffixes the wildcard hostname (`*`) with the appropriate domain name for your cluster. For Services that don't route through Traefik, specific DNS hostnames still take precedence.

To retrieve the applied value at any time, use `kubectl`:

```bash theme={"system"}
kubectl get svc traefik -n traefik -o=jsonpath='{.status.conditions[?(@.type=="ExternalRecords")].message}'
```

<Info>
  For more information on exposing Services, see [How to: Expose a Service](/products/networking/ingress-service/expose-service-dns).
</Info>

### IngressRouteTCP and Kubernetes API proxy

The chart's default values include a [Traefik IngressRouteTCP](https://doc.traefik.io/traefik/routing/providers/kubernetes-crd/#kind-ingressroutetcp) TCP router for your cluster's Kubernetes API server. This Service proxies HTTP traffic to your cluster over [Direct Connect](/products/networking/direct-connect/about-direct-connect) and provides TLS passthrough.

To locate the hostname of this Service, run the following command:

```bash theme={"system"}
kubectl get svc traefik-k8s -n traefik -o=jsonpath='{.status.conditions[?(@.type=="ExternalRecords")].message}'
```

<Warning>
  When you reach the Kubernetes API server over Direct Connect, use the publicly resolvable hostname from the `traefik-k8s` Service, not the private load balancer IP. The API server certificate includes DNS subject alternative names (SANs) but not IP SANs. Connecting by IP causes TLS verification errors.

  For example, `k8s.[CLUSTER-ID].coreweave.app`. This hostname resolves to the private load balancer IP and matches a DNS SAN on the API server certificate.
</Warning>

### Create Ingresses with TLS

<Warning>
  An Ingress with TLS requires `cert-manager` to create and manage the certificates. If you don't have an existing deployment, you can deploy CoreWeave's [cert-manager and its subchart, cert-issuer](/products/cks/clusters/coreweave-charts/cert-manager) for this purpose.
</Warning>

After you deploy the chart, you can use Traefik as the `IngressClass` for a Kubernetes Ingress with TLS. To create the TLS certificate, `cert-manager` uses the `ClusterIssuer` specified by the `cert-manager.io/cluster-issuer` annotation on the `Ingress` object.

## Example chart

In this example manifest, the Ingress uses the default Let's Encrypt `ClusterIssuer` from CoreWeave's [cert-issuer](/products/cks/clusters/coreweave-charts/cert-manager) chart. You can also configure your own TLS certificate solution.

```yaml title="ingress-example.yaml - An example using Traefik with TLS and DNS" highlight={5-7,13-14,27-28} theme={"system"}
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
    # This value must match either the ClusterIssuer created by Traefik,
    # or another pre-existing ClusterIssuer
        cert-manager.io/cluster-issuer: letsencrypt-prod
  name: ingress1
  namespace: namespace1
spec:
  ingressClassName: traefik
  rules:
  # The FQDN used to access this Ingress via the Traefik Service
  - host: &host ingress1.myorg-mycluster.coreweave.app
    http:
      paths:
      - backend:
          service:
            name: my-service
            port:
              number: 80
        path: /
        pathType: Prefix
  tls:
  - hosts:
    - *host
    # This secret will be automatically created for you
    secretName: ingress1-tls
```

<Info>
  For more information on Traefik as a Kubernetes Ingress provider, see [the official Traefik documentation](https://doc.traefik.io/traefik/providers/kubernetes-ingress/).
</Info>