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About Traefik

The CoreWeave Traefik Helm chart is based on the upstream Traefik 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:
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:
For more information on exposing Services, see How to: Expose a Service.

IngressRouteTCP and Kubernetes API proxy

The chart’s default values include a Traefik IngressRouteTCP TCP router for your cluster’s Kubernetes API server. This Service proxies HTTP traffic to your cluster over Direct Connect and provides TLS passthrough. To locate the hostname of this Service, run the following command:
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.

Create Ingresses with TLS

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 for this purpose.
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 chart. You can also configure your own TLS certificate solution.
ingress-example.yaml - An example using Traefik with TLS and DNS
For more information on Traefik as a Kubernetes Ingress provider, see the official Traefik documentation.
Last modified on June 12, 2026