Enabling kubernetesGateway in traefik

[rotty3000]

Hello everyone, I'd like to experiment with Gateway API in k3d and I'd wondering how I go about enabling the kubernetesGateway provider in traefik.

[rotty3000]

Ok, I've gotten it working. Here's what I got:

Setup K3D with Traefik's Gateway Implementation

Create a K3d cluster without Traefik at first:

k3d cluster create kdex --port 80:80@loadbalancer --port 443:443@loadbalancer --port 8000:8000@loadbalancer --k3s-arg "--disable=traefik@server:0"

Add Traefik helm repository:

helm repo add traefik https://traefik.github.io/charts
helm repo update

Setup a values.yaml file as follows:

# https://github.com/traefik/traefik-helm-chart/blob/master/traefik/values.yaml
deployment:
  podAnnotations:
    prometheus.io/port: "8082"
    prometheus.io/scrape: "true"
gateway:
  listeners:
    web:
      namespacePolicy: All
priorityClassName: system-cluster-critical
providers:
  kubernetesGateway:
    enabled: true
service:
  ipFamilyPolicy: PreferDualStack
tolerations:
- key: CriticalAddonsOnly
  operator: Exists
- effect: NoSchedule
  key: node-role.kubernetes.io/control-plane
  operator: Exists
- effect: NoSchedule
  key: node-role.kubernetes.io/master
  operator: Exists

Install Traefik using those values:

helm upgrade --install --version 32.1.1 --namespace kube-system traefik traefik/traefik -f values.yaml

Apply a sample:

# Deployment
apiVersion: apps/v1
kind: Deployment
metadata:
  name: whoami-deployment
  labels:
    app: whoami
spec:
  replicas: 1
  selector:
    matchLabels:
      app: whoami
  template:
    metadata:
      labels:
        app: whoami
    spec:
      containers:
      - image: docker.io/containous/whoami:v1.5.0
        name: whoami
        ports:
        - containerPort: 80
---
# Service
apiVersion: v1
kind: Service
metadata:
  name: whoami-service
spec:
  ports:
  - name: whoami
    port: 80
    targetPort: 80
  selector:
    app: whoami
---
# HTTPRoute
apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: whoami-httproute
spec:
  parentRefs:
  - name: traefik-gateway
    namespace: kube-system
  hostnames:
  - whoami.docker.localhost
  rules:
  - matches:
    - path:
        type: PathPrefix
        value: /
    backendRefs:
    - name: whoami-service
      port: 80

Test it out:

curl http://whoami.docker.localhost

Hopefully this helps someone else that wants to try it out! And also maybe there's a simpler way.

[rotty3000]

Ok, so I thought that maybe I could reduce this down to using HelmChartConfig against the existing traefik helm AddOns in k3s. However, that doesn't let you change the chart or version. And docker.io/rancher/mirrored-library-traefik doesn't have any of the traefik V3 images mirrored.

[rotty3000]

A slightly more maintainable approach using K3s HelmChart support:

Setup K3D with Traefik's Gateway Implementation

Create a K3d cluster with LoadBalancer:

k3d cluster create kdex --port 80:80@loadbalancer --port 443:443@loadbalancer --port 8000:8000@loadbalancer

Create the following HelmChart resource which installs the Gateway API CRDs:

kubectl apply -f - <<EOF
apiVersion: helm.cattle.io/v1
kind: HelmChart
metadata:
  name: gateway-api-crds
  namespace: kube-system
spec:
  chart: gateway-api
  version: 2024.8.30
  repo: https://charts.appscode.com/stable/
EOF

Create the following HelmChart resource which overrides the Traefik addon updating Traefik and enabling the Gateway API provider:

kubectl apply -f - <<EOF
apiVersion: helm.cattle.io/v1
kind: HelmChart
metadata:
  name: traefik
  namespace: kube-system
spec:
  chart: traefik
  version: 32.1.1
  repo: https://traefik.github.io/charts
  valuesContent: |-
    deployment:
      podAnnotations:
        prometheus.io/port: "8082"
        prometheus.io/scrape: "true"
    gateway:
      listeners:
        web:
          namespacePolicy: All
    priorityClassName: system-cluster-critical
    providers:
      kubernetesGateway:
        enabled: true
    service:
      ipFamilyPolicy: PreferDualStack
    tolerations:
    - key: "CriticalAddonsOnly"
      operator: "Exists"
    - key: "node-role.kubernetes.io/control-plane"
      operator: "Exists"
      effect: "NoSchedule"
    - key: "node-role.kubernetes.io/master"
      operator: "Exists"
      effect: "NoSchedule"
EOF

Apply a sample:

kubectl apply -f - <<EOF
# Deployment
apiVersion: apps/v1
kind: Deployment
metadata:
  name: whoami-deployment
  labels:
    app: whoami
spec:
  replicas: 1
  selector:
    matchLabels:
      app: whoami
  template:
    metadata:
      labels:
        app: whoami
    spec:
      containers:
      - image: docker.io/containous/whoami:v1.5.0
        name: whoami
        ports:
        - containerPort: 80
---
# Service
apiVersion: v1
kind: Service
metadata:
  name: whoami-service
spec:
  ports:
  - name: whoami
    port: 80
    targetPort: 80
  selector:
    app: whoami
---
# HTTPRoute
apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: whoami-httproute
spec:
  parentRefs:
  - name: traefik-gateway
    namespace: kube-system
  hostnames:
  - whoami.docker.localhost
  rules:
  - matches:
    - path:
        type: PathPrefix
        value: /
    backendRefs:
    - name: whoami-service
      port: 80
EOF

Test it out:

curl http://whoami.docker.localhost

References

• Gateway API - Specification
• Traefik Gateway API
• Traefik Helm Values
• Traefik manifest in K3s
• K3s Helm AddOns (HelmChart)