HTTP/3 support for Google Kubernetes Engine (GKE)

This guide shows how to setup HTTP/3 support for Google Kubernetes Engine (GKE). The instructions provided in this page are a continuation of the HTTP/3 in Emissary documentation.

Configuring an external load balancer for GKE

Currently, GKE only supports adding feature flags to alpha clusters, and doesn’t support the creation of mixed protocol services of type LoadBalancer. To configure an external load balancer for GKE, you need to:

1. Reserve a public static IP address.
2. Create two LoadBalancer services, one for TCP and one for UDP.
3. Assign the public static IP address to the loadBalancerIP field.

An example of the two load balancer services described above looks as follows:

# selectors and labels removed for clarity
apiVersion: v1
kind: Service
metadata:
  name: $productDeploymentName$
  namespace: $productNamespace$
spec:
  type: LoadBalancer
  loadBalancerIP: xx.xx.xx.xx # Enter your public static IP address here.
  ports:
    - name: http
      port: 80
      targetPort: 8080
      protocol: TCP
    - name: https
      port: 443
      targetPort: 8443
      protocol: TCP
  ---
  apiVersion: v1
kind: Service
metadata:
  name: $productDeploymentName$-udp
  namespace: $productNamespace$
spec:
  type: LoadBalancer
  loadBalancerIP: xx.xx.xx.xx # Enter your public static IP address here.
  ports:
    - name: http3
      port: 443  # Default support for HTTP/3 requires you to use 443 for the external client-facing port.
      targetPort: 8443
      protocol: UDP

In the above example, GKE generates two LoadBalancer services, one for UDP and the other for TCP.