Gateway DNS configuration for routes attached to a ingress gateway

This tutorial walks you through an example of how to configure DNS for all routes attached to an ingress gateway.

Prerequisites

• Kubernetes cluster with Kuadrant operator installed. See our Getting Started guide for more information.
• kubectl command line tool.
• AWS/Azure or GCP with DNS capabilities.

Setup environment variables

Set the following environment variables used for convenience in this tutorial:

export KUADRANT_GATEWAY_NS=api-gateway # Namespace for the example Gateway
export KUADRANT_GATEWAY_NAME=external # Name for the example Gateway
export KUADRANT_DEVELOPER_NS=toystore # Namespace for an example toystore app
export KUADRANT_AWS_ACCESS_KEY_ID=xxxx # AWS Key ID with access to manage the DNS Zone ID below
export KUADRANT_AWS_SECRET_ACCESS_KEY=xxxx # AWS Secret Access Key with access to manage the DNS Zone ID below
export KUADRANT_AWS_DNS_PUBLIC_ZONE_ID=xxxx # AWS Route 53 Zone ID for the Gateway
export KUADRANT_ZONE_ROOT_DOMAIN=example.com # Root domain associated with the Zone ID above

Create the namespace the Gateway will be deployed in:

kubectl create ns ${KUADRANT_GATEWAY_NS}


### Create a DNS provider secret 
Create AWS provider secret. You should limit the permissions of this credential to only the zones you want us to access.

```bash
kubectl -n ${KUADRANT_GATEWAY_NS} create secret generic aws-credentials \
  --type=kuadrant.io/aws \
  --from-literal=AWS_ACCESS_KEY_ID=$KUADRANT_AWS_ACCESS_KEY_ID \
  --from-literal=AWS_SECRET_ACCESS_KEY=$KUADRANT_AWS_SECRET_ACCESS_KEY

Create an Ingress Gateway

Create a gateway using your KUADRANT_ZONE_ROOT_DOMAIN as part of a listener hostname:

kubectl apply -f - <<EOF
apiVersion: gateway.networking.k8s.io/v1
kind: Gateway
metadata:
  name: ${KUADRANT_GATEWAY_NAME}
  namespace: ${KUADRANT_GATEWAY_NS}
  labels:
    kuadrant.io/gateway: "true"
spec:
  gatewayClassName: istio
  listeners:

    - name: http
      protocol: HTTP
      port: 80
      allowedRoutes:
        namespaces:
          from: All
      hostname: "api.${KUADRANT_ZONE_ROOT_DOMAIN}"    
EOF

Check the status of the Gateway ensuring the gateway is Accepted and Programmed:

kubectl get gateway ${KUADRANT_GATEWAY_NAME} -n ${KUADRANT_GATEWAY_NS} -o=jsonpath='{.status.conditions[?(@.type=="Accepted")].message}{"\n"}{.status.conditions[?(@.type=="Programmed")].message}{"\n"}'

Enable DNS on the gateway

Create a Kuadrant DNSPolicy to configure DNS:

kubectl apply -f - <<EOF
apiVersion: kuadrant.io/v1
kind: DNSPolicy
metadata:
  name: ${KUADRANT_GATEWAY_NAME}-dns
  namespace: ${KUADRANT_GATEWAY_NS}
spec:
  targetRef:
    name: ${KUADRANT_GATEWAY_NAME}
    group: gateway.networking.k8s.io
    kind: Gateway
  providerRefs:  

    - name: aws-credentials
EOF

Check that the DNSPolicy has been Accepted and Enforced (This mat take a few minutes):

kubectl get dnspolicy ${KUADRANT_GATEWAY_NAME}-dns -n ${KUADRANT_GATEWAY_NS} -o=jsonpath='{.status.conditions[?(@.type=="Accepted")].message}{"\n"}{.status.conditions[?(@.type=="Enforced")].message}'

Deploy the Toystore app

Create the namespace for the Toystore application:

kubectl create ns ${KUADRANT_DEVELOPER_NS}

Deploy the Toystore app to the developer namespace:

kubectl apply -f https://raw.githubusercontent.com/Kuadrant/Kuadrant-operator/main/examples/toystore/toystore.yaml -n ${KUADRANT_DEVELOPER_NS}

Setup Toystore application HTTPRoute

kubectl apply -f - <<EOF
apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: toystore
  namespace: ${KUADRANT_DEVELOPER_NS}
  labels:
    deployment: toystore
    service: toystore
spec:
  parentRefs:

  - name: ${KUADRANT_GATEWAY_NAME}
    namespace: ${KUADRANT_GATEWAY_NS}
  hostnames:
  - "api.${KUADRANT_ZONE_ROOT_DOMAIN}"
  rules:
  - matches:
    - method: GET
      path:
        type: PathPrefix
        value: "/cars"
    backendRefs:
    - name: toystore
      port: 80  
EOF

Verify DNS works by sending requests

Verify DNS using dig you should see your IP address:

dig api.${KUADRANT_ZONE_ROOT_DOMAIN} +short

Verify DNS using curl you should get a status 200:

curl http://api.$KUADRANT_ZONE_ROOT_DOMAIN/cars -i