Can't change gateway port on service

[jenwirth]

Hi,

I must be missing something, because i am stuck with something that seems simple.

I have the following service (from, just changed the http port to 8080 on the listener)

apiVersion: v1
kind: Service
metadata:
  name: nginx-gateway
  namespace: nginx-gateway
  labels:
    app.kubernetes.io/name: nginx-gateway
    app.kubernetes.io/instance: nginx-gateway
    app.kubernetes.io/version: "1.0.0"
spec:
  type: NodePort
  selector:
    app.kubernetes.io/name: nginx-gateway
    app.kubernetes.io/instance: nginx-gateway
  ports: # Update the following ports to match your Gateway Listener ports
  - name: http
    port: 8080
    protocol: TCP
    targetPort: 80
  - name: https
    port: 443
    protocol: TCP
    targetPort: 443

Then i create a gateway with a listener on port 8080:

apiVersion: gateway.networking.k8s.io/v1
kind: Gateway
metadata:
  name: hello
  namespace: default
spec:
  gatewayClassName: nginx
  listeners:
  - name: http
    port: 8080
    protocol: HTTP

I also have a route, which does not seem relevant, listing for sake of completeness:

apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: hello
  namespace: default
spec:
  parentRefs:
  - name: hello
  hostnames:
  - "hello.example.com"
  rules:
  - matches:
    - path:
        type: PathPrefix
        value: /
    backendRefs:
    - name: hello-app
      port: 3000

Now getting the nodeport of the nginx-gateway:

k -n nginx-gateway get svc
NAME            TYPE       CLUSTER-IP      EXTERNAL-IP   PORT(S)                        AGE
nginx-gateway   NodePort   10.99.245.204   <none>        8080:32516/TCP,443:30640/TCP   36m

And then trying to curl:

curl -k https://node-1:32516 -H "Host: hello.example.com"
curl: (7) Failed to connect to machine-1 port 32516 after 0 ms: Connection refused

If I change the port on the service and gateway listener back to 80, it works.

How can I change the port number as indicated in the comment (and mentioned here: https://docs.nginx.com/nginx-gateway-fabric/installation/expose-nginx-gateway-fabric/)

tx.,

[kate-osborn]

Hi @jenwirth,

The targetPort in your service definition also needs to be changed to 8080. The targetPort is the port on which the service will send requests to. With the current configuration, the service is exposed on port 8080 (mapped to NodePort 32516) but forwards the request to the NGINX Gateway Fabric Pod on port 80.

[jenwirth]

Thanks for your help!

Does that mean the NGINX Gateway Fabric Pod listens to more ports that listed on its pod definition (see below)

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-gateway
  namespace: nginx-gateway
spec:
  …
  template:
    spec:
      - image: ghcr.io/nginxinc/nginx-gateway-fabric/nginx:1.1.0
        name: nginx
        ports:
        - containerPort: 80
          name: http
          protocol: TCP
        - containerPort: 443
          name: https
          protocol: TCP

[kate-osborn]

The NGINX Gateway Fabric will listen on the ports defined in the Gateway resource. So, if you create the following Gateway:

apiVersion: gateway.networking.k8s.io/v1
kind: Gateway
metadata:
  name: hello
  namespace: default
spec:
  gatewayClassName: nginx
  listeners:
  - name: http
    port: 80
    protocol: HTTP
  - name: https
    port: 443
    protocol: HTTPS

NGINX Gateway Fabric will listen on ports 80 and 443. These are the ports defined in the default Service and Pod specs.

If you want NGINX Gateway Fabric to listen on different ports -- say 8080 and 8443 -- you will create the following Gateway instead:

apiVersion: gateway.networking.k8s.io/v1
kind: Gateway
metadata:
  name: hello
  namespace: default
spec:
  gatewayClassName: nginx
  listeners:
  - name: http
    port: 8080
    protocol: HTTP
  - name: https
    port: 8443
    protocol: HTTPS

This will configure NGINX Gateway Fabric to listen on 8080 and 8443. But you also need to update the Service spec so that Kubernetes routes requests to these ports on the NGINX Gateway Fabric Pod. The containerPorts you posted above can also be changed to 8080 and 8443, but this is not required. The containerPort in the Pod spec is optional. A Service will send traffic to the Pod on the TargetPort defined in the Service spec, regardless if there's a matching containerPort defined on the Pod.