Fetch node labels only when enable-topology-aware-routing is true

[gramulka]

What happened:

We're not using enable-topology-aware-routing flag, and cluster access is disabled for us, and on startup nginx gives us the following warning: "W1121 08:47:25.273958 7 main.go:125] Unable to get NODE information: nodes "....internal" is forbidden: User "..." cannot get resource "nodes" in API group "" at the cluster scope"

What you expected to happen:

As enable-topology-aware-routing is disabled by default, we're expecting that nginx wouldn't try to fetch node labels.

NGINX Ingress controller version (exec into the pod and run nginx-ingress-controller --version.):

nginx controller version: 1.8.4

Kubernetes version (use kubectl version): 1.26

Environment:

• Cloud provider or hardware configuration:

• OS (e.g. from /etc/os-release):

• Kernel (e.g. uname -a):

• Install tools:

  • Please mention how/where was the cluster created like kubeadm/kops/minikube/kind etc.

• Basic cluster related info:

  • kubectl version
  • kubectl get nodes -o wide

• How was the ingress-nginx-controller installed:

  • If helm was used then please show output of helm ls -A | grep -i ingress
  • If helm was used then please show output of helm -n <ingresscontrollernamepspace> get values <helmreleasename>
  • If helm was not used, then copy/paste the complete precise command used to install the controller, along with the flags and options used
  • if you have more than one instance of the ingress-nginx-controller installed in the same cluster, please provide details for all the instances

• Current State of the controller:

  • kubectl describe ingressclasses
  • kubectl -n <ingresscontrollernamespace> get all -A -o wide
  • kubectl -n <ingresscontrollernamespace> describe po <ingresscontrollerpodname>
  • kubectl -n <ingresscontrollernamespace> describe svc <ingresscontrollerservicename>

• Current state of ingress object, if applicable:

  • kubectl -n <appnnamespace> get all,ing -o wide
  • kubectl -n <appnamespace> describe ing <ingressname>
  • If applicable, then, your complete and exact curl/grpcurl command (redacted if required) and the reponse to the curl/grpcurl command with the -v flag

• Others:

  • Any other related information like ;
  • copy/paste of the snippet (if applicable)
  • kubectl describe ... of any custom configmap(s) created and in use
  • Any other related information that may help

How to reproduce this issue:

Anything else we need to know:

[k8s-ci-robot]

This issue is currently awaiting triage.

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