apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: web-ing
  namespace: prod
spec:
  ingressClassName: nginx
  rules:
    - host: app.example.com
      http:
        paths:
          - path: /
            pathType: Prefix
            backend:
              service:
                name: web
                port:
                  number: 80

kubectl get ingress -n prod
kubectl describe ingress web-ing -n prod
kubectl -n ingress-nginx logs deploy/ingress-nginx-controller --tail=50
curl -H 'Host: app.example.com' http://<入口IP>/