I have a development cluster on AWS deployed with Kops (cluster with 3 worker nodes and 3 master nodes on the eu-central zone) and I'm trying to set-up an Ingress to expose my app to the external world.

I followed this documentation:

• https://github.com/kubernetes/kops/tree/master/addons/kube-ingress-aws-controller
• https://github.com/zalando-incubator/kube-ingress-aws-controller#trying-it-out

Basically, I deployed skipper Ingress, kube-ingress-aws-controller and external DNS to my cluster and everything was working.
Bellow, I have the scripts of the deployments above mentioned.

Scripts of k8s:

Skipper

apiVersion: extensions/v1beta1
kind: DaemonSet
metadata:
  name: skipper-ingress
  namespace: kube-system
  labels:
    component: ingress
spec:
  selector:
    matchLabels:
      component: ingress
  updateStrategy:
    type: RollingUpdate
  template:
    metadata:
      name: skipper-ingress
      labels:
        component: ingress
        application: skipper
    spec:
      hostNetwork: true
      serviceAccountName: skipper-ingress
      containers:
      - name: skipper-ingress
        image: registry.opensource.zalan.do/pathfinder/skipper:v0.11.17
        ports:
        - name: ingress-port
          containerPort: 9999
          hostPort: 9999
        - name: metrics-port
          containerPort: 9911
        args:
          - "skipper"
          - "-kubernetes"
          - "-kubernetes-in-cluster"
          - "-address=:9999"
          - "-proxy-preserve-host"
          - "-serve-host-metrics"
          - "-enable-ratelimits"
          - "-experimental-upgrade"
          - "-metrics-exp-decay-sample"
          - "-lb-healthcheck-interval=3s"
          - "-metrics-flavour=codahale,prometheus"
          - "-enable-connection-metrics"
        resources:
          requests:
            cpu: 200m
            memory: 200Mi
        readinessProbe:
          httpGet:
            path: /kube-system/healthz
            port: 9999
          initialDelaySeconds: 5
          timeoutSeconds: 5

And regarding skipper RBAC:

apiVersion: v1
kind: ServiceAccount
metadata:
  name: skipper-ingress
  namespace: kube-system

---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRole
metadata:
  name: skipper-ingress
rules:
- apiGroups: ["extensions"]
  resources: ["ingresses", ]
  verbs: ["get", "list"]
- apiGroups: [""]
  resources: ["namespaces", "services", "endpoints", "pods"]
  verbs: ["get", "list"]

---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
  name: skipper-ingress
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: skipper-ingress
subjects:
- kind: ServiceAccount
  name: skipper-ingress
  namespace: kube-system

kube-ingress-aws-controller

apiVersion: apps/v1
kind: Deployment
metadata:
  name: kube-ingress-aws-controller
  annotations:
    kubernetes.io/ingress.class: "skipper"
  namespace: kube-system
  labels:
    application: kube-ingress-aws-controller
    component: ingress
spec:
  replicas: 1
  selector:
    matchLabels:
      application: kube-ingress-aws-controller
      component: ingress
  template:
    metadata:
      labels:
        application: kube-ingress-aws-controller
        component: ingress
    spec:
      serviceAccountName: kube-ingress-aws
      containers:
      - name: controller
        image: registry.opensource.zalan.do/teapot/kube-ingress-aws-controller:latest
        env:
        - name: AWS_REGION
          value: eu-central-1
        args:
          - "--redirect-http-to-https"

And regarding kube-ingress RBAC:

apiVersion: v1
kind: ServiceAccount
metadata:
  name: kube-ingress-aws
  namespace: kube-system

---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: ingress-controller
rules:
- apiGroups:
  - extensions
  resources:
  - ingresses
  verbs:
  - get
  - list
  - watch
- apiGroups:
  - extensions
  resources:
  - ingresses/status
  verbs:
  - patch
  - update
- apiGroups:
  - ""
  resources:
  - configmaps
  verbs:
  - get

---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: ingress-controller
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: ingress-controller
subjects:
- kind: ServiceAccount
  name: default
  namespace: kube-system
- kind: ServiceAccount
  name: default
  namespace: default
- kind: ServiceAccount
  name: kube-ingress-aws
  namespace: kube-system

External DNS

apiVersion: apps/v1
kind: Deployment
metadata:
  name: external-dns
  namespace: kube-system
spec:
  strategy:
    type: Recreate
  selector:
    matchLabels:
      app: external-dns
  template:
    metadata:
      labels:
        app: external-dns
    spec:
      serviceAccountName: external-dns
      containers:
      - name: external-dns
        image: registry.opensource.zalan.do/teapot/external-dns:latest
        args:
        - --source=service
        - --source=ingress
        - --domain-filter=alchemyone.eu # will make ExternalDNS see only the hosted zones matching provided domain, omit to process all available hosted zones
        - --provider=aws
        - --policy=upsert-only # would prevent ExternalDNS from deleting any records, omit to enable full synchronization
        - --aws-zone-type=public # only look at public hosted zones (valid values are public, private or no value for both)
        - --registry=txt
        - --txt-owner-id=my-hostedzone-identifier
      securityContext:
        fsGroup: 65534 # For ExternalDNS to be able to read Kubernetes and AWS token files

And regarding the external DNS RBAC:

apiVersion: v1
kind: ServiceAccount
metadata:
  name: external-dns
  namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRole
metadata:
  name: external-dns
rules:
- apiGroups: [""]
  resources: ["services"]
  verbs: ["get","watch","list"]
- apiGroups: [""]
  resources: ["pods"]
  verbs: ["get","watch","list"]
- apiGroups: ["extensions"]
  resources: ["ingresses"]
  verbs: ["get","watch","list"]
- apiGroups: [""]
  resources: ["nodes"]
  verbs: ["list","watch"]
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
  name: external-dns-viewer
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: external-dns
subjects:
- kind: ServiceAccount
  name: external-dns
  namespace: kube-system

After that I verified that everything was working so I deployed the frontend of my app:

Frontend script:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: frontend
  labels:
    app: frontend
    env: prod
spec:
  replicas: 1
  selector:
    matchLabels:
      app: frontend
  template:
    metadata:
      labels:
        app: frontend
    spec:
      containers:
        - name: frontend
          image: my-react-frontend:latest
          imagePullPolicy: Always
          ports:
            - containerPort: 8080
          readinessProbe:
            httpGet:
              path: /
              port: 8080
            initialDelaySeconds: 30
            periodSeconds: 60
            timeoutSeconds: 5
            successThreshold: 2
          livenessProbe:
            httpGet:
              path: /
              port: 8080
            initialDelaySeconds: 90
            periodSeconds: 60
            timeoutSeconds: 5
            failureThreshold: 2
      hostname: frontend
      imagePullSecrets:
        - name: regcred
---
apiVersion: v1
kind: Service
metadata:
  name: frontend
  labels:
    app: frontend
spec:
  type: ClusterIP
  ports:
    - port: 8080
      name: "frontend-service"
  selector:
    app: frontend

Finally, I deployed the Ingress RESOURCE:

Ingress Resource

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: "test-cluster-ingress"
  annotations:
    kubernetes.io/ingress.class: "skipper"
  labels:
    app: foo-app
spec:
  rules:
  - host: my.example.com
    http:
      paths:
      - backend:
          serviceName: frontend
          servicePort: 8080

As predicted, the record set of "my.example.com" was created on my ROUTE 53 of AWS as an ALIAS of my ALB. However, when I try to go to the host (my.example.com), my frontend is not displayed and a message of "503 Service Temporarily Unavailable" is shown....

Can you tell me what am I doing wrong? Thanks in advance for the help!