AWS route53 external dns point only one A records to the (E)LB of the (nginx) ingress controller - amazon-web-services

Question

I have created two ingresses, one for Grafana and one for my App. When the external dns write them into the route53 hosted zone as a A record, only one of them (the Myapp dns) get the (E)LB alias (dns), though the second A record get the internal IP as an ip address in the route53 A record.
the big question:
is there a way to set them all to the same alias/or at list to the same elb?
why it doesn't success doing so by default?
using:
terraform:
helm_release:
nginx-controller-bitnami
external-dns-bitnami
prometheus community
grafana-ingress:
apiVersion: v1
items:
- apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
annotations:
kubernetes.io/ingress.class: nginx
meta.helm.sh/release-name: kube-prometheus-stack
meta.helm.sh/release-namespace: prometheus
generation: 1
labels:
app.kubernetes.io/instance: kube-prometheus-stack
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/name: grafana
app.kubernetes.io/version: 8.3.3
helm.sh/chart: grafana-6.20.5
name: kube-prometheus-stack-grafana
namespace: prometheus
resourceVersion: "2419"
spec:
rules:
- host: grafana.dns.io
http:
paths:
- backend:
service:
name: kube-prometheus-stack-grafana
port:
number: 80
path: /
pathType: Prefix
status:
loadBalancer:
ingress:
- ip: 10.0.1.19
kind: List
metadata:
resourceVersion: ""
selfLink: ""
my-app-ingress
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: app-ingress
annotations:
ingress.kubernetes.io/ssl-redirect: /
nginx.ingress.kubernetes.io/rewrite-target: /$1
kubernetes.io/ingress.class: nginx
spec:
rules:
- host: "some.website.io"
http:
paths:
- pathType: Prefix
path: "/"
backend:
service:
name: "{{ .Release.Name }}-app"
port:
number: 80
status:
loadBalancer:
ingress:
- ip: 10.0.1.19
nginx-controller-service
kind: Service
metadata:
annotations:
external-dns.alpha.kubernetes.io/hostname: website.my-app.io, some.grafana.io
meta.helm.sh/release-name: nginx-ingress-controller
meta.helm.sh/release-namespace: default
finalizers:
- service.kubernetes.io/load-balancer-cleanup
labels:
app.kubernetes.io/component: controller
app.kubernetes.io/instance: nginx-ingress-controller
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/name: nginx-ingress-controller
helm.sh/chart: nginx-ingress-controller-9.1.4
name: nginx-ingress-controller
namespace: default
resourceVersion: "997"
spec:
clusterIP: 172.30.0.140
clusterIPs:
- 172.30.0.140
externalTrafficPolicy: Cluster
ipFamilies:
- IPv4
ipFamilyPolicy: SingleStack
ports:
- name: http
nodePort: 30337
port: 80
protocol: TCP
targetPort: http
- name: https
nodePort: 31512
port: 443
protocol: TCP
targetPort: https
selector:
app.kubernetes.io/component: controller
app.kubernetes.io/instance: nginx-ingress-controller
app.kubernetes.io/name: nginx-ingress-controller
sessionAffinity: None
type: LoadBalancer
status:
loadBalancer:
ingress:
- hostname: someElbDns.eu-west-1.elb.amazonaws.com

Answer 1

Since your ingress controller service is of type LoadBalancer, creating this service will provision an NLB for you which will have your nginx controller pods as target groups.
A request will pass from the NLB to the ingress pods and then to grafana/your app subsequently.
I would try to use the same host (website.io) and the same nginx ingress class so both ingresses get assigned the same NLB address:
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
namespace: default
name: grafana-ingress
annotations:
nginx.ingress.kubernetes.io/force-ssl-redirect: "false"
kubernetes.io/ingress.class: "nginx"
spec:
tls:
- hosts:
- grafana.website.io
secretName: tls-secret-website-io
rules:
- host: website.io
- http:
paths:
- path: /
backend:
serviceName: grafana-service
servicePort: 80
---
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
namespace: default
name: awebsite-ingress
annotations:
nginx.ingress.kubernetes.io/force-ssl-redirect: "false"
kubernetes.io/ingress.class: "nginx"
spec:
tls:
- hosts:
- subdomain.website.io
secretName: tls-secret-website-io
rules:
- host: website.io
- http:
paths:
- path: /(/|$)(.*)
backend:
serviceName: website-service
servicePort: 80
kind: Service
apiVersion: v1
metadata:
name: nginx-controller
namespace: ingress-nginx
labels:
app.kubernetes.io/name: nginx-controller
app.kubernetes.io/part-of: nginx-controller
annotations:
# by default the type is elb (classic load balancer).
service.beta.kubernetes.io/aws-load-balancer-type: nlb
spec:
# this setting is to make sure the source IP address is preserved.
externalTrafficPolicy: Local
type: LoadBalancer
selector:
app.kubernetes.io/name: nginx-controller
app.kubernetes.io/part-of: nginx-controller
ports:
- name: http
port: 80
targetPort: http
- name: https
port: 443
targetPort: https
Last step is to create a CNAME entry in Rote53 from your domain to the loadbalancer DNS.