Find Ingress IP in Helm Chart

Question

What I have:

I have difficulty setting up an Ingress with Helm Chart on the cloud.

• I have a project with a Front, a Back and a MySQL database.
• I setup two Ingress, one for my BackEnd and one for my FrontEnd , I can access it with an IP given by Google Cloud Platform .

In the FrontEnd and BackEnd charts values.yaml :

...
service:
  type: LoadBalancer
  port: 8000 # 4200 for the FrontEnd
  targetPort: 8000 # 4200 for FrontEnd

ingress:
  enabled: true
  annotations:
    kubernetes.io/ingress.class: "nginx"
    nginx.ingress.kubernetes.io/enable-cors: "true"
    nginx.ingress.kubernetes.io/cors-allow-origin: "*"
    nginx.ingress.kubernetes.io/cors-allow-methods: "PUT, GET, POST, OPTIONS, DELETE"
    nginx.ingress.kubernetes.io/cors-allow-headers: "DNT,X-CustomHeader,X-LANG,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-ConSSH / 51970trol,Content-Type,X-Api-Key,X-Device-Id,Access-Control-Allow-Origin"
  hosts:
    - paths:
        - path: /
          pathType: ImplementationSpecific
...

My Issue:

The FrontEnd needs to talk to the BackEnd throughout the Ingress.
In the FrontEnd values.yaml, I need to have a value:
BACKEND_URL: XXX.XXX.XXX.XXX:8000
But I don't know the URL of the BackEnd Ingress, or at least, until I deploy the back.

• How can I variabilize it, to retrieve the URL ingress of the BackEnd ?
• Or at least, how can I find the ingress IP? (I've tried kubectl get ingress, it doesn't show the address).

Answer 1

You have two options:

1. Don't use the ingress but the service DNS name. This way your traffic doesn't even leave the cluster. If your backend service is called api and deployed in the backend namespace you can reach it internally using api.backend . https://kubernetes.io/docs/concepts/services-networking/service/#dns has details about the mechanism.

2. You reserve the IP on GCP side and pass the IP as a parameter to your helm charts. If you don't, each deletion and recreation of the service will end up on a different IP by GCP. Clients who have a cached DNS response will not be able to use your service until it has expired.

For GCP this snippet from the documentation is correct.

Some cloud providers allow you to specify the loadBalancerIP . In those cases, the load-balancer is created with the user-specified loadBalancerIP . If the loadBalancerIP field is not specified, the loadBalancer is set up with an ephemeral IP address. If you specify a loadBalancerIP but your cloud provider does not support the feature, the loadbalancerIP field that you set is ignored.

So get a permanent IP and pass it as loadBalancerIP to the service.

  service:
    spec:
      type: LoadBalancer
      port: 8000 # 4200 for the FrontEnd
      targetPort: 8000 # 4200 for FrontEnd
      loadBalancerIP: <the Global or Regional IP you got from GCP (depends on the LB)>