ELB Cname alias not picked up

[alexnederlof]

Not sure if this Is a bug or just not implemented.

Using version 0.5, and amazon Route 53, when I create an nginx-ingress (using helm stable/nginx-ingress), it creates a service that gets the external IP <some-hash>.elb.eu-west-1.amazonaws.com.

NAME                                          TYPE           CLUSTER-IP       EXTERNAL-IP                                                                     PORT(S)                      AGE   SELECTOR
default-nginx-nginx-ingress-controller        LoadBalancer   10.x.x.x   <some-hash>.elb.eu-west-1.amazonaws.com   80:30447/TCP,443:31025/TCP   26m   app=nginx-ingress,component=controller,release=defa

When I configured the ingress like so:

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  annotations:
    kubernetes.io/ingress.class: nginx
    external-dns.alpha.kubernetes.io/alias: "true"
  name: hello-a-ingress
  namespace: default
spec:
  rules:
    - host: hello.my.domain

I expected external-dns, to pick up the CNAME, and put that as an alias. However, it sets some IP address in Route 53 (which does not work, because that IP address accepts no traffic).

To fix it, I need to explicitly wait for the ingress to come online, manually grab the CNAME, and then apply the annotation external-dns.alpha.kubernetes.io/target: <some-hash>.elb.eu-west-1.amazonaws.com.

Is this intended behaviour? If so, is it possible to automate it?

[linki]

Your expectation is correct but you're locking at the wrong place. The used ALIAS target will be in your hello-a-ingress Ingress object (not in default-nginx-nginx-ingress-controller). There, under the .status section you'll probably see the IP you're refering to which is set by nginx ingress controller.

Please make sure you're using the --publish-service flag on your ingress controller and point it to default-nginx-nginx-ingress-controller, see https://github.com/kubernetes-incubator/external-dns/blob/master/docs/tutorials/nginx-ingress.md#with-a-separate-tcp-load-balancer.

[alexnederlof]

Thanks! I'll try that!

[frankgu968]

@alexnederlof did it work for you?

@linki I tried adding the publish-service flag and it didn't work... It's still fetching the IP addresses of the ELB.

[alexnederlof]

Yes, worked like a charm!