Ingress-nginx: Feature request: [nginx] server aliases

[egeland]

There are situations where you may need to have a server alias separate from the ingress host: entry - an annotation to add aliases would be handy.

Suggested implementation

I'd imagine something like:

...
  kind: Ingress
  metadata:
    annotations:
      kubernetes.io/ingress.class: nginx
      kubernetes.io/ingress.serverAlias: anotherhostname.example.com
...
    spec:
    rules:
    - host: mainhost.example.com
...

The implementation would just be to insert the contents of the serverAlias immediately after (space-separated) the $server.Hostname in the config template.

Use case

To expand on the use case - when the dns-controller is set to watch ingresses, all host: entries become DNS entries. If you want the ingress to listen for a host name, but control the DNS from elsewhere for just one of the entries (putting a CDN in front, for example), having the ability to add an alias via an annotation will be useful.

[diazjf]

https://github.com/kubernetes/ingress/pull/1123

@egeland @aledbf Let me know what you think.

[egeland]

As far as I understand it, the commit looks like a perfect fit to what I'm looking for! :+1:

[benbonnet]

Hello, i haven't found many examples, at least not for this one; just wondering if it was possible to have multiple aliases

Something like : kubernetes.io/ingress.serverAlias: "site-b.com,site-c.com,site-d.com", or by passing a yaml array to the annotation

[antoineco]

Yes, just separate them with spaces instead of commas.