deployment: Envoy use Contour dns name for gRPC connection

[stevesloka]

Describe the solution you'd like
Updating #1122, in the split deployment model, Envoy utilizes the built-in service environment variables (https://github.com/heptio/contour/blob/master/deployment/ds-hostnet-split/03-envoy.yaml#L67 && https://github.com/heptio/contour/blob/master/deployment/ds-hostnet-split/03-envoy.yaml#L69).

If the deployment or daemonset is created before the service exists, then these variables won't exist.

We should look to have Envoy use the internal dns name of contour instead of the env variable. Last time I attempted this I ran into Envoy issues resolving that name properly.

Also, if we switch to this model, the port cannot be automatically determined. Users will need to keep those numbers in sync (just noting so we can document properly).

[davecheney]

@stevesloka thanks for looking at this. Do you want to tackle this for 0.13, or punt til 0.14? Could you have a think about the best time to tackle this and label/milestone accordingly. Thanks

[stevesloka]

@davecheney this can be a 0.14.0 issue, it's not a critical block at the moment, but we should address soon so it doesn't affect other users.

[davecheney]

Ok, let’s bump it to 0.14.

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On 1 Jun 2019, at 00:13, Steve Sloka ***@***.***> wrote: @davecheney this can be a 0.14.0 issue, it's not a critical block at the moment, but we should address soon so it doesn't affect other users. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or mute the thread.

[youngnick]

Picking up this one to work on in tandem with #862