Make Eirini apps work with our DNS

[f0rmiga]

Describe the bug

Since Eirini apps cannot resolve the DNS records from the kubecf coreDNS instance, credhub.servie.cf.internal becomes unreachable.

To Reproduce

Deploy kubecf with Eirini and check that credhub CATS suite doesn't pass.

Expected behavior

Eirini apps should be able to resolve the kubecf DNS entries. It may be possible with an EiriniX mutator.

Environment

All versions.

[f0rmiga]

Blocked by cloudfoundry-incubator/eirinix#18 and cloudfoundry-incubator/eirini-loggregator-bridge#4.

[f0rmiga]

I currently got an Eirinix working for mutating the apps, pointing them to the kubecf custom DNS instances. credhub tests fail due to, apparently, trying to set an environment variable at runtime. Since k8s doesn't support this behaviour without restarting, I'm in the process of finding out if the failing credhub tests are relevant in the Eirini world.

[mook-as]

For some context: there's some experimental code in https://github.com/SUSE/eirini-dns-aliases/tree/f0rmiga/initial-impl (the meat of which is https://github.com/SUSE/eirini-dns-aliases/blob/f0rmiga/initial-impl/pkg/extension/extension.go ).

[mook-as]

This is going to involved cloudfoundry-incubator/eirinix#40 — eirinix has really old quarks dependencies. (It still refers to cf-operator in the import, which makes it not build.)

[jandubois]

(It still refers to cf-operator in the import, which makes it not build.)

If you need a quick fix for building it, here is what I did in https://github.com/SUSE/eirini-persi/blob/master/go.mod#L25

[mook-as]

PR posted in SUSE/eirini-dns-aliases#1

Required changes to test:

• Add chart to deploy/helm/kubecf/requirements.yaml; something like

- name: eirini-dns-aliases
  repository: https://mook-as.github.io/eirini-dns-aliases/
  version: v0.0.0-dev+10-gcc1efd5
  condition: features.eirini.enabled

• Run dev/helm/update_subcharts.sh
• Add configuration to values.yaml, or one of the newfangled config files:

eirini-dns-aliases:
  deployment:
    eirini_namespace: eirini

Test by hijacking into one of the eirini-deployed apps (eirini-ssh seems busted again for me), and run curl -k https://credhub:8844/ — you should get a JSON response back.

[andreas-kupries]

Blocked on its PR, which is blocked in turn on #1259

@mook-as I notice that #1259 is merged. Would this unblock the linked #1275 ?

[mook-as]

@andreas-kupries I believe #1275 is currently waiting on SUSE/eirini-dns-aliases#1

[andreas-kupries]

Ok then. Marking it as blocked was correct.