kube-dns sidecar container doesn't expose metrics

[kovszilard]

Is this a request for help?: NO

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Is this an ISSUE or FEATURE REQUEST? (choose one): ISSUE

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What version of acs-engine?: ALL

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Orchestrator and version (e.g. Kubernetes, DC/OS, Swarm) Kubernetes

What happened: Running a kubernetes cluster

What you expected to happen: kube-dns should expose metrics in Prometheus format as in other cloud providers

How to reproduce it (as minimally and precisely as possible): Install cluster using acs engine

Anything else we need to know: If you check the original kube-dns addon https://github.com/kubernetes/kubernetes/blob/master/cluster/addons/dns/kube-dns/kube-dns.yaml.base you can see that the sidecar container exposes a metrics endpoint on port 10054. This metrics are very useful and monitoring tools like prometheus-operator try to scrape it by default.

Related issues:
Azure/AKS#345

[StianOvrevage]

We're also hitting this now. It appears that kube-dns on AKS/ACS does not include the sidecar container.

Also of possible interest: https://github.com/kubernetes/dns/blob/master/docs/sidecar/README.md

[kovszilard]

#3373 fixed the issue