Microk8s: switch to CoreDNS as Kubernetes has done.

[ljckennedy]

Kubernetes now uses coreDNS instead of kubeDNS. See: https://kubernetes.io/docs/setup/release/notes/#kubernetes-1-13-release-notes

Minikube has already done this and OKD 4 will do this also. Microk8s should do the same to maintain compatibility and improve flexibility.

Thanks.

[magne]

@ktsakalozos, should this replace the existing dns addon, or be a separate addon? If replacement, what about existing installations?

[ljckennedy]

My view, is it should be the new default. but the old add-on should probably stay for a while but be marked as deprecated. Just my opinion though..

[Xtigyro]

Yes - it should become the new default DNS resolution mechanism - the one from CoreOS.

In the meantime, to do it manually:

microk8s.disable dns
git clone https://github.com/coredns/deployment.git
cd deployment/kubernetes
./deploy.sh | kubectl apply -f -

[richardcase]

I agree it should be the new default

[ktsakalozos]

CoreDNS replaced KubeDNS in the commit:
https://github.com/ubuntu/microk8s/commit/4a1d2a7d17ddbebdad34418a78e981e4ee24680e

microk8s.enable dns will give you coredns.

Should reach stable with the 1.15 release.

[Xtigyro]

@ktsakalozos Thank you!

[ktsakalozos]

All the credit goes to @richardcase for driving this.