diff --git a/content/en/docs/tasks/administer-cluster/coredns.md b/content/en/docs/tasks/administer-cluster/coredns.md index 00cbe26aa685e..7055b21f6b302 100644 --- a/content/en/docs/tasks/administer-cluster/coredns.md +++ b/content/en/docs/tasks/administer-cluster/coredns.md @@ -29,7 +29,9 @@ deployment, or by using tools like kubeadm that will deploy and upgrade the clus For manual deployment or replacement of kube-dns, see the documentation at the [CoreDNS GitHub project.](https://github.com/coredns/deployment/tree/master/kubernetes) -## Upgrading an existing cluster with kubeadm +## Migrating to CoreDNS + +### Upgrading an existing cluster with kubeadm In Kubernetes version 1.10 and later, you can also move to CoreDNS when you use `kubeadm` to upgrade a cluster that is using `kube-dns`. In this case, `kubeadm` will generate the CoreDNS configuration @@ -53,7 +55,8 @@ customizations after the new ConfigMap is up and running. If you are running CoreDNS in Kubernetes version 1.11 and later, during upgrade, your existing Corefile will be retained. -## Installing kube-dns instead of CoreDNS with kubeadm + +### Installing kube-dns instead of CoreDNS with kubeadm {{< note >}} In Kubernetes 1.11, CoreDNS has graduated to General Availability (GA) @@ -69,6 +72,14 @@ kubeadm init --feature-gates=CoreDNS=false For versions 1.13 and later, follow the guide outlined [here](/docs/reference/setup-tools/kubeadm/kubeadm-init-phase#cmd-phase-addon). +## Upgrading CoreDNS + +CoreDNS is available in Kubernetes since v1.9. +You can check the version of CoreDNS shipped with Kubernetes and the changes made to CoreDNS [here](https://github.com/coredns/deployment/blob/master/kubernetes/CoreDNS-k8s_version.md). + +CoreDNS can be upgraded manually in case you want to only upgrade CoreDNS or use your own custom image. +There is a helpful [guideline and walkthrough](https://github.com/coredns/deployment/blob/master/kubernetes/Upgrading_CoreDNS.md) available to ensure a smooth upgrade. + ## Tuning CoreDNS When resource utilisation is a concern, it may be useful to tune the configuration of CoreDNS. For more details, check out the