From a198e2de6f95b9ee47bab5af60ea1dab1e4c361c Mon Sep 17 00:00:00 2001 From: "Lubomir I. Ivanov" Date: Wed, 24 Mar 2021 01:08:14 +0200 Subject: [PATCH] kubeadm: remove page about self-hosting support The command "kubeadm alpha self-hosting" was removed in 1.21. Remove the page that talks about self-hosting support in kubeadm. --- .../tools/kubeadm/self-hosting.md | 68 ------------------- 1 file changed, 68 deletions(-) delete mode 100644 content/en/docs/setup/production-environment/tools/kubeadm/self-hosting.md diff --git a/content/en/docs/setup/production-environment/tools/kubeadm/self-hosting.md b/content/en/docs/setup/production-environment/tools/kubeadm/self-hosting.md deleted file mode 100644 index d860a88bdd..0000000000 --- a/content/en/docs/setup/production-environment/tools/kubeadm/self-hosting.md +++ /dev/null @@ -1,68 +0,0 @@ ---- -reviewers: -- sig-cluster-lifecycle -title: Configuring your kubernetes cluster to self-host the control plane -content_type: concept -weight: 100 ---- - - - -### Self-hosting the Kubernetes control plane {#self-hosting} - -kubeadm allows you to experimentally create a _self-hosted_ Kubernetes control -plane. This means that key components such as the API server, controller -manager, and scheduler run as [DaemonSet pods](/docs/concepts/workloads/controllers/daemonset/) -configured via the Kubernetes API instead of [static pods](/docs/tasks/configure-pod-container/static-pod/) -configured in the kubelet via static files. - -To create a self-hosted cluster see the -[kubeadm alpha selfhosting pivot](/docs/reference/setup-tools/kubeadm/kubeadm-alpha/#cmd-selfhosting) command. - - - -#### Caveats - -{{< caution >}} -This feature pivots your cluster into an unsupported state, rendering kubeadm unable -to manage you cluster any longer. This includes `kubeadm upgrade`. -{{< /caution >}} - -1. Self-hosting in 1.8 and later has some important limitations. In particular, a - self-hosted cluster _cannot recover from a reboot of the control-plane node_ - without manual intervention. - -1. By default, self-hosted control plane Pods rely on credentials loaded from - [`hostPath`](/docs/concepts/storage/volumes/#hostpath) - volumes. Except for initial creation, these credentials are not managed by - kubeadm. - -1. The self-hosted portion of the control plane does not include etcd, - which still runs as a static Pod. - -#### Process - -The self-hosting bootstrap process is documented in the [kubeadm design -document](https://github.com/kubernetes/kubeadm/blob/master/docs/design/design_v1.9.md#optional-self-hosting). - -In summary, `kubeadm alpha selfhosting` works as follows: - - 1. Waits for this bootstrap static control plane to be running and - healthy. This is identical to the `kubeadm init` process without self-hosting. - - 1. Uses the static control plane Pod manifests to construct a set of - DaemonSet manifests that will run the self-hosted control plane. - It also modifies these manifests where necessary, for example adding new volumes - for secrets. - - 1. Creates DaemonSets in the `kube-system` namespace and waits for the - resulting Pods to be running. - - 1. Once self-hosted Pods are operational, their associated static Pods are deleted - and kubeadm moves on to install the next component. This triggers kubelet to - stop those static Pods. - - 1. When the original static control plane stops, the new self-hosted control - plane is able to bind to listening ports and become active. - -