website/docs/reference/setup-tools/kubeadm/kubeadm-alpha.md

approvers	title
mikedanese luxas jbeda	kubeadm alpha

kubeadm alpha provides a preview of a set of features made available for gathering feedback from the community. Please try it out and give us feedback! {: .caution}

In v1.8.0, kubeadm introduced the kubeadm alpha phase command with the aim of making kubeadm more modular. This modularity enables you to invoke atomic sub-steps of the bootstrap process; you can let kubeadm do some parts and fill in yourself where you need customizations.

kubeadm alpha phase is consistent with kubeadm init workflow, and behind the scene both use the same code.

• kubeadm alpha phase preflight
• kubeadm alpha phase certs
• kubeadm alpha phase kubeconfig
• kubeadm alpha phase controlplane
• kubeadm alpha phase etcd
• kubeadm alpha phase mark-master
• kubeadm alpha phase bootstrap-token
• kubeadm alpha phase upload-config
• kubeadm alpha phase addon
• kubeadm alpha phase selfhosting

kubeadm alpha phase preflight

You can execute preflight checks both for the master node, like in kubeadm init, or for the worker node like in kubeadm join.

{% capture preflight_master %} {% include_relative generated/kubeadm_alpha_phase_preflight_master.md %} {% endcapture %}

{% capture preflight_node %} {% include_relative generated/kubeadm_alpha_phase_preflight_node.md %} {% endcapture %}

{% assign tab_set_name = "tab-preflight" %} {% assign tab_names = "master,node" | split: ',' | compact %} {% assign tab_contents = site.emptyArray | push: preflight_master | push: preflight_node %}

{% include tabs.md %}

kubeadm alpha phase certs

You can create all required certificates with the all subcommand or selectively create certificates.

{% capture certs_all %} {% include_relative generated/kubeadm_alpha_phase_certs_all.md %} {% endcapture %}

{% capture certs_ca %} {% include_relative generated/kubeadm_alpha_phase_certs_ca.md %} {% endcapture %}

{% capture certs_apiserver %} {% include_relative generated/kubeadm_alpha_phase_certs_apiserver.md %} {% endcapture %}

{% capture certs_apiserver-kubelet-client %} {% include_relative generated/kubeadm_alpha_phase_certs_apiserver-kubelet-client.md %} {% endcapture %}

{% capture certs_sa %} {% include_relative generated/kubeadm_alpha_phase_certs_sa.md %} {% endcapture %}

{% capture certs_front-proxy-ca %} {% include_relative generated/kubeadm_alpha_phase_certs_front-proxy-ca.md %} {% endcapture %}

{% capture certs_front-proxy-client %} {% include_relative generated/kubeadm_alpha_phase_certs_front-proxy-client.md %} {% endcapture %}

{% assign tab_set_name = "tab-certs" %} {% assign tab_names = "all,ca,apiserver,apiserver-kubelet-client,sa,front-proxy-ca,front-proxy-client" | split: ',' | compact %} {% assign tab_contents = site.emptyArray | push: certs_all | push: certs_ca | push: certs_apiserver | push: certs_apiserver-kubelet-client | push: certs_sa | push: certs_front-proxy-ca | push: certs_front-proxy-client %}

{% include tabs.md %}

kubeadm alpha phase kubeconfig

You can create all required kubeconfig files with the all subcommand, or selectively create the files. Additionally, the user subcommand supports the creation of kubeconfig files for additional users.

{% capture kubeconfig_all %} {% include_relative generated/kubeadm_alpha_phase_kubeconfig_all.md %} {% endcapture %}

{% capture kubeconfig_admin %} {% include_relative generated/kubeadm_alpha_phase_kubeconfig_admin.md %} {% endcapture %}

{% capture kubeconfig_kubelet %} {% include_relative generated/kubeadm_alpha_phase_kubeconfig_kubelet.md %} {% endcapture %}

{% capture kubeconfig_controller-manager %} {% include_relative generated/kubeadm_alpha_phase_kubeconfig_controller-manager.md %} {% endcapture %}

{% capture kubeconfig_scheduler %} {% include_relative generated/kubeadm_alpha_phase_kubeconfig_scheduler.md %} {% endcapture %}

{% capture kubeconfig_user %} {% include_relative generated/kubeadm_alpha_phase_kubeconfig_user.md %} {% endcapture %}

{% assign tab_set_name = "tab-kubeconfig" %} {% assign tab_names = "all,admin,kubelet,controller-manager,scheduler,user" | split: ',' | compact %} {% assign tab_contents = site.emptyArray | push: kubeconfig_all | push: kubeconfig_admin | push: kubeconfig_kubelet | push: kubeconfig_controller-manager | push: kubeconfig_scheduler | push: kubeconfig_user %}

{% include tabs.md %}

kubeadm alpha phase controlplane

You can create all required static Pod files for the control plane components with the all subcommand, or selectively create the files.

{% capture controlplane_all %} {% include_relative generated/kubeadm_alpha_phase_controlplane_all.md %} {% endcapture %}

{% capture controlplane_apiserver %} {% include_relative generated/kubeadm_alpha_phase_controlplane_apiserver.md %} {% endcapture %}

{% capture controlplane_controller-manager %} {% include_relative generated/kubeadm_alpha_phase_controlplane_controller-manager.md %} {% endcapture %}

{% capture controlplane_scheduler %} {% include_relative generated/kubeadm_alpha_phase_controlplane_scheduler.md %} {% endcapture %}

{% assign tab_set_name = "tab-controlplane" %} {% assign tab_names = "all,apiserver,controller-manager,scheduler" | split: ',' | compact %} {% assign tab_contents = site.emptyArray | push: controlplane_all | push: controlplane_apiserver | push: controlplane_controller-manager | push: controlplane_scheduler %}

{% include tabs.md %}

kubeadm alpha phase etcd

Use the following command to create a self-hosted, local etcd instance based on a static Pod file.

{% capture etcd-local %} {% include_relative generated/kubeadm_alpha_phase_etcd_local.md %} {% endcapture %}

{% assign tab_set_name = "tab-etcd" %} {% assign tab_names = "etcd local" | split: ',' | compact %} {% assign tab_contents = site.emptyArray | push: etcd-local %}

{% include tabs.md %}

kubeadm alpha phase mark-master

Use the following command to label and taint the node with the node-role.kubernetes.io/master="" key-value pair.

{% capture mark-master %} {% include_relative generated/kubeadm_alpha_phase_mark-master.md %} {% endcapture %}

{% assign tab_set_name = "tab-mark-master" %} {% assign tab_names = "mark-master" | split: ',' | compact %} {% assign tab_contents = site.emptyArray | push: mark-master %}

{% include tabs.md %}

kubeadm alpha phase bootstrap-token

Use the following actions to fully configure bootstrap tokens. You can fully configure bootstrap tokens with the all subcommand, or selectively configure single elements.

{% capture bootstrap-token_all %} {% include_relative generated/kubeadm_alpha_phase_bootstrap-token_all.md %} {% endcapture %}

{% capture bootstrap-token_create %} {% include_relative generated/kubeadm_alpha_phase_bootstrap-token_create.md %} {% endcapture %}

{% capture bootstrap-token_cluster-info %} {% include_relative generated/kubeadm_alpha_phase_bootstrap-token_cluster-info.md %} {% endcapture %}

{% capture bootstrap-token_node_allow-auto-approve %} {% include_relative generated/kubeadm_alpha_phase_bootstrap-token_node_allow-auto-approve.md %} {% endcapture %}

{% capture bootstrap-token_node_allow-post-csrs %} {% include_relative generated/kubeadm_alpha_phase_bootstrap-token_node_allow-post-csrs.md %} {% endcapture %}

{% assign tab_set_name = "tab-bootstrap-token" %} {% assign tab_names = "all,create,cluster-info,node allow-auto-approve,node allow-post-csrs" | split: ',' | compact %} {% assign tab_contents = site.emptyArray | push: bootstrap-token_all | push: bootstrap-token_create | push: bootstrap-token_cluster-info | push: bootstrap-token_node_allow-auto-approve | push: bootstrap-token_node_allow-post-csrs %}

{% include tabs.md %}

kubeadm alpha phase upload-config

You can use this command to upload the kubeadm configuration to your cluster. Alternatively, you can use kubeadm config.

{% capture upload-config %} {% include_relative generated/kubeadm_alpha_phase_upload-config.md %} {% endcapture %}

{% assign tab_set_name = "tab-upload-config" %} {% assign tab_names = "upload-config" | split: ',' | compact %} {% assign tab_contents = site.emptyArray | push: upload-config %}

{% include tabs.md %}

kubeadm alpha phase addon

You can install all the available addons with the all subcommand, or install them selectively.

Please note that if kubeadm is invoked with --feature-gates=CoreDNS=true, CoreDNS is installed instead of kube-dns.

{% capture addon-all %} {% include_relative generated/kubeadm_alpha_phase_addon_all.md %} {% endcapture %}

{% capture addon-kube-proxy %} {% include_relative generated/kubeadm_alpha_phase_addon_kube-proxy.md %} {% endcapture %}

{% capture addon-kube-dns %} {% include_relative generated/kubeadm_alpha_phase_addon_kube-dns.md %} {% endcapture %}

{% assign tab_set_name = "tab-addon" %} {% assign tab_names = "all,kube-proxy,kube-dns" | split: ',' | compact %} {% assign tab_contents = site.emptyArray | push: addon-all | push: addon-kube-proxy | push: addon-kube-dns %}

{% include tabs.md %}

kubeadm alpha phase self-hosting

Caution: Self-hosting is an alpha feature. See kubeadm init documentation for self-hosting limitations. {: .caution}

{% capture self-hosting %} {% include_relative generated/kubeadm_alpha_phase_selfhosting_convert-from-staticpods.md %} {% endcapture %}

{% assign tab_set_name = "tab-self-hosting" %} {% assign tab_names = "self-hosting" | split: ',' | compact %} {% assign tab_contents = site.emptyArray | push: self-hosting %}

{% include tabs.md %}

What's next

• kubeadm init to bootstrap a Kubernetes master node
• kubeadm join to connect a node to the cluster
• kubeadm reset to revert any changes made to this host by kubeadm init or kubeadm join