Use "kubeadm join" to join masters to control plane

inventory/sample/group_vars/k8s-cluster/k8s-cluster.yml

@@ -225,8 +225,6 @@ kata_containers_enabled: false
 kubelet_deployment_type: host
 helm_deployment_type: host
 
-# Enable kubeadm experimental control plane
-kubeadm_control_plane: false
 kubeadm_certificate_key: "{{ lookup('password', credentials_dir + '/kubeadm_certificate_key.creds length=64 chars=hexdigits') | lower }}"
 
 # K8s image pull policy (imagePullPolicy)

roles/kubernetes/kubeadm/tasks/main.yml

@@ -176,7 +176,6 @@
   include_tasks: kubeadm_etcd_node.yml
   when:
     - etcd_kubeadm_enabled
-    - kubeadm_control_plane
     - inventory_hostname not in groups['kube-master']
     - kube_network_plugin in ["calico", "flannel", "canal", "cilium"] or cilium_deploy_additionally | default(false) | bool
     - kube_network_plugin != "calico" or calico_datastore == "etcd"

roles/kubernetes/master/defaults/main/main.yml

@@ -2,9 +2,6 @@
 # disable upgrade cluster
 upgrade_cluster_setup: false
 
-# Enable kubeadm experimental control plane
-kubeadm_control_plane: false
-
 # Experimental kubeadm etcd deployment mode. Available only for new deployment
 etcd_kubeadm_enabled: false
 

roles/kubernetes/master/tasks/kubeadm-setup.yml

@@ -199,13 +199,8 @@
   tags:
     - kubeadm_token
 
-- name: kubeadm | Initialize other masters (experimental control plane)
-  include_tasks: kubeadm-secondary-experimental.yml
-  when: kubeadm_control_plane
-
-- name: kubeadm | Initialize other masters (legacy not control plane)
-  include_tasks: kubeadm-secondary-legacy.yml
-  when: not kubeadm_control_plane
+- name: kubeadm | Join other masters
+  include_tasks: kubeadm-secondary.yml
 
 - name: kubeadm | upgrade kubernetes cluster
   include_tasks: kubeadm-upgrade.yml

roles/kubernetes/preinstall/tasks/0020-verify-settings.yml

@@ -258,12 +258,6 @@
   when: resolvconf_mode is defined
   run_once: true
 
-- name: Stop if kubeadm etcd mode is enabled but experimental control plane is not
-  assert:
-    that: kubeadm_control_plane
-    msg: "kubeadm etcd mode requires experimental control plane"
-  when: etcd_kubeadm_enabled
-
 - name: Stop if etcd deployment type is not host or docker
   assert:
     that: etcd_deployment_type in ['host', 'docker']

roles/kubespray-defaults/defaults/main.yaml

@@ -408,9 +408,6 @@ kubelet_protect_kernel_defaults: true
 ## the k8s cluster.
 kube_feature_gates: []
 
-# Enable kubeadm experimental control plane
-kubeadm_control_plane: false
-
 # Local volume provisioner storage classes
 # Levarages Ansibles string to Python datatype casting. Otherwise the dict_key isn't substituted
 # see https://github.com/ansible/ansible/issues/17324

tests/files/packet_centos7-flannel-containerd-addons-ha.yml

@@ -4,7 +4,6 @@ cloud_image: centos-7
 mode: ha
 
 # Kubespray settings
-kubeadm_control_plane: true
 kubeadm_certificate_key: 3998c58db6497dd17d909394e62d515368c06ec617710d02edea31c06d741085
 kube_proxy_mode: iptables
 kube_network_plugin: flannel

tests/files/packet_ubuntu16-flannel-ha.yml

@@ -6,7 +6,6 @@ mode: ha
 # Kubespray settings
 kube_network_plugin: flannel
 etcd_kubeadm_enabled: true
-kubeadm_control_plane: true
 kubeadm_certificate_key: 3998c58db6497dd17d909394e62d515368c06ec617710d02edea31c06d741085
 skip_non_kubeadm_warning: true
 deploy_netchecker: true

tests/files/packet_ubuntu18-flannel-containerd-ha-once.yml

@@ -5,7 +5,6 @@ mode: ha
 vm_memory: 1600Mi
 
 # Kubespray settings
-kubeadm_control_plane: true
 kubeadm_certificate_key: 3998c58db6497dd17d909394e62d515368c06ec617710d02edea31c06d741085
 kube_proxy_mode: iptables
 kube_network_plugin: flannel

tests/files/packet_ubuntu18-flannel-containerd-ha.yml

@@ -5,7 +5,6 @@ mode: ha
 vm_memory: 1600Mi
 
 # Kubespray settings
-kubeadm_control_plane: true
 kubeadm_certificate_key: 3998c58db6497dd17d909394e62d515368c06ec617710d02edea31c06d741085
 kube_proxy_mode: iptables
 kube_network_plugin: flannel