Enable kubeadm etcd mode (#4818)

* Enable kubeadm etcd mode

Uses cert commands from kubeadm experimental control plane to
enable non-master nodes to obtain etcd certs.

Related story: PROD-29434

Change-Id: Idafa1d223e5c6ceadf819b6f9c06adf4c4f74178

* Add validation checks and exclude calico kdd mode

Change-Id: Ic234f5e71261d33191376e70d438f9f6d35f358c

* Move etcd mode test to ubuntu flannel HA job

Change-Id: I9af6fd80a1bbb1692ab10d6da095eb368f6bc732

* rename etcd_mode to etcd_kubeadm_enabled

Change-Id: Ib196d6c8a52f48cae370b026f7687ff9ca69c172

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

@@ -0,0 +1,18 @@
+---
+- name: Calculate etcd cert serial
+  command: "openssl x509 -in {{ kube_cert_dir }}/apiserver-etcd-client.crt -noout -serial"
+  register: "etcd_client_cert_serial_result"
+  changed_when: false
+  tags:
+    - network
+
+- name: Set etcd_client_cert_serial
+  set_fact:
+    etcd_client_cert_serial: "{{ etcd_client_cert_serial_result.stdout.split('=')[1] }}"
+  tags:
+    - network
+
+- name: Ensure etcdctl binary is installed
+  include_tasks: "{{ role_path }}/../../etcd/tasks/install_host.yml"
+  vars:
+    etcd_cluster_setup: true

roles/kubernetes/master/tasks/kubeadm-secondary-experimental.yml

@@ -43,6 +43,10 @@
     kubeadm_certificate_key: "{{ hostvars[groups['kube-master'][0]]['kubeadm_upload_cert'].stdout_lines[-1] | trim }}"
   when: kubeadm_certificate_key is undefined
 
+- name: check already run
+  debug:
+    msg: "{{ kubeadm_already_run.stat.exists }}"
+
 - name: Joining control plane node to the cluster.
   command: >-
     {{ bin_dir }}/kubeadm join
@@ -52,9 +56,11 @@
     --certificate-key={{ kubeadm_certificate_key }}
     {% endif %}
   register: kubeadm_join_control_plane
+  retries: 3
+  until: kubeadm_join_control_plane is succeeded
   when:
     - inventory_hostname != groups['kube-master']|first
-    - not kubeadm_already_run.stat.exists
+    - kubeadm_already_run is not defined or not kubeadm_already_run.stat.exists
   environment:
     PATH: "{{ bin_dir }}:{{ ansible_env.PATH }}"
 

roles/kubernetes/master/tasks/main.yml

@@ -75,3 +75,7 @@
 
 - name: Include kubeadm setup
   import_tasks: kubeadm-setup.yml
+
+- name: Include kubeadm etcd extra tasks
+  include_tasks: kubeadm-etcd.yml
+  when: etcd_kubeadm_enabled