Idempotency fixes (#1838)

roles/kubernetes/master/tasks/main.yml

@@ -12,10 +12,24 @@
 - include: users-file.yml
   when: kube_basic_auth|default(true)
 
+- name: Compare host kubectl with hyperkube container
+  command: "{{ docker_bin_dir }}/docker run --rm -v {{ bin_dir }}:/systembindir {{ hyperkube_image_repo }}:{{ hyperkube_image_tag }} /usr/bin/cmp /hyperkube /systembindir/kubectl"
+  register: kubectl_task_compare_result
+  until: kubectl_task_compare_result.rc in [0,1,2]
+  retries: 4
+  delay: "{{ retry_stagger | random + 3 }}"
+  changed_when: false
+  failed_when: "kubectl_task_compare_result.rc not in [0,1,2]"
+  tags:
+    - hyperkube
+    - kubectl
+    - upgrade
+
 - name: Copy kubectl from hyperkube container
   command: "{{ docker_bin_dir }}/docker run --rm -v {{ bin_dir }}:/systembindir {{ hyperkube_image_repo }}:{{ hyperkube_image_tag }} /bin/cp /hyperkube /systembindir/kubectl"
-  register: kube_task_result
-  until: kube_task_result.rc == 0
+  when: kubectl_task_compare_result.rc != 0
+  register: kubectl_task_result
+  until: kubectl_task_result.rc == 0
   retries: 4
   delay: "{{ retry_stagger | random + 3 }}"
   changed_when: false
@@ -26,7 +40,7 @@
 
 - name: Install kubectl bash completion
   shell: "{{ bin_dir }}/kubectl completion bash >/etc/bash_completion.d/kubectl.sh"
-  when: ansible_os_family in ["Debian","RedHat"]
+  when: kubectl_task_compare_result.rc != 0 and ansible_os_family in ["Debian","RedHat"]
   tags:
     - kubectl
 

roles/kubernetes/master/tasks/pre-upgrade.yml

@@ -5,6 +5,7 @@
     ETCDCTL_API: 2
   register: old_data_exists
   delegate_to: "{{groups['etcd'][0]}}"
+  changed_when: false
   when: kube_apiserver_storage_backend == "etcd3"
   failed_when: false
 

roles/kubernetes/node/tasks/facts.yml

@@ -2,6 +2,7 @@
 - name: look up docker cgroup driver
   shell: "docker info | grep 'Cgroup Driver' | awk -F': ' '{ print $2; }'"
   register: docker_cgroup_driver_result
+  changed_when: false
 
 - set_fact:
     standalone_kubelet: >-

roles/kubernetes/node/tasks/pre_upgrade.yml

@@ -8,4 +8,5 @@
 - name: "Pre-upgrade | ensure kubelet container is stopped if using host deployment"
   command: docker stop kubelet
   failed_when: false
+  changed_when: false
   when: kubelet_deployment_type == 'host'