Tolerate failed coredns svc errors on kubeadm init/upgrade

Also deletes kube-dns svc in kube-system namespace which is unused

Change-Id: I61798a258efbc3f6ee72cd57f68a776db063d417

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

@@ -60,6 +60,10 @@
   register: kubeadm_join_control_plane
   retries: 3
   until: kubeadm_join_control_plane is succeeded
+  failed_when:
+    - kubeadm_join_control_plane.rc != 0
+    - '"field is immutable" not in kubeadm_join_control_plane.stderr'
+    - '"unable to create/update the DNS service" not in kubeadm_join_control_plane.stdaerr'
   when:
     - inventory_hostname != groups['kube-master']|first
     - kubeadm_already_run is not defined or not kubeadm_already_run.stat.exists

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

@@ -24,7 +24,10 @@
   retries: 3
   until: kubeadm_upgrade.rc == 0
   when: inventory_hostname == groups['kube-master']|first
-  failed_when: kubeadm_upgrade.rc != 0 and "field is immutable" not in kubeadm_upgrade.stderr
+  failed_when:
+    - kubeadm_upgrade.rc != 0
+    - '"field is immutable" not in kubeadm_upgrade.stderr'
+    - '"unable to create/update the DNS service" not in kubeadm_upgrade.stderr'
   environment:
     PATH: "{{ bin_dir }}:{{ ansible_env.PATH }}"
   notify: Master | restart kubelet
@@ -44,6 +47,8 @@
   failed_when:
     - kubeadm_upgrade.rc != 0
     - '"field is immutable" not in kubeadm_upgrade.stderr'
+    - '"unable to create/update the DNS service" not in kubeadm_upgrade.stderr'
+    - kubeadm_upgrade.stdout_lines | length > 1
   environment:
     PATH: "{{ bin_dir }}:{{ ansible_env.PATH }}"
   notify: Master | restart kubelet
@@ -72,3 +77,19 @@
     - kubeadm_scale_down_coredns_enabled
     - dns_mode not in ['coredns', 'coredns_dual']
   changed_when: false
+
+- name: kubeadm | Remove kube-dns service if kubeadm upgrade created it
+  command: >-
+    {{ bin_dir }}/kubectl
+    --kubeconfig /etc/kubernetes/admin.conf
+    -n kube-system
+    delete svc kube-dns
+  register: delete_svc_kube_dns
+  retries: 6
+  delay: 2
+  until: delete_svc_kube_dns is succeeded
+  run_once: yes
+  when:
+    - dns_mode not in ['coredns', 'coredns_dual']
+  failed_when: false
+  changed_when: false