Edited pre-upgrade task to uncordon a node failing to drain (#6546)

roles/upgrade/pre-upgrade/tasks/main.yml

@@ -30,10 +30,11 @@
       false
       {%- endif %}
 
+- name: Node draining
+  block:
     - name: Cordon node
       command: "{{ bin_dir }}/kubectl cordon {{ kube_override_hostname|default(inventory_hostname) }}"
       delegate_to: "{{ groups['kube-master'][0] }}"
-  when: needs_cordoning
 
     - name: Check kubectl version
       command: "{{ bin_dir }}/kubectl version --client --short"
@@ -43,7 +44,6 @@
       changed_when: false
       when:
         - drain_nodes
-    - needs_cordoning
         - drain_pod_selector
 
     - name: Ensure minimum version for drain label selector if necessary
@@ -51,7 +51,6 @@
         that: "kubectl_version.stdout.split(' ')[-1] is version('v1.10.0', '>=')"
       when:
         - drain_nodes
-    - needs_cordoning
         - drain_pod_selector
 
     - name: Drain node
@@ -63,7 +62,14 @@
         --timeout {{ drain_timeout }}
         --delete-local-data {{ kube_override_hostname|default(inventory_hostname) }}
         {% if drain_pod_selector %}--pod-selector '{{ drain_pod_selector }}'{% endif %}
-  delegate_to: "{{ groups['kube-master'][0] }}"
       when:
         - drain_nodes
+  rescue:
+    - name: Set node back to schedulable
+      command: "{{ bin_dir }}/kubectl --kubeconfig /etc/kubernetes/admin.conf uncordon {{ inventory_hostname }}"
+    - name: Fail after rescue
+      fail:
+        msg: "Failed to drain node {{ inventory_hostname }}"
+  delegate_to: "{{ groups['kube-master'][0] }}"
+  when:
     - needs_cordoning