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

---
- name: See if node is in ready state
  shell: "{{ bin_dir }}/kubectl get nodes | grep {{ inventory_hostname }}"
  register: kubectl_nodes
  delegate_to: "{{ groups['kube-master'][0] }}"
  failed_when: false

- set_fact:
    needs_cordoning: >-
      {% if " Ready" in kubectl_nodes.stdout -%}
      true
      {%- else -%}
      false
      {%- endif %}

- name: Cordon node
  command: "{{ bin_dir }}/kubectl cordon {{ inventory_hostname }}"
  delegate_to: "{{ groups['kube-master'][0] }}"
  when: needs_cordoning

- name: Drain node
  command: >-
    {{ bin_dir }}/kubectl drain
      --force
      --ignore-daemonsets
      --grace-period {{ drain_grace_period }}
      --timeout {{ drain_timeout }}
      --delete-local-data {{ inventory_hostname }}
  delegate_to: "{{ groups['kube-master'][0] }}"
  when: needs_cordoning