worker.yml

---
- hosts: purpose_kube_worker
  become: yes
  vars:
    master_dns: "kube1.home"
  tasks:
    - name: retrieve a token
      command: kubeadm token create --ttl 2h
      register: token_to_join
      run_once: true
      delegate_to: "{{master_dns}}"
      environment:
        KUBECONFIG: "/etc/kubernetes/admin.conf"

    - name: join cluster
      command: 
        cmd: "kubeadm join {{master_dns}}:6443 --token {{token_to_join.stdout}} --discovery-token-unsafe-skip-ca-verification"
        creates: "/etc/kubernetes/pki/ca.crt"

    - name: list nodes
      command: "kubectl get nodes -o custom-columns=NAME:.metadata.name"
      register: running_nodes
      delegate_to: "{{master_dns}}"
      environment:
        KUBECONFIG: "/etc/kubernetes/admin.conf"
      changed_when: false

    - fail:
        msg: "Could not find node {{ansible_hostname}} in the cluster."
      when: ansible_hostname not in running_nodes.stdout_lines
      run_once: true