ansible-playbook 使用blockinfile 修改/etc/hosts 主机名

---  
- hosts: k8s-cluster
  any_errors_fatal: "{{ any_errors_fatal | default(true) }}"
  vars:
    dns_domain: cluster.local
  tasks:
    - name: populate inventory into hosts file
      blockinfile:
        path: /etc/hosts
        block: |-
          {% for item in (groups['k8s-cluster'] + groups['etcd'] + groups['calico-rr']|default([]))|unique -%}
          {{ hostvars[item]['ip'] }}  {{ item }}.{{ dns_domain }} {{ item }}
          {% endfor %}
        state: present
        create: yes
        backup: yes
        unsafe_writes: yes
        marker: "# Ansible inventory hosts {mark}"