ansible 变量检测是否定义

如果需要的变量没有定义，那么可以skip或者使用jinja2的defined如下所示：

tasks:     - shell: echo "I've got '{{ foo }}' and am not afraid to use it!"       when: foo is defined     - fail: msg="Bailing out. this play requires 'bar'"       when: bar is undefined

---
- name: echo variable
  when:
    - api_interface is defined
    - neutron_external_interface is defined
    - storage_interface is undefined
  pause: seconds=10
 

 

参考：https://blog.youkuaiyun.com/kellyseeme/article/details/50609591