Question

在ansible playbook中，如果需要升级，我想停止MariaDB（从我的情况下，从RPM包中重新启动并不总是有效）。我对ansible很新。

我想出了这个：

- name: "Check if MariaDB needs to be upgraded"
  shell: "yum check-update MariaDB-server|grep MariaDB|wc -l"
  register: needs_update

- name: "Stop mysql service"
  service:
  name: mysql
  state: stopped
when: needs_update.stdout == "1"

有没有更好的方法来执行此操作然后执行shell命令？运行时我会收到警告：

TASK [mariadb_galera : Check if MariaDB needs to be upgraded]    ******************
changed: [139.162.220.42] => {"changed": true, "cmd": "yum check-update MariaDB-server|grep MariaDB|wc -l", "delta": "0:00:00.540862", "end": "2017-03-01 13:03:34.415272", "rc": 0, "start": "2017-03-01 13:03:33.874410", "stderr": "", "stdout": "0", "stdout_lines": ["0"], "warnings": ["Consider using yum module rather than running yum"]}
 [WARNING]: Consider using yum module rather than running yum

谢谢！

Answer 1

您可以使用以下隐藏警告：

- name: "Check if MariaDB needs to be upgraded"
  shell: "yum check-update MariaDB-server|grep MariaDB|wc -l"
  args:
    warn: false
  register: needs_update

或者你可以欺骗Ansible在yum中执行check_mode任务：

- name: "Check if MariaDB needs to be upgraded (CHECK MODE!)"
  yum:
    name: MariaDB-server
    state: latest
  check_mode: yes
  register: needs_update_check

- name: "Stop mysql service"
  service:
    name: mysql
    state: stopped
  when: needs_update_check | changed

请在使用前测试此代码。

Answer 2

处理此问题的最佳方法是使用＆＃34;处理程序＆＃34;

中的某些内容

tasks:
  - name: Update db
    yum: name=MariaDB-server state=latest
    notify:
      - stop db

handlers:
  -  name: stop db  
     service: name=MariaDB-server state=stopped

如果需要执行多项操作，可以指定多个处理程序，但如果只想重新启动数据库，请使用restarted而不是停止

http://docs.ansible.com/ansible/playbooks_best_practices.html

只有在需要升级时才能以可靠的方式停止服务

2 个答案: