Ansible-playbook简单应用的几个实例

①ansible-playbook的循环:

  重复执行某任务;对迭代项的引用,固定变量名为“item”,而后要在task中使用with_items给定要迭代的元素列表,列表方法:字符串/字典(类似json)  

- hosts: all
  remote_user: root
  tasks:
        - name: add some groups
          group: name={{ item }} state=present
          with_items:
          - demo1
          - demo2
          - demo3
        - name: add some users
          user: name={{ item.name }} group={{ item.group }} state=present  //模块中调用的相关参数赋值时前后均无空格
          with_items:
                - { name: 'user1',group: 'demo1'}  
                - { name: 'user2',group: 'demo2'}
                - { name: 'user3',group: 'demo3'}  ////此处key后面的:与value之间要有一个空格,否则为语法错误

②ansible-playbook的条件判断:

  相当于编程语言中的if语句,不过在ansible中要使用when语句,且要定义在tasks中

- hosts: all
  remote_user: root
  tasks:
    - name: Install httpd conf file to httpd2.2
      template: src=file/httpd.conf.c6.j2 dest=/etc/httpd/conf/httpd.conf
      when: ansible_distribution_major_version == "6"
    - name: Install httpd conf file to httpd2.4
      template: src=file/httpd.conf.c7.j2 dest=/etc/httpd/conf/httpd.conf
      when: ansible_distribution_major_version == "7"
    - name: Start httpd
      service: name=httpd state=started enabled=true

③ansible-playbook限定执行范围:

  当playbook指定的一批主机中有个别主机需进行变更时,不用修改playbook本身,可通过一些命令选项直接进行限定ansible-playbook的命令执行范围。

  --limit选项:  

ansible-playbook test1.yaml --limit node2
//此时,ansbile-playbook中的hosts即便定义了all,也不会在node2这个组上执行playbook

  或者直接在playbook的yaml文件中显式定义hosts要执行的主机,如:

    指定单台主机:www.a.com

    指定多台主机:www.a.com,www,b.com

    指定一组主机:dbserver

  也可以在执行playbook前先查看受影响的主机有哪些:

[root@node1 work]# ansible-playbook test2.yaml --list-hosts

playbook: test2.yaml

  play #1 (all): all    TAGS: []
    pattern: [u'all']
    hosts (2):
      node3
      node2

④ansible加密模块Vault

  在执行某些任务时,难免会触及到一些密码或敏感数据,此时需要对相关任务进行加密,ansible自带的Vault可满足大部分需求。

  使用ansible-vault命令给文件加密:

[root@node1 work]# ansible-vault encrypt test5.yaml   //加密命令
New Vault password: 
Confirm New Vault password: 
Encryption successful

  此时查看test5.yaml的内容则显示:

[root@node1 work]# cat test5.yaml 
$ANSIBLE_VAULT;1.1;AES256
32366237663533633838613431653433653061396630346633396232393265376138626630646633
6635646462346665613963303061323164623265303331610a633537393239633832383334386338
39393932633163303136353934343061363330313663633535626138613537633465326232383663
3036336337333163390a623733323635653536316335323663363736303733303362353839356164
38643665363131316631646166396634616131343835366261356130343061356438363530636364
61353764383636386438636662373665613031623366396364306262396536656362336161313630
33323437623435646133643831656433653061316439323931326134386263653665633037393037
62303865383165336362

  且直接使用ansible-playbook执行此文件会报错,需要先解密。这里列出ansible-vault命令的几个常用的选项:

ansible-vault命令的其他几个常用选项:
        edit:用于编辑ansible-vault加密过的文件
        rekey:重新修改已被加密文件的密码
        create:创建一个新文件,并直接对其进行加密
        view:查看经过加密的文件
        decrypt:解密文件

    也可以在当前登录用户的家目录下的.ansible目录中创建一个文件用于存储密码,修改这些文件的权限为600,在运行时,使用如下命令进行:

ansible-playbook test5.yaml --vault-password-file /root/.ansible/vault_pass.txt 

    // --vault-password-file PATH/TO/PASSWD_FILE 

 ⑤简单基于roles来一键部署LAMP环境

  首先看一下php的角色目录结构:

[root@node1 roles]# tree php/
php/
├── default
├── files
│   └── php-fpm.conf
├── handlers
│   └── main.yaml
├── meta
├── tasks
│   └── main.yaml
├── templates
│   └── www.conf.j2
└── vars

7 directories, 4 files

  如果使用yum安装的php-fpm的话,其配置文件被切分成了两部分默认的话,如果基于默认配置的话,则无需修改php-fpm.conf,直接修改www.conf即可。

  tasks/main.yaml的内容如下:

- name: install php
  yum: name=php,php-fpm  state=present
- name: create php-fpm group
  group: name=www state=present
- name: create php-fpm user
  user: name=www group=www state=present
- name: install conf file1
  copy: src=php-fpm.conf dest=/etc/php-fpm.conf
- name: install conf file
  template: src=www.conf.j2 dest=/etc/php-fpm.d/www.conf
  notify: restart php-fpm
  tags: init conf file
- name: start php-fpm
  service: name=php-fpm state=started

  handlers/main.yaml的内容如下:

- name: restart php-fpm
  service: name=php-fpm state=restarted

  templates/www.conf.j2的内容如下:

listen = {{ ansible_eno16777736.ipv4.address }}:9000

//仅做测试演示的话,只修改此项即可。

  再来看下httpd的角色目录结构:

[root@node1 httpd]# tree
.
├── default
├── files
│   └── index.php    //php测试页
├── handlers
│   └── main.yaml
├── meta
├── tasks
│   └── main.yaml
├── templates
│   ├── httpd.conf.j2   //httpd的主配置文件
│   └── php.conf.j2     //此处是基于虚拟主机的php配置
└── vars
    └── main.yaml

7 directories, 6 files

  tasks/main.yaml的内容如下:

- name: install htppd
  yum: name=httpd state=present
- name: install conf file
  template: src=httpd.conf.j2 dest=/etc/httpd/conf/httpd.conf  src=php.conf.j2 dest=/etc/httpd/conf.d/php.conf.j2
  notify: restart httpd
  tags: change conf file
- name: init index.php
  copy: src=index.php dest=/var/www/html/index.php
- name: start httpd
  service: name=httpd state=started enabled=true

  templates/php.conf.j2的内容如下(基于httpd2.4的配置):

DirectoryIndex index.php
<VirtualHost *:80>
        ServerName www.phptest.com
        DocumentRoot "/var/www/html"
        ProxyRequests Off
        ProxyPassMatch ^/(.*.php)$ fcgi://localhost:9000/var/www/html/$1
        <Directory "/var/www/html">
                Options None
                AllowOverride None
                Require all granted
        </Directory>
</VirtualHost>

  mysql的角色目录结构大同小异,可自行基于rpm包安装或者其他安装方式定义角色文件即可。

  写好角色后,再定义一个任务,跑一下即可,此处任务文件为/etc/ansible/work/role_lamp.yaml,内容如下:

- hosts: two
  remote_user: root
  roles:
  - httpd
  - php
  - mysql

  跑完后,如无报错,且测试页能访问即可。本例只是简单的陈述了下大体的角色架构,里面还有很多需要细细雕琢之处,还需各位多多阅读官方文档或其他相关ansible的书籍,深入学习。

  

  

原文地址:https://www.cnblogs.com/trymybesttoimp/p/7216860.html