1、实验环境中的3台服务器
host1:192.168.34.7
host2:192.168.34.17
host3:192.168.34.27
2、在host1上安装ansible

 yum -y install ansible

3、创建一个名为app的roles

cd /etc/ansible/roles/
mkdir -pv app/{vars,tasks,files,templates,handlers,defaults,meta}

4、在各目录中编辑相应的文件，具体文件如下

[root@localhost roles]# tree
.
└── app
    ├── defaults
    ├── files
    │   └── my.cnf
    ├── handlers
    │   └── main.yml
    ├── meta
    ├── tasks
    │   └── main.yml
    ├── templates
    │   └── httpd.conf.j2
    └── vars
        └── main.yml

5、在此例中，httpd的配置文件需要调用变量，所以放在templates目录下，并使用j2后缀名
mariadb的配置文件没有调用变量，所以放在files目录中。
6、创建要使用的变量

[root@localhost roles]# cat app/vars/main.yml 
servicetype: httpd
httpdpath: /data/httpd

7、在httpd.conf.j2中调用相关变量

DocumentRoot "{{ httpdpath }}/html"
<Directory "{{ httpdpath }}">
    AllowOverride None
    Require all granted
</Directory>
<Directory "{{ httpdpath }}/html">
    Options Indexes FollowSymLinks
    AllowOverride None
    Require all granted
</Directory>

8、配置task任务

[root@localhost roles]# cat app/tasks/main.yml 
- name: install httpd
  yum: 
    name: httpd
    state: installed
  when: servicetype=="httpd"

- name: make httpd dir
  file:
    state: directory
    path: "{{ httpdpath }}/html"
    mode: 755
  when: servicetype=="httpd"

- name: config httpd
  template: 
    src: httpd.conf.j2 
    dest: /etc/httpd/conf/httpd.conf
  notify: restart httpd
  when: servicetype=="httpd"

- name: start httpd
  service:
    name: httpd
    state: started
  when: servicetype=="httpd"

- name: intall mysql
  yum: 
    name: mariadb-server 
    state: installed
  when: servicetype=="mysqld"

- name: config mysql
  copy:
    src: my.cnf
    dest: /etc/my.cnf
  notify: restart mysqld
  when: servicetype=="mysqld"

- name: start mysqld
  service:
    name: mariadb
    state: started
  when: servicetype=="mysqld"

9、配置handler任务

[root@localhost roles]# cat app/handlers/main.yml 
- name: restart httpd
  service:
    name: httpd
    state: restarted

- name: restart mysqld
  service:
    name: mariadb
    state: restarted

10、在主机列表中创建两个组

[root@localhost ~]# cat /etc/ansible/hosts 
[web]
192.168.34.7
[mysql]
192.168.34.17
192.168.34.27

11、使用ansible-playbook调用roles

[root@localhost ~]# cat app.yml 
- hosts: web
  remote_user: root
  roles:
    - app

- hosts: mysql
  remote_user: root
  roles:
    - {role: app, servicetype: mysqld}
[root@localhost ~]# ansible-playbook  app.yml