通过Ansible来搭建一套Web服务架构。
Inventory文件内容如下：
[proxy]
192.168.40.254
[app]
192.168.40.243
[nosql]
192.168.40.252
[db]
192.168.40.252
（1）首先使用ansible安装Nginx。
ansible proxy -m yum -a "name=nginx state=present"
使用yum模块来安装CentOS上的包。特别要注意state的意思。
从网络安装：
ansible proxy -m yum -a "name=http://nginx.org/packages/centos/6/noarch/RPMS/nginx-release-centos-6.0.el6.ngx.noarch.rpm state=present"
从本地安装：
ansible proxy -m yum -a "name=/usr/local/src/nginx-release-centos-6-0.el6.ngx.noarch.rpm state=present"
（2）然后部署apps服务器。
=== nginx和php
ansible app -m yum -a "name=nginx state=present"
ansible app -m yum -a "name=php state=present"
=== django
ansible app -m yum -a "name=MySQL-python state=present"
ansible app -m yum -a "name=python-setuptools state=present"
ansible app -m pip -a "name=django state=present"
ansible app -m command -a "python -c 'import django; print django.get_version()' "