默认位置
/etc/ansible/hosts
标准
mail.example.com
[webservers]
foo.example.com
bar.example.com
[dbservers]
one.example.com
two.example.com
three.example.com
# 2个主机组webservers＆dbservers，一个孤儿主机mail.example.com
非默认ssh端口
badwolf.example.com:5309
主机别名&ssh通道
jumper ansible_ssh_port=5555 ansible_ssh_host=192.168.1.50
# jumper是主机别名，连接192.168.1.50:5555端口
配置大量主机
[webservers]
www[01:50].example.com
[databases]
db-[a:f].example.com
指派连接用户和类型
[targets]
localhost ansible_connection=local
other1.example.com ansible_connection=ssh ansible_ssh_user=mpdehaan
other2.example.com ansible_connection=ssh ansible_ssh_user=mdehaan
主机变量
[atlanta]
host1 http_port=80 maxRequestsPerChild=808
host2 http_port=303 maxRequestsPerChild=909
# 变量http_port，maxRequestsPerChild用于playbook
主机组变量
[atlanta]
host1
host2
[atlanta:vars]
ntp_server=ntp.atlanta.example.com
proxy=proxy.atlanta.example.com
# 关键字:var，变量ntp_server，proxy
主机组嵌套
[atlanta]
host1
host2
[raleigh]
host2
host3
[southeast:children]
atlanta
raleigh
[southeast:vars]
some_server=foo.southeast.example.com
halon_system_timeout=30
self_destruct_countdown=60
escape_pods=2
[usa:children]
southeast
northeast
southwest
northwest
# 关键字:children
在文件存储主机及主机组变量
/etc/ansible/group_vars/raleigh
/etc/ansible/group_vars/webservers
/etc/ansible/host_vars/foosball
# 主机foosball，主机组raleigh & webservers
dynamic inventory
/etc/ansible/hosts是基于文本管理的数据，可以将inventory存储在数据库，使用http api进行交互。编写脚本将inventory数据json化。
http://docs.ansible.com/developing_inventory.html
