欢迎加入 “全栈运维答疑群 632578555” ，希望能在群里对于大家的运维问题能到得到很好的解答。
还记得在上节中说到ansible安装完成之后通过 ansible --version来验证ansible是否安装OK
root@pts/0 # ansible --version
ansible 2.5.2
config file = /etc/ansible/ansible.cfg
configured module search path = [u'/root/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
ansible python module location = /usr/lib/python2.7/site-packages/ansible
executable location = /usr/bin/ansible
python version = 2.7.5 (default, Aug 4 2017, 00:39:18) [GCC 4.8.5 20150623 (Red Hat 4.8.5-16)]
配置路径说明
从这里我们可以看到 ansible 的配置文件是 /etc/ansible/ansible.cfg 以及一些其他信息。这里介绍ansible几个常用到的配置和目录。
- /etc/ansible
ansible 主配置目录，下面的ansible.cfg 是主配置文件，hosts是Inventory主机信息配置文件，roles 是配置playbook用到的。ansible所有的配置都会存放到这个目录下
root@pts/0 # ls -l /etc/ansible/
total 28
-rw-r--r--. 1 root root 19315 Apr 27 04:20 ansible.cfg
-rw-r--r--. 1 root root 1016 Apr 27 04:20 hosts
drwxr-xr-x. 2 root root 4096 Apr 27 04:20 roles
/usr/bin/pythonxx/site-packages/ansible
了解Python的同学都知道，/usr/bin/pythonxx/site-packages是Python安装包存放的地方，ansible是Python开发的，当然其先关的lib库文件和模块文件也会存放到这里。想研究源码的同学可以从这里看到源码或者从GitHub上面clone/root/.ansible/plugins/modules 和 /usr/share/ansible/plugins/modules
ansible自定义的插件模块存放的路径，/usr/local/doc/ansible/
+/usr/share/man/man1/
下面这两个目录对Linux了解的同学就知道这个是Linux下存放文档和帮助文件的地方。不做深入了解
ansible.cfg 解析
ansible.cfg 是标准的ini 文件格式，通过如下命令解析我们可以了解它有几个部分
root@pts/0 # cat /etc/ansible/ansible.cfg |egrep -v '^#'|grep '\['
[defaults]
[inventory]
[privilege_escalation]
[paramiko_connection]
[ssh_connection]
[persistent_connection]
[accelerate]
[selinux]
[colors]
[diff]
defaults
配置文件中 defaults 部分是最多的，这里只列举说明关键的配置项
[defaults]
# some basic default values...
#inventory = /etc/ansible/hosts # 定义Inventory 主机列表的
#library = /usr/share/my_modules/
#module_utils = /usr/share/my_module_utils/
#remote_tmp = ~/.ansible/tmp # 临时文件远程主机存放目录
#local_tmp = ~/.ansible/tmp # 临时文件本地存放目录
#plugin_filters_cfg = /etc/ansible/plugin_filters.yml
#forks = 5 # 默认开启的并发数
#poll_interval = 15 # 默认轮询时间间隔
#sudo_user = root # 默认的sudo用户
#ask_sudo_pass = True # 是否需要sudo密码
#ask_pass = True
#transport = smart
#remote_port = 22
#module_lang = C
#module_set_locale = False
# additional paths to search for roles in, colon separated
#roles_path = /etc/ansible/roles # 默认的下载roles 存放目录
... ...
这里需要说明几点
配置文件的大部分配置项都有明确的注释，比如上面的 roles_path，相信大家都能看懂配置文件中所有配置项都可以通过命令行指定具体的值来覆盖-
ansible读取配置配置文件的顺序是
当前执行命令目录 -> 用户家目录下.ansible.cfg（$HOME/.ansible.cfg） -> /etc/ansible.cfg
Inventory
针对Inventory主机列表的一些配置
[inventory]
# enable inventory plugins, default: 'host_list', 'script', 'yaml', 'ini'
#enable_plugins = host_list, virtualbox, yaml, constructed
# ignore these extensions when parsing a directory as inventory source
#ignore_extensions = .pyc, .pyo, .swp, .bak, ~, .rpm, .md, .txt, ~, .orig, .ini, .cfg, .retry
# ignore files matching these patterns when parsing a directory as inventory source
#ignore_patterns=
# If 'true' unparsed inventory sources become fatal errors, they are warnings otherwise.
#unparsed_is_failed=False
privilege_escalation
这里主要是针对普通用户给予sudo权限而做的配置，因为不是所有公司都会用root权限来部署应用
[privilege_escalation]
#become=True ## 是否sudo
#become_method=sudo
#become_user=root
#become_ask_pass=False
paramiko_connection
因为目前ansible默认的连接方式为openssh ，paramiko已经逐渐淡化，所以可以不用了解
ssh_connection
ansible 采用openssh 协议，底层调用的还是Linux的ssh协议，这里配置一些关于ssh连接相关的配置
[ssh_connection]
# ssh arguments to use
# Leaving off ControlPersist will result in poor performance, so use
# paramiko on older platforms rather than removing it, -C controls compression use
#ssh_args = -C -o ControlMaster=auto -o ControlPersist=60s
# The base directory for the ControlPath sockets.
# This is the "%(directory)s" in the control_path option
#
# Example:
# control_path_dir = /tmp/.ansible/cp
#control_path_dir = ~/.ansible/cp
... ...
persistent_connection
主要针对持久化长连接和超时相关的配置
persistent_connection]
# Configures the persistent connection timeout value in seconds. This value is
# how long the persistent connection will remain idle before it is destroyed.
# If the connection doesn't receive a request before the timeout value
# expires, the connection is shutdown. The default value is 30 seconds.
#connect_timeout = 30
# Configures the persistent connection retry timeout. This value configures the
# the retry timeout that ansible-connection will wait to connect
# to the local domain socket. This value must be larger than the
# ssh timeout (timeout) and less than persistent connection idle timeout (connect_timeout).
# The default value is 15 seconds.
#connect_retry_timeout = 15
# The command timeout value defines the amount of time to wait for a command
# or RPC call before timing out. The value for the command timeout must
# be less than the value of the persistent connection idle timeout (connect_timeout)
# The default value is 10 second.
#command_timeout = 10
accelerate
在使用过程中有些人反馈ansible会出现卡顿的情况，新版本官网对其做了加速优化，就有了这个配置选项，加你保持默认即可
selinux
结合Linux的selinux规则来，记住保持默认就好
colors
顾名思义就是定义ansible输出结果的颜色，可以保持默认就好
[colors]
#highlight = white
#verbose = blue
#warn = bright purple
#error = red
#debug = dark gray
#deprecate = purple
#skip = cyan
#unreachable = red
#ok = green
#changed = yellow
#diff_add = green
#diff_remove = red
#diff_lines = cyan
diff
[diff]
# Always print diff when running ( same as always running with -D/--diff )
# always = no
# Set how many context lines to show in diff
# context = 3
重点
其实看了这么多配置，对于初学者而已，一个建议：
安装好之后配置文件不需要做任何修改，我们就可以正常的使用ansible来批量自动化执行。
但是了解了相关参数对于后续高阶的学习还是有必要的嘛~