Ansible默认安装好后有一个配置文件/etc/ansible/ansible.cfg，该配置文件中定义了ansible的主机的默认配置部分，如默认是否需要输入密码、是否开启sudo认证、action_plugins插件的位置、hosts主机组的位置、是否开启log功能、默认端口、key文件位置等等。
具体如下：
[defaults]
# some basic default values...
hostfile = /etc/ansible/hosts \\指定默认hosts配置的位置
# library_path = /usr/share/my_modules/
remote_tmp = $HOME/.ansible/tmp
pattern = *
forks = 5
poll_interval = 15
sudo_user = root \\远程sudo用户
#ask_sudo_pass = True \\每次执行ansible命令是否询问ssh密码
#ask_pass = True \\每次执行ansible命令时是否询问sudo密码
transport = smart
remote_port = 22
module_lang = C
gathering = implicit
host_key_checking = False \\关闭第一次使用ansible连接客户端是输入命令提示
log_path = /var/log/ansible.log \\需要时可以自行添加。chown -R root:root ansible.log
system_warnings = False \\关闭运行ansible时系统的提示信息，一般为提示升级
# set plugin path directories here, separate with colons
action_plugins = /usr/share/ansible_plugins/action_plugins
callback_plugins = /usr/share/ansible_plugins/callback_plugins
connection_plugins = /usr/share/ansible_plugins/connection_plugins
lookup_plugins = /usr/share/ansible_plugins/lookup_plugins
vars_plugins = /usr/share/ansible_plugins/vars_plugins
filter_plugins = /usr/share/ansible_plugins/filter_plugins
fact_caching = memory
[accelerate]
accelerate_port = 5099
accelerate_timeout = 30
accelerate_connect_timeout = 5.0
# The daemon timeout is measured in minutes. This time is measured
# from the last activity to the accelerate daemon.
accelerate_daemon_timeout = 30如果在对之前未连接的主机进行连结时报错如下：
ansible test -a 'uptime'
192.168.1.1| FAILED =>Using a SSH password instead of a key is not possible because HostKey checking is enabled and sshpass does not support this.Please add this host's fingerprint to your known_hosts file to manage this host.
192.168.1.2 | FAILED => Using a SSH password instead of a key is not possible because Host Key checking is enabled and sshpass does not support this. Please add this host's fingerprint to your known_hosts file to manage this host.是由于在本机的~/.ssh/known_hosts文件中并有fingerprint key串，ssh第一次连接的时候一般会提示输入yes 进行确认为将key字符串加入到 ~/.ssh/known_hosts 文件中。
方法1：
在进行ssh连接时，可以使用-o参数将StrictHostKeyChecking设置为no，使用ssh连接时避免首次连接时让输入yes/no部分的提示。通过查看ansible.cfg配置文件，发现如下行：
[ssh_connection]
# ssh arguments to use
# Leaving off ControlPersist will result in poor performance, so use
# paramiko on older platforms rather than removing it
#ssh_args = -o ControlMaster=auto -o ControlPersist=60s可以启用ssh_args 部分，使用下面的配置，避免上面出现的错误：
ssh_args = -o ControlMaster=auto -o ControlPersist=60s -o StrictHostKeyChecking＝no
方法2：
在ansible.cfg配置文件中，也会找到如下配置：
# uncomment this to disable SSH key host checking
host_key_checking = False
默认host_key_checking部分是注释的，通过找开该行的注释，同样也可以实现跳过ssh 首次连接提示验证部分。但在实际测试中，似乎并没有效果，建议使用方法1.
其他部分
默认ansible 执行的时候，并不会输出日志到文件，不过在ansible.cfg 配置文件中有如下行：
log_path = /var/log/ansible.log
默认log_path这行是注释的，打开该行的注释，所有的命令执行后，都会将日志输出到/var/log/ansible.log文件。
