Ansible定义命令行、主机/主机组、playbook等变量，注册变量和vars_prompt的用法示例
目录
一.Ansible定义变量
1.用途
2.定义规则
3.变量优先级
二.命令行定义变量
三.定义主机和主机组变量
1.主机变量
（1）内置主机变量
（2）简单示例
2.主机组变量
四.定义playbook变量
1.通过vars表示定义变量，通过' "{{变量名}}" '来引用变量
2.通过vars_file指定变量文件
五.定义host_vars和group_vars目录变量
1.主机组变量使用group_vars
2.主机变量只用host_vars
3.以主机变量简单为例演示
六.注册变量
七.vars_prompt交互变量
1.参数解析
2.简单交互案例
3.创建用户和密码示例
（1）encrypt
（2）confirm
一.Ansible定义变量
1.用途
ansible的变量主要用于存储在整个项目中重复使用的一些值，来提高创建任务和维护节点的效率
2.定义规则
变量名由字母、数字、下划线组成，由字母开头
内置关键字不能作为变量名
3.变量优先级
全局范围内命令行设置的变量>playbook及其相关配置的变量>主机和组清单的变量>ansible.cfg配置文件设置的变量
二.命令行定义变量
如上文所述，命令行使用"-e '变量名=值' "设置的变量优先级最高，下面举例演示命令行变量覆盖playbook中的变量
[root@main ~]# cat abc.yaml
---
- hosts: webservers
vars:
myservice: httpd #原本playbook内容为停掉httpd
tasks:
- name: test1
service:
name: "{{ myservice }}"
state: stopped
[root@main ~]# ansible-playbook abc.yaml -e 'myservice=chronyd'
#运行时指定变量更改为关掉chronyd
[root@main ~]# ansible webservers -m shell -a 'systemctl status httpd | grep Active'
serverb | CHANGED | rc=0 >>
Active: active (running) since Tue 2023-10-17 14:06:57 CST; 5h 22min ago
servera | CHANGED | rc=0 >>
Active: active (running) since Tue 2023-10-17 19:25:46 CST; 3min 12s ago
[root@main ~]# ansible webservers -m shell -a 'systemctl status chronyd | grep Active'
serverb | CHANGED | rc=0 >>
Active: inactive (dead) since Tue 2023-10-17 19:28:30 CST; 35s ago
servera | CHANGED | rc=0 >>
Active: inactive (dead) since Tue 2023-10-17 19:28:30 CST; 35s ago
#运行结果可以看出，停掉httpd未生效，停chonyd生效，命令行给定变量优先级高于playbook给定变量优先级三.定义主机和主机组变量
1.主机变量
（1）内置主机变量
在变量前加上"ansible_"即成为内置变量
部分内置主机关于ssh和提权的变量举例
ansible_ssh_host:指定受管节点主机真实IP地址
ansible_ssh_port:指定通过哪个端口连接受管节点
ansible_ssh_user:指定连接时使用的用户名称
ansibe_connection:指定ssh连接类型，local、ssh、paramiko
ansible_ssh_pass:ssh连接时使用的密码
ansible_ssh_executable:指定ssh指定的路径
ansible_become:允许特权升级，等同于ansible_sudo，ansible_su
ansible_become_user:提权到哪个用户，等同于ansible_sudo_user，ansible_su_user
ansbile_become_pass:需要密码时指定密码，等同于ansible_sudo_pass
ansible_sudo_exec:指定sudo命令路径（2）简单示例
[student@workstation ~]$ vim user.yml
#不属于任何组的用户
192.168.2.190 ansible_ssh_user=root ansible_user_pass='redhat'
192.168.2.191 ansible_ssh_user=root ansible_user_pass='su123'2.主机组变量
如上例，将两台受管节点相等的部分定义为一个变量
[student@workstation ~]$ vim user.yml
192.168.2.190 ansible_ssh_user=root ansible_user_pass='redhat'
192.168.2.191 ansible_ssh_user=root ansible_user_pass='su123'
#更改为
192.168.2.190 ansible_user_pass='redhat'
192.168.2.191 ansible_user_pass='su123'
[webservers:vars]
ansible_ssh_user=root四.定义playbook变量
1.通过vars表示定义变量，通过' "{{变量名}}" '来引用变量
[root@localhost ~]# cat httpd.yaml
---
- name: install httpd chrony
hosts: webservers
vars: #声明在此处定义变量
mypackages: #变量名
- httpd
- chrony
myhttpd: httpd
mychronyd: chronyd
tasks:
- name: install them
yum:
name: "{{ mypackages }}" #使用变量
state: present
- name: start httpd
service:
name: "{{ myhttpd }}"
state: started
- name: start chronyd
service:
name: "{{ mychronyd }}"
state: started
[root@localhost ~]# ansible webservers -m shell -a 'systemctl status httpd | grep Active'
serverb | CHANGED | rc=0 >>
Active: active (running) since Tue 2023-10-17 14:06:57 CST; 3min 45s ago
servera | CHANGED | rc=0 >>
Active: active (running) since Tue 2023-10-17 14:06:57 CST; 3min 45s ago
[root@localhost ~]# ansible webservers -m shell -a 'systemctl status chronyd | grep Active'
servera | CHANGED | rc=0 >>
Active: active (running) since Tue 2023-10-17 13:29:27 CST; 41min ago
serverb | CHANGED | rc=0 >>
Active: active (running) since Tue 2023-10-17 13:31:57 CST; 38min ago2.通过vars_file指定变量文件
[root@main ~]# cat myvar1.yaml #vars文件也使用yaml格式
packages:
- rpcbind
- openssl
[root@main ~]# cat httpd1.yaml
---
- name: install rpcbind openssl
hosts: webservers
tasks:
- name: install them
yum:
name: "{{ packages }}" #同样这样使用变量
state: present
vars_files: #指定vars文件
- myvar1.yaml #指定你自己的vars问文件位置，这里是当前路径下的myvars1.yaml文件
[root@main ~]# ansible-playbook httpd1.yaml --syntax-check
playbook: httpd1.yaml
[root@main ~]# ansible-playbook httpd1.yaml
[root@main ~]# ansible webservers -m shell -a 'yum list installed | grep rpcbind'
servera | CHANGED | rc=0 >>
rpcbind.x86_64 0.2.0-49.el7 @base
serverb | CHANGED | rc=0 >>
rpcbind.x86_64 0.2.0-49.el7 @base
[root@main ~]# ansible webservers -m shell -a 'yum list installed | grep openssl'
servera | CHANGED | rc=0 >>
openssl.x86_64 1:1.0.2k-19.el7 @anaconda
openssl-libs.x86_64 1:1.0.2k-19.el7 @anaconda
xmlsec1-openssl.x86_64 1.2.20-7.el7_4 @anaconda
serverb | CHANGED | rc=0 >>
openssl.x86_64 1:1.0.2k-19.el7 @anaconda
openssl-libs.x86_64 1:1.0.2k-19.el7 @anaconda
xmlsec1-openssl.x86_64 1.2.20-7.el7_4 @anaconda五.定义host_vars和group_vars目录变量
1.主机组变量使用group_vars
group_vars是一个目录，这个名称固定，必须是和你的inventory文件和ansible.cfg文件位于同一级目录，其下创建的文件需要和你主机清单中的组名称一致，在这个文件中写入变量和值
2.主机变量只用host_vars
host_vars和group_vars相同，也是一个目录，名称固定，必须和inventory文件和ansible.cfg文件位于同一级目录，其下创建的文件需要和你主机清单中的主机名称一致（清单文件中写的是主机名就写=用主机名，是IP地址就用IP地址），在这个文件中写入变量和值
3.以主机变量简单为例演示
[root@main ~]# tree /root
/root
├── anaconda-ks.cfg
├── ansible.cfg
├── group_vars
│ ├── dbservers
│ └── webservers
├── host_vars
│ ├── servera
│ └── serverb
├── httpd1.yaml
├── httpd.yaml
├── myhosts
├── myhttpd.yaml
└── myvar1.yaml
[root@main ~]# cat host_vars/servera
aname: httpd
[root@main ~]# cat host_vars/serverb
bname: mod_ssl
[root@main ~]# cat myhttpd.yaml
---
- name: stop servera httpd
hosts: servera
tasks:
- name: stop it
service:
name: "{{ aname }}" #在剧本中就可以直接用用定义好的主机变量
state: stopped
- name: install serverb mod_ssl
hosts: serverb
tasks:
- name: install it
yum:
name: "{{ bname }}"
state: present
[root@main ~]# ansible-playbook myhttpd.yaml --syntax-check
playbook: myhttpd.yaml
[root@main ~]# ansible-playbook myhttpd.yaml
[root@main ~]# ansible servera -m shell -a 'systemctl status httpd | grep Active'
servera | CHANGED | rc=0 >>
Active: inactive (dead)
[root@main ~]# ansible serverb -m shell -a 'yum list installed | grep mod_ssl'
serverb | CHANGED | rc=0 >>
mod_ssl.x86_64 1:2.4.6-99.el7.centos.1 @updates 六.注册变量
注册变量主要是使用register来捕获命令的输出，将其保存在一个临时变量中，便于进行特定操作。
如下例，将"id su"的结果注册为"su"，并使用debug模块输出su的内容，并在playbook执行后的debug结果中判断出该用户是否存在
[root@main ~]# cat iduser.yaml
---
- name: is su exist
hosts: webservers
tasks:
- name: test su
shell: id su
register: su
ignore_errors: yes #便于测试，忽略错误
- name: echo it
debug:
msg: "{{ su }}"
[root@main ~]# ansible-playbook iduser.yaml
PLAY [is su exist] ******************************************************************************************************************************
TASK [Gathering Facts] **************************************************************************************************************************
ok: [servera]
ok: [serverb]
TASK [test su] **********************************************************************************************************************************
changed: [servera]
changed: [serverb]
TASK [echo it] **********************************************************************************************************************************
ok: [servera] => {
"msg": {
"changed": true,
"cmd": "id su",
"delta": "0:00:00.004109",
"end": "2023-10-17 19:05:47.215481",
"failed": false,
"rc": 0, #为0表示存在，非0不存在
"start": "2023-10-17 19:05:47.211372",
"stderr": "",
"stderr_lines": [],
"stdout": "uid=1000(su) gid=1000(su) groups=1000(su)", #有会输出该用户的详细信息，没有会提示不存在此用户
"stdout_lines": [
"uid=1000(su) gid=1000(su) groups=1000(su)"
]
}
}
ok: [serverb] => {
"msg": {
"changed": true,
"cmd": "id su",
"delta": "0:00:00.004695",
"end": "2023-10-17 19:05:47.220915",
"failed": false,
"rc": 0,
"start": "2023-10-17 19:05:47.216220",
"stderr": "",
"stderr_lines": [],
"stdout": "uid=1000(su) gid=1000(su) groups=1000(su)",
"stdout_lines": [
"uid=1000(su) gid=1000(su) groups=1000(su)"
]
}
}
PLAY RECAP **************************************************************************************************************************************
servera : ok=3 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
serverb : ok=3 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0 七.vars_prompt交互变量
用于交互提示用户输入值
1.参数解析
prompt表示对用户的提示信息
private表示用户在输入时是否隐藏输入的信息
default表示如果用户没有输入，则此项的默认值
2.简单交互案例
[root@main ~]# cat register.yaml
---
- hosts: webservers
vars_prompt:
- name: "one"
prompt: "请输入第一个值"
private: no
- name: "two"
prompt: "请输入第二个值"
#default: 'hello'
private: yes
tasks:
- name: dis one value
debug: msg="{{one}}"
- name: dis two value
debug: msg="{{two}}"
#测试结果
[root@main ~]# ansible-playbook register.yaml
请输入第一个值: nihao
请输入第二个值: #private为yes，此处我输入时会隐藏信息
PLAY [webservers] *******************************************************************************************************************************
TASK [Gathering Facts] **************************************************************************************************************************
ok: [servera]
ok: [serverb]
TASK [dis one value] ****************************************************************************************************************************
ok: [servera] => {
"msg": "nihao"
}
ok: [serverb] => {
"msg": "nihao"
}
TASK [dis two value] ****************************************************************************************************************************
ok: [servera] => { #显示输入的信息
"msg": "hello"
}
ok: [serverb] => {
"msg": "hello"
}
PLAY RECAP **************************************************************************************************************************************
servera : ok=3 changed=0 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
serverb : ok=3 changed=0 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0 3.创建用户和密码示例
（1）encrypt
可以指定在密码处可以指定使用sha512对密码进行哈希加密
（2）confirm
可以设置重复确认密码，两次密码不符合会报“* VALUES ENTERED DO NOT MATCH ”
[root@main ~]# cat register1.yaml
---
- hosts: webservers
vars_prompt:
- name: "name"
prompt: "enter user_name"
private: no
- name: "passwd"
prompt: "enter user_passwd"
private: yes
#encrypt: "sha512_crypt"
#confirm: yes
tasks:
- name: create him
user:
name: "{{ name }}"
password: "{{ passwd }}"
[root@main ~]# ansible-playbook register1.yaml
enter user_name: sulibao
enter user_passwd:
[WARNING]: Found variable using reserved name: name
PLAY [webservers] *******************************************************************************************************************************
TASK [Gathering Facts] **************************************************************************************************************************
ok: [serverb]
ok: [servera]
TASK [create him] *******************************************************************************************************************************
[WARNING]: The input password appears not to have been hashed. The 'password' argument must be encrypted for this module to work properly.
changed: [serverb]
changed: [servera]
PLAY RECAP **************************************************************************************************************************************
servera : ok=2 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
serverb : ok=2 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
[root@main ~]# ansible webservers -a 'id sulibao'
serverb | CHANGED | rc=0 >>
uid=1001(sulibao) gid=1001(sulibao) groups=1001(sulibao)
servera | CHANGED | rc=0 >>
uid=1001(sulibao) gid=1001(sulibao) groups=1001(sulibao)
#未加密的密码
[root@main ~]# ansible webservers -m shell -a 'cat /etc/shadow | grep sulibao'
serverb | CHANGED | rc=0 >>
sulibao:ansible:19647:0:99999:7:::
servera | CHANGED | rc=0 >>
sulibao:ansible:19647:0:99999:7:::
#加密后
[root@main ~]# ansible webservers -m shell -a 'cat /etc/shadow | grep li'
serverb | CHANGED | rc=0 >>
sulibao:ansible:19647:0:99999:7:::
li:$6$U0qiY4DnzK8AWcBe$rIFmtpCr.1qU3sxtv90U2bRaZbxgqj1PK9UV4wp6W8zWXigHTfcfuFjJ0AvCZMb0Xe75juLlarm94xNZUnoCX.:19647:0:99999:7:::
servera | CHANGED | rc=0 >>
sulibao:ansible:19647:0:99999:7:::
li:$6$U0qiY4DnzK8AWcBe$rIFmtpCr.1qU3sxtv90U2bRaZbxgqj1PK9UV4wp6W8zWXigHTfcfuFjJ0AvCZMb0Xe75juLlarm94xNZUnoCX.:19647:0:99999:7:::