ansible变量注册register
ansible变量注册register就是在执行的playbook中如果想获取某些信息，但是plabybook又不支持输出的情况下使用，这个时候使用register把想要获取的输入的信息放到一个变量中，然后通过这个变量再输出
示例：安装启动httpd的同时想要查看httpd的启动状态
这里通过shell模块执行 ps aux 命 令
- hosts: devops
tasks:
- name: install httpd
yum:
name:
- httpd
state:
present
- name: start httpd
service:
name: httpd
state: started
- name: check httpd status
shell:
ps aux|grep httpd
但是没有得到我们想要的输出
$ ansible-playbook install_httpd.yml
PLAY [devops] ******************************************************************************************************************************************
TASK [Gathering Facts] *********************************************************************************************************************************
ok: [devops02]
ok: [devops03]
ok: [devops01]
TASK [install httpd] ***********************************************************************************************************************************
ok: [devops02]
ok: [devops03]
ok: [devops01]
TASK [start httpd] *************************************************************************************************************************************
ok: [devops02]
ok: [devops03]
ok: [devops01]
TASK [check httpd status] ******************************************************************************************************************************
changed: [devops02]
changed: [devops03]
changed: [devops01]
PLAY RECAP *********************************************************************************************************************************************
devops01 : ok=4 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
devops02 : ok=4 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
devops03 : ok=4 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
修改一下yml文件
- hosts: devops
tasks:
- name: install httpd
yum:
name:
- httpd
state:
present
- name: start httpd
service:
name: httpd
state: started
- name: check httpd status
shell:
ps aux|grep httpd
# 这里增加一个register关键字，下边是变量的名称
# register的作用是接收上一步shell模块的输出
register:
check_httpd
- name: print output
debug:
msg:
"{{ check_httpd }}"
可以看到有很多的输出，如果不想看到所有的输出，则需要指定关键字输出
$ ansible-playbook install_httpd.yml
PLAY [devops] ******************************************************************************************************************************************
TASK [Gathering Facts] *********************************************************************************************************************************
ok: [devops02]
ok: [devops03]
ok: [devops01]
TASK [install httpd] ***********************************************************************************************************************************
ok: [devops02]
ok: [devops03]
ok: [devops01]
TASK [start httpd] *************************************************************************************************************************************
ok: [devops02]
ok: [devops03]
ok: [devops01]
TASK [check httpd status] ******************************************************************************************************************************
changed: [devops02]
changed: [devops03]
changed: [devops01]
TASK [print output] ************************************************************************************************************************************
ok: [devops01] => {
"msg": {
"changed": true,
"cmd": "ps aux|grep httpd",
"delta": "0:00:00.042416",
"end": "2021-09-12 23:11:20.304771",
"failed": false,
"rc": 0,
"start": "2021-09-12 23:11:20.262355",
"stderr": "",
"stderr_lines": [],
"stdout": "root 25808 0.0 0.1 224080 5036 ? Ss 22:31 0:00 /usr/sbin/httpd -DFOREGROUND\napache 25810 0.0 0.0 226164 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND\napache 25811 0.0 0.0 226164 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND\napache 25812 0.0 0.0 226164 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND\napache 25813 0.0 0.0 226164 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND\napache 25814 0.0 0.0 226164 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND\nroot 30483 17.4 1.1 392188 44092 pts/0 Sl+ 23:11 0:00 /usr/bin/python2 /usr/bin/ansible-playbook install_httpd.yml\nroot 31578 6.0 1.1 395864 41904 pts/0 S+ 23:11 0:00 /usr/bin/python2 /usr/bin/ansible-playbook install_httpd.yml\nroot 31580 14.0 1.3 403088 49884 pts/0 S+ 23:11 0:00 /usr/bin/python2 /usr/bin/ansible-playbook install_httpd.yml\nroot 31591 7.0 1.0 394384 40928 pts/0 S+ 23:11 0:00 /usr/bin/python2 /usr/bin/ansible-playbook install_httpd.yml\nroot 31840 0.0 0.0 113280 1196 pts/4 S+ 23:11 0:00 /bin/sh -c ps aux|grep httpd\nroot 31844 0.0 0.0 112812 948 pts/4 S+ 23:11 0:00 grep httpd",
"stdout_lines": [
"root 25808 0.0 0.1 224080 5036 ? Ss 22:31 0:00 /usr/sbin/httpd -DFOREGROUND",
"apache 25810 0.0 0.0 226164 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND",
"apache 25811 0.0 0.0 226164 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND",
"apache 25812 0.0 0.0 226164 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND",
"apache 25813 0.0 0.0 226164 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND",
"apache 25814 0.0 0.0 226164 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND",
"root 30483 17.4 1.1 392188 44092 pts/0 Sl+ 23:11 0:00 /usr/bin/python2 /usr/bin/ansible-playbook install_httpd.yml",
"root 31578 6.0 1.1 395864 41904 pts/0 S+ 23:11 0:00 /usr/bin/python2 /usr/bin/ansible-playbook install_httpd.yml",
"root 31580 14.0 1.3 403088 49884 pts/0 S+ 23:11 0:00 /usr/bin/python2 /usr/bin/ansible-playbook install_httpd.yml",
"root 31591 7.0 1.0 394384 40928 pts/0 S+ 23:11 0:00 /usr/bin/python2 /usr/bin/ansible-playbook install_httpd.yml",
"root 31840 0.0 0.0 113280 1196 pts/4 S+ 23:11 0:00 /bin/sh -c ps aux|grep httpd",
"root 31844 0.0 0.0 112812 948 pts/4 S+ 23:11 0:00 grep httpd"
]
}
}
ok: [devops02] => {
"msg": {
"changed": true,
"cmd": "ps aux|grep httpd",
"delta": "0:00:00.037817",
"end": "2021-09-12 23:11:20.254390",
"failed": false,
"rc": 0,
"start": "2021-09-12 23:11:20.216573",
"stderr": "",
"stderr_lines": [],
"stdout": "root 3190 0.0 0.4 224084 5036 ? Ss 22:33 0:00 /usr/sbin/httpd -DFOREGROUND\napache 3191 0.0 0.3 226168 3092 ? S 22:33 0:00 /usr/sbin/httpd -DFOREGROUND\napache 3192 0.0 0.3 226168 3092 ? S 22:33 0:00 /usr/sbin/httpd -DFOREGROUND\napache 3193 0.0 0.3 226168 3092 ? S 22:33 0:00 /usr/sbin/httpd -DFOREGROUND\napache 3194 0.0 0.3 226168 3092 ? S 22:33 0:00 /usr/sbin/httpd -DFOREGROUND\napache 3195 0.0 0.3 226168 3092 ? S 22:33 0:00 /usr/sbin/httpd -DFOREGROUND\nroot 9953 0.0 0.1 113280 1196 pts/1 S+ 23:11 0:00 /bin/sh -c ps aux|grep httpd\nroot 9955 0.0 0.0 112808 952 pts/1 S+ 23:11 0:00 grep httpd",
"stdout_lines": [
"root 3190 0.0 0.4 224084 5036 ? Ss 22:33 0:00 /usr/sbin/httpd -DFOREGROUND",
"apache 3191 0.0 0.3 226168 3092 ? S 22:33 0:00 /usr/sbin/httpd -DFOREGROUND",
"apache 3192 0.0 0.3 226168 3092 ? S 22:33 0:00 /usr/sbin/httpd -DFOREGROUND",
"apache 3193 0.0 0.3 226168 3092 ? S 22:33 0:00 /usr/sbin/httpd -DFOREGROUND",
"apache 3194 0.0 0.3 226168 3092 ? S 22:33 0:00 /usr/sbin/httpd -DFOREGROUND",
"apache 3195 0.0 0.3 226168 3092 ? S 22:33 0:00 /usr/sbin/httpd -DFOREGROUND",
"root 9953 0.0 0.1 113280 1196 pts/1 S+ 23:11 0:00 /bin/sh -c ps aux|grep httpd",
"root 9955 0.0 0.0 112808 952 pts/1 S+ 23:11 0:00 grep httpd"
]
}
}
ok: [devops03] => {
"msg": {
"changed": true,
"cmd": "ps aux|grep httpd",
"delta": "0:00:00.037784",
"end": "2021-09-12 23:11:20.266617",
"failed": false,
"rc": 0,
"start": "2021-09-12 23:11:20.228833",
"stderr": "",
"stderr_lines": [],
"stdout": "root 25572 0.0 0.4 224084 5036 ? Ss 22:31 0:00 /usr/sbin/httpd -DFOREGROUND\napache 25573 0.0 0.3 226168 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND\napache 25574 0.0 0.3 226168 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND\napache 25575 0.0 0.3 226168 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND\napache 25576 0.0 0.3 226168 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND\napache 25577 0.0 0.3 226168 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND\nroot 30803 0.0 0.1 113280 1196 pts/0 S+ 23:11 0:00 /bin/sh -c ps aux|grep httpd\nroot 30805 0.0 0.0 112808 952 pts/0 S+ 23:11 0:00 grep httpd",
"stdout_lines": [
"root 25572 0.0 0.4 224084 5036 ? Ss 22:31 0:00 /usr/sbin/httpd -DFOREGROUND",
"apache 25573 0.0 0.3 226168 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND",
"apache 25574 0.0 0.3 226168 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND",
"apache 25575 0.0 0.3 226168 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND",
"apache 25576 0.0 0.3 226168 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND",
"apache 25577 0.0 0.3 226168 3092 ? S 22:31 0:00 /usr/sbin/httpd -DFOREGROUND",
"root 30803 0.0 0.1 113280 1196 pts/0 S+ 23:11 0:00 /bin/sh -c ps aux|grep httpd",
"root 30805 0.0 0.0 112808 952 pts/0 S+ 23:11 0:00 grep httpd"
]
}
}
PLAY RECAP *********************************************************************************************************************************************
devops01 : ok=5 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
devops02 : ok=5 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
devops03 : ok=5 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
msg输出的关键字说明
| 关键字 | 说明 |
|---|---|
| changed | 是否改变 |
| cmd | register上一步执行的命令 |
| delta | 执行花费的时间 |
| end | 结束时间 |
| failed | 是否失败 |
| rc | 返回0表明执行成功，返回1表明执行失败 |
| start | 开始时间 |
| stderr | 错误输出 |
| stderr_lines | 错误输出，以行展示 |
| stdout | 输出信息 |
| stdout_lines | 输出信息，以行展示 |
再次修改yml文件，这次我们只获取rc信息
- hosts: devops
tasks:
- name: install httpd
yum:
name:
- httpd
state:
present
- name: start httpd
service:
name: httpd
state: started
- name: check httpd status
shell:
ps aux|grep httpd
# 这里增加一个register关键字，下边是变量的名称
# register的作用是接收上一步shell模块的输出
register:
check_httpd
- name: print output
debug:
msg:
# 变量.关键字 就是输出指定的信息
"{{ check_httpd.rc }}"
可以看到，只输出了rc的相关信息
$ ansible-playbook install_httpd.yml
PLAY [devops] ******************************************************************************************************************************************
TASK [Gathering Facts] *********************************************************************************************************************************
ok: [devops02]
ok: [devops03]
ok: [devops01]
TASK [install httpd] ***********************************************************************************************************************************
ok: [devops02]
ok: [devops03]
ok: [devops01]
TASK [start httpd] *************************************************************************************************************************************
ok: [devops02]
ok: [devops03]
ok: [devops01]
TASK [check httpd status] ******************************************************************************************************************************
changed: [devops02]
changed: [devops03]
changed: [devops01]
TASK [print output] ************************************************************************************************************************************
ok: [devops01] => {
"msg": "0"
}
ok: [devops02] => {
"msg": "0"
}
ok: [devops03] => {
"msg": "0"
}
PLAY RECAP *********************************************************************************************************************************************
devops01 : ok=5 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
devops02 : ok=5 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
devops03 : ok=5 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
ansible变量注册register的使用步骤如下
1.ansible playbook在某些情况下无法直接输出，因此使用register来获取我们想要的输出结果，例如想要获取shell模块执行的命令的输出
2.register的作用就是将命令的输出保存到一个变量中，变量名任意
3.通过debug模块的msg方法输出全部结果，如果想要指定某些字段的输出，则需要使用 变量名.关键字 的方法来获取指定的输出
- name: check httpd status
shell:
ps aux|grep httpd
# 这里增加一个register关键字，下边是变量的名称
# register的作用是接收上一步shell模块的输出
register:
check_httpd
- name: print output
debug:
msg:
# 变量.关键字 就是输出指定的信息
"{{ check_httpd.rc }}"