Ansible——处理任务失败
忽略任务失败
Ansible 默认会检查命令和模块的返回状态，并进行相应的错误处理，默认是遇到错误就中断 playbook 的执行，这些默认行为都是可以改变的，可以通过 ignore_errors 忽略返回状态码
[root@localhost project]# !vim
vim ceshi1.yml
---
- hosts: 192.168.190.134
tasks:
- command: ls /sdadadsdad 这个文件是不存在的，如果正常执行playbook会出错并不会执行下面的task
ignore_errors: yes 忽略错误
- command: echo 'hello' 继续执行此task
TASK [command] *****************************************************************************************
fatal: [192.168.190.134]: FAILED! => {"changed": true, "cmd": ["ls", "/sdadadsdad"], "delta": "0:00:00.003481", "end": "2020-09-08 09:23:22.735623", "msg": "non-zero return code", "rc": 2, "start": "2020-09-08 09:23:22.732142", "stderr": "ls: cannot access '/sdadadsdad': No such file or directory", "stderr_lines": ["ls: cannot access '/sdadadsdad': No such file or directory"], "stdout": "", "stdout_lines": []}
...ignoring
TASK [command] *****************************************************************************************
changed: [192.168.190.134]
强制执行任务
通常任务失败，playbook 会终止，那么收到 play 中之前任务通知的处理程序将不会运行，如果要运行，需要使用关键字：force_handlers：yes
[root@localhost project]# !vim
vim ceshi1.yml
---
- hosts: 192.168.190.134
force_handlers: yes 强制执行handlers
tasks:
- name: show the date
template:
src: template/date.j2
dest: /tmp
notify:
restart apache
- name: error task
command: ls /sdsdsds
handlers:
- name: restart apache
service:
name: httpd
state: restarted
TASK [error task] **************************************************************************************
fatal: [192.168.190.134]: FAILED! => {"changed": true, "cmd": ["ls", "/sdsdsds"], "delta": "0:00:00.003698", "end": "2020-09-08 09:36:44.778096", "msg": "non-zero return code", "rc": 2, "start": "2020-09-08 09:36:44.774398", "stderr": "ls: cannot access '/sdsdsds': No such file or directory", "stderr_lines": ["ls: cannot access '/sdsdsds': No such file or directory"], "stdout": "", "stdout_lines": []}
RUNNING HANDLER [restart apache] *********************************************************************** handlers成功执行。
changed: [192.168.190.134]
PLAY RECAP *********************************************************************************************
192.168.190.134 : ok=3 changed=2 unreachable=0 failed=1 skipped=0 rescued=0 ignored=0
指定任务失败条件
方法一： 使用failed_when关键字
vim ceshi1.yml
---
- hosts: 192.168.190.134
tasks:
- name: test
script: files/test.sh 脚本在执行时，就算脚本里有错误，最后也是执行ok或者changed
register: result
failed_when: "'No such file or directory' in result.stdout" 加上报错的条件。
成功报错。
TASK [test] ********************************************************************************************
fatal: [192.168.190.134]: FAILED! => {"changed": true, "failed_when_result": true, "rc": 0, "stderr": "Shared connection to 192.168.190.134 closed.\r\n", "stderr_lines": ["Shared connection to 192.168.190.134 closed."], "stdout": "ls: cannot access 'sdsdsdsdsdsds': No such file or directory\r\nanaconda-ks.cfg\r\n", "stdout_lines": ["ls: cannot access 'sdsdsdsdsdsds': No such file or directory", "anaconda-ks.cfg"]}
方法二：使用fail模块进行报错条件
[root@localhost project]# !vim
vim ceshi1.yml
---
- hosts: 192.168.190.134
tasks:
- name: test
script: files/test.sh
register: result
- name: fail control
fail:
msg: "you are a fool" 明确错误提示。
when:
"'No such file or directory' in result.stdout"
TASK [fail control] ************************************************************************************
fatal: [192.168.190.134]: FAILED! => {"changed": false, "msg": "you are a fool"}
指定任务何时报告"Changed"结果
利用changed_when关键字来确定是否报告changed结果
[root@localhost project]# vim ceshi1.yml
---
- hosts: 192.168.190.134
tasks:
- name: useradd
user:
name: test1
state: present
changed_when: True 无论是否成功执行。报告返回结果都为changed.如果为False，在task没有错误的情况下，始终返回ok。
ansible 块和错误处理
三种关键字：
- block：定义要运行的主要任务
- rescue：定义要在 block 子句中定义的任务失败时运行的任务
- always：定义始终独立运行的任务
---
- hosts: 192.168.190.134
vars:
file_name: test1
tasks:
- name: test block
block:
- name: block1
command: ls /tmp
- name: block2
command: ls /tmp/{{ file_name }} 若文件不存在，执行rescue
rescue:
- name: touch the {{ file_name }} 创建此文件
file:
name: "{{ file_name }}"
state: touch
always: 无论block成功与否，都执行always
- name: print
command: echo "\(@^0^@)/"
register: result
- debug:
msg: " {{ result.stdout }} "
