一、Ansible处理任务失败
1、管理play中任务错误
1️⃣：Ansible评估任务的返回代码，从而确定任务是成功还是失败
2️⃣：通常而言，当任务失败时，Ansible将立即在该主机上中止play的其余部分并且跳过所有后续任务，但有些时候，可能希望即使在任务失败时也继续执行play
2、忽略任务失败
1️⃣：默认情况下，任务失败时play会中止。不过，可以通过忽略失败的任务来覆盖此行为。可以在任务中使用ignore_errors关键字来实现此目的
- 演示实例：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 //查看playbook[root@localhost project]# cat playbook.yaml---- hosts: allgather_facts: notasks:- name:installhttpdyum:name: packages//没有这个包state: presentignore_errors:yes//可选｛yes、no｝- name: shoe some massagedebug:msg:"hello word"//执行play[root@localhost project]# ansible-playbook playbook.yamlPLAY [all] ****************************************************************************************************************************************************************TASK [installhttpd] ******************************************************************************************************************************************************fatal: [client.example.com]: FAILED! => {"ansible_facts": {"discovered_interpreter_python":"/usr/libexec/platform-python"},"changed":false,"failures": ["No package packages available."],"msg":"Failed to install some of the specified packages","rc": 1,"results": []}...ignoring//已经忽略这个任务出错TASK [shoe some massage] **************************************************************************************************************************************************ok: [client.example.com] => {"msg":"hello word"}PLAY RECAP ****************************************************************************************************************************************************************client.example.com : ok=2 changed=0 unreachable=0 failed=0 skipped=0 rescued=0 ignored=1
3、任务失败也强制执行处理程序（handlers）
1️⃣：在play中设置force_handlers: yes关键字，则即使play因为后续任务失败而中止也会调用被通知的处理程序（force：促使，推动）
- 演示实例：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 //查看playbook[root@localhost project]# cat playbook.yaml---- hosts: allforce_handlers:yes//可选｛yes、no｝tasks:- name:installhttpdshell:ls//这条命令一定会执行成功，从而保证handlers处理程序一定会被触发notify:- massage- name:installhttpdyum:name: packages//没有这个包，肯定会出错state: presenthandlers:- name: massagedebug:msg:"hello word"//执行play[root@localhost project]# ansible-playbook playbook.yamlPLAY [all] ****************************************************************************************************************************************************************TASK [Gathering Facts] ****************************************************************************************************************************************************ok: [client.example.com]TASK [installhttpd] ******************************************************************************************************************************************************changed: [client.example.com]TASK [installhttpd] *****************************************************************************************************************************************************fatal: [client.example.com]: FAILED! => {"changed":false,"failures": ["No package packages available."],"msg":"Failed to install some of the specified packages","rc": 1,"results": []}RUNNING HANDLER [massage] *************************************************************************************************************************************************ok: [client.example.com] => {"msg":"hello word"}PLAY RECAP ****************************************************************************************************************************************************************client.example.com : ok=3 changed=1 unreachable=0 failed=1 skipped=0 rescued=0 ignored=0
2️⃣：处理程序会在任务报告changed结果时获得通知，而在任务报告ok或failed结果时不会获得通知
4、指定任务失败的条件
1️⃣：在任务中使用failed_when关键字来指定表示任务已失败的条件；通常与命令模块搭配使用，这些模块可能成功执行了某一命令，但命令的输出可能指示了失败
- 演示实例一：使用failed_when关键字
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 //查看使用的脚本[root@localhost project]# cat files/test.sh#!/bin/bashcat/root//这句肯定会出错echo"hello word"//注意：在playbook中执行脚本会以最后一个命令作为错误判断标准，中间错误命令不会影响整体的出错，同样也不会因为中间出错而报错//查看playbook，执行一次看是否成功[root@localhost project]# cat playbook.yaml---- hosts: alltasks:- name:testscript:files/test.sh[root@localhost project]# ansible-playbook playbook.yamlPLAY [all] ****************************************************************************************************************************************************************TASK [Gathering Facts] ****************************************************************************************************************************************************ok: [client.example.com]TASK [test] ***************************************************************************************************************************************************************changed: [client.example.com]PLAY RECAP ****************************************************************************************************************************************************************client.example.com : ok=2 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0//这样无法判断是否都执行成功//添加任务失败判断语句[root@localhost project]# cat playbook.yaml---- hosts: alltasks:- name:testscript:files/test.shregister: resultfailed_when:"'Is a directory' in result['stdout']"[root@localhost project]# ansible-playbook playbook.yamlPLAY [all] ****************************************************************************************************************************************************************TASK [Gathering Facts] ****************************************************************************************************************************************************ok: [client.example.com]TASK [test] ***************************************************************************************************************************************************************fatal: [client.example.com]: FAILED! => {"changed":true,"failed_when_result":true,"rc": 0,"stderr":"Shared connection to client.example.com closed.\r\n","stderr_lines": ["Shared connection to client.example.com closed."],"stdout":"cat: /root: Is a directory\r\nhello word\r\n","stdout_lines": ["cat: /root: Is a directory","hello word"]}PLAY RECAP ****************************************************************************************************************************************************************client.example.com : ok=1 changed=0 unreachable=0 failed=1 skipped=0 rescued=0 ignored=0
2️⃣：fail模块也可用于强制任务失败（主要是将杂乱的提示信息通过自己设置提示方式，达到简单、明了的目的）
- 演示实例二：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 //查看playbook[root@localhost project]# cat playbook.yaml---- hosts: alltasks:- name:testscript:files/test.shregister: result- fail:msg:"There have a failed"when:"'Is a directory' in result['stdout']"//执行play[root@localhost project]# ansible-playbook playbook.yamlPLAY [all] ****************************************************************************************************************************************************************TASK [Gathering Facts] ****************************************************************************************************************************************************ok: [client.example.com]TASK [test] ***************************************************************************************************************************************************************changed: [client.example.com]TASK [fail] ***************************************************************************************************************************************************************fatal: [client.example.com]: FAILED! => {"changed":false,"msg":"There have a failed"}PLAY RECAP ****************************************************************************************************************************************************************client.example.com : ok=2 changed=1 unreachable=0 failed=1 skipped=0 rescued=0 ignored=0
5、指定何时任务报告“changed”结果
1️⃣：当任务对托管主机进行了更改时，会报告 changed 状态并通知处理程序；如果任务不需要进行更改，则会报告ok并且不通知处理程序
2️⃣：使用changed_when关键字可用于控制任务在何时报告它已进行了更改
- 演示实例一：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 //查看playbook[root@localhost project]# cat playbook.yaml---- hosts: alltasks:- name:testshell:echo"hello word"//执行后发现，每次都是changed[root@localhost project]# ansible-playbook playbook.yamlPLAY [all] ****************************************************************************************************************************************************************TASK [Gathering Facts] ****************************************************************************************************************************************************ok: [client.example.com]TASK [test] ***************************************************************************************************************************************************************changed: [client.example.com]PLAY RECAP ****************************************************************************************************************************************************************client.example.com : ok=2 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0//添加changed_when关键字，以便报告OK[root@localhost project]# cat playbook.yaml---- hosts: alltasks:- name:testshell:echo"hello word"changed_when:false//可选｛true、false｝[root@localhost project]# ansible-playbook playbook.yamlPLAY [all] ****************************************************************************************************************************************************************TASK [Gathering Facts] ****************************************************************************************************************************************************ok: [client.example.com]TASK [test] ***************************************************************************************************************************************************************ok: [client.example.com]PLAY RECAP ****************************************************************************************************************************************************************client.example.com : ok=2 changed=0 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
3️⃣：根据通过已注册变量收集的模块的输出来报告changed
- 演示实例二：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 //查看playbook[root@localhost project]# cat playbook.yaml---- hosts: alltasks:- name:testcommand:echo"hello word"register: resultchanged_when:"'hello word' in result['stdout']"//执行play[root@localhost project]# ansible-playbook playbook.yamlPLAY [all] ****************************************************************************************************************************************************************TASK [Gathering Facts] ****************************************************************************************************************************************************ok: [client.example.com]TASK [test] ***************************************************************************************************************************************************************changed: [client.example.com]PLAY RECAP ****************************************************************************************************************************************************************client.example.com : ok=2 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0//因为在result['stdout']中有hello word ，所以被认定为是true，所以就显示changed
6、Ansible块和错误处理
1️⃣：在playbook中，块是对任务进行逻辑分组的子句，可用于控制任务的执行方式
2️⃣：通过块，也可结合rescue和always语句来处理错误。如果块中的任何任务失败，则执行其rescue块中的任务来进行恢复
3️⃣：在block子句中的任务以及rescue子句中的任务（如果出现故障）运行之后，always子句中的任务运行
4️⃣：总结：
- 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：定义始终都独立运行的任务，不论block和rescue子句中定义的任务是成功还是失败
5️⃣：演示：
- 演示实例一：当只有block和rescue，且block语句执行成功时，只执行block语句而不执行rescue语句（rescue：营救、救援）
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 //查看playbook[root@localhost project]# cat playbook.yaml---- hosts: allgather_facts: notasks:- name:testblock:- name: blockshell:echo"hello word"rescue:- name: rescueshell:ls/root//执行play[root@localhost project]# ansible-playbook --syntax-check playbook.yamlplaybook: playbook.yaml[root@localhost project]# ananacron ansible-config ansible-console ansible-galaxy ansible-playbook ansible-testansible ansible-connection ansible-doc ansible-inventory ansible-pull ansible-vault[root@localhost project]# ansible-playbook playbook.yamlPLAY [all] ****************************************************************************************************************************************************************TASK [block] **************************************************************************************************************************************************************changed: [client.example.com]PLAY RECAP ****************************************************************************************************************************************************************client.example.com : ok=1 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0//可以发现，只执行了block语句，并没有执行rescue语句
- 演示实例二：当只有block和rescue，且block语句执行失败时，不执行block语句而执行rescue语句
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 //查看playbook[root@localhost project]# cat playbook.yaml---- hosts: allgather_facts: notasks:- name:testblock:- name: blockcommand:cat///这句肯定会失败rescue:- name: rescueshell:ls/root//执行play[root@localhost project]# ansible-playbook playbook.yamlPLAY [all] ****************************************************************************************************************************************************************TASK [block] **************************************************************************************************************************************************************fatal: [client.example.com]: FAILED! => {"ansible_facts": {"discovered_interpreter_python":"/usr/libexec/platform-python"},"changed":true,"cmd": ["cat","/"],"delta":"0:00:00.005350","end":"2020-09-08 10:59:18.381699","msg":"non-zero return code","rc": 1,"start":"2020-09-08 10:59:18.376349","stderr":"cat: /: Is a directory","stderr_lines": ["cat: /: Is a directory"],"stdout":"","stdout_lines": []}TASK [rescue] *************************************************************************************************************************************************************changed: [client.example.com]PLAY RECAP ****************************************************************************************************************************************************************client.example.com : ok=1 changed=1 unreachable=0 failed=0 skipped=0 rescued=1 ignored=0//可以看出，block语句执行失败而执行了rescue语句
- 演示实例三：当block语句、rescue语句和always语句都有时，无论block语句是否失败，always语句总是执行
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 //查看playbook[root@localhost project]# cat playbook.yaml---- hosts: allgather_facts: notasks:- name:testblock:- name: blockcommand:cat/rescue:- name: rescueshell:ls/rootalways:- name: alwaysdebug:msg:"This is my test"//执行play[root@localhost project]# ansible-playbook playbook.yamlPLAY [all] ****************************************************************************************************************************************************************TASK [block] **************************************************************************************************************************************************************fatal: [client.example.com]: FAILED! => {"ansible_facts": {"discovered_interpreter_python":"/usr/libexec/platform-python"},"changed":true,"cmd": ["cat","/"],"delta":"0:00:00.008993","end":"2020-09-08 11:05:47.816489","msg":"non-zero return code","rc": 1,"start":"2020-09-08 11:05:47.807496","stderr":"cat: /: Is a directory","stderr_lines": ["cat: /: Is a directory"],"stdout":"","stdout_lines": []}TASK [rescue] *************************************************************************************************************************************************************changed: [client.example.com]TASK [always] *************************************************************************************************************************************************************ok: [client.example.com] => {"msg":"This is my test"}PLAY RECAP ****************************************************************************************************************************************************************client.example.com : ok=2 changed=1 unreachable=0 failed=0 skipped=0 rescued=1 ignored=0
6️⃣：block中的when条件也会应用到其rescue和always子句（若存在）
- 演示实例一：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 //查看playbook[root@localhost project]# cat playbook.yaml---- hosts: allgather_facts: notasks:- name:testblock:- name: blockcommand:echo"hello word"//该语句没有错误when: ansible_facts['distribution'] =="CentOS"//条件判断出错会导致block语句不会执行rescue:- name: rescueshell:ls/rootalways:- name: alwaysdebug:msg:"This is my test"//执行play[root@localhost project]# ansible-playbook playbook.yamlPLAY [all] ****************************************************************************************************************************************************************TASK [block] **************************************************************************************************************************************************************fatal: [client.example.com]: FAILED! => {"msg":"The conditional check 'ansible_facts['distribution'] == \"CentOS\"' failed. The error was: error while evaluating conditional (ansible_facts['distribution'] == \"CentOS\"): 'dict object' has no attribute 'distribution'\n\nThe error appears to be in '/root/project/playbook.yaml': line 7, column 11, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n block:\n - name: block\n ^ here\n"}TASK [rescue] *************************************************************************************************************************************************************changed: [client.example.com]TASK [always] *************************************************************************************************************************************************************ok: [client.example.com] => {"msg":"This is my test"}PLAY RECAP ****************************************************************************************************************************************************************client.example.com : ok=2 changed=1 unreachable=0 failed=0 skipped=0 rescued=1 ignored=0
- 演示实例二：
//查看playbook [root@localhost project]# cat playbook.yaml --- - hosts: all gather_facts: no tasks: - name: test block: - name: block command: echo "hello word" when: ansible_facts['distribution'] == "CentOS" rescue: - name: rescue shell: ls /root when: ansible_facts['distribution_major_version'] == "7" //这句when语句会执行失败，导致rescue语句不会执行 always: - name: always debug: msg: "This is my test" //执行play [root@localhost project]# ansible-playbook playbook.yaml PLAY [all] **************************************************************************************************************************************************************** TASK [block] ************************************************************************************************************************************************************** fatal: [client.example.com]: FAILED! => {"msg": "The conditional check 'ansible_facts['distribution'] == \"CentOS\"' failed. The error was: error while evaluating conditional (ansible_facts['distribution'] == \"CentOS\"): 'dict object' has no attribute 'distribution'\n\nThe error appears to be in '/root/project/playbook.yaml': line 7, column 11, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n block:\n - name: block\n ^ here\n"} TASK [rescue] ************************************************************************************************************************************************************* fatal: [client.example.com]: FAILED! => {"msg": "The conditional check 'ansible_facts['distribution_major_version'] == \"7\"' failed. The error was: error while evaluating conditional (ansible_facts['distribution_major_version'] == \"7\"): 'dict object' has no attribute 'distribution_major_version'\n\nThe error appears to be in '/root/project/playbook.yaml': line 12, column 11, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n rescue:\n - name: rescue\n ^ here\n"} TASK [always] ************************************************************************************************************************************************************* ok: [client.example.com] => { "msg": "This is my test" } PLAY RECAP **************************************************************************************************************************************************************** client.example.com : ok=1 changed=0 unreachable=0 failed=1 skipped=0 rescued=1 ignored=0 //可以看出，block语句和rescue语句都没执行
- 演示实例三：
//查看playbook [root@localhost project]# cat playbook.yaml --- - hosts: all gather_facts: no tasks: - name: test block: - name: block command: echo "hello word" rescue: - name: rescue shell: ls /root always: - name: always debug: msg: "This is my test" when: ansible_facts['distribution_version'] == "8" //when条件储出错没回导致always语句执行失败 //执行play [root@localhost project]# ansible-playbook playbook.yaml PLAY [all] **************************************************************************************************************************************************************** TASK [block] ************************************************************************************************************************************************************** changed: [client.example.com] TASK [always] ************************************************************************************************************************************************************* fatal: [client.example.com]: FAILED! => {"msg": "The conditional check 'ansible_facts['distribution_version'] == \"8\"' failed. The error was: error while evaluating conditional (ansible_facts['distribution_version'] == \"8\"): 'dict object' has no attribute 'distribution_version'\n\nThe error appears to be in '/root/project/playbook.yaml': line 15, column 11, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n always:\n - name: always\n ^ here\n"} PLAY RECAP **************************************************************************************************************************************************************** client.example.com : ok=1 changed=1 unreachable=0 failed=1 skipped=0 rescued=0 ignored=0
- 注意：block执行会成功的话，如果用when条件判断，即使判断条件会成功，但block语句任然会失败，而去执行rescue语句
转自
Ansible_处理失败的任务 - 珍朱奶茶 - 博客园
https://www.cnblogs.com/itwangqiang/p/13629677.html