如何在ansible中检测无法访问的目标主机

Question

如果目标主机all_hosts可访问或不可访问，我希望获取变量sshreachable。

我也写了下面的剧本。

- name: Play 3- check telnet nodes
hosts: localhost
ignore_unreachable: yes

- name: Check all port numbers are accessible from current host
include_tasks: innertelnet.yml
with_items: "{{ groups['all_hosts'] }}"

cat innertelnet.yml

---
- name: Check ssh connectivity
block:
- raw: "ssh -o BatchMode=yes root@{{ item }} echo success"
ignore_errors: yes
register: sshcheck
- debug:
msg: "SSHCHECK variable:{{ sshcheck }}"
- set_fact:
sshreachable: 'SSH SUCCESS'
when: sshcheck.unreachable == 'false'
- set_fact:
sshreachable: 'SSH FAILED'
when: sshcheck.unreachable == 'true'
- debug:
msg: "INNERSSH1: {{ sshreachable }}"

不幸的是，我得到如下错误：

输出：

TASK [raw] *********************************************************************
fatal: [localhost]: UNREACHABLE! => {"changed": false, "msg": "Failed to connect to the host via ssh: Shared connection to 10.9.9.126 closed.", "skip_reason": "Host localhost is unreachable", "unreachable": true}

TASK [debug] ***********************************************************************************************************************************************************
task path:
ok: [localhost] => {
"msg": "SSHCHECK variable:{'msg': u'Failed to connect to the host via ssh: Shared connection to 10.9.9.126 closed.', 'unreachable': True, 'changed': False}"
}
TASK [set_fact] ****************************************************************
skipping: [localhost]
TASK [set_fact] ****************************************************************
skipping: [localhost]
TASK [debug] *******************************************************************
fatal: [localhost]: FAILED! => {"msg": "The task includes an option with an undefined variable. The error was: 'sshreachable' is undefinednnThe error appears to be in '/app/playbook/checkssh/innertelnet.yml': line 45, column 10, but maynbe elsewhere in the file depending on the exact syntax problem.nnThe offending line appears to be:nnn       - debug:n         ^ heren"}
PLAY RECAP *********************************************************************
10.0.116.194                : ok=101  changed=1    unreachable=9    failed=0    skipped=12   rescued=0    ignored=95  
localhost          : ok=5    changed=0    unreachable=1    failed=1    skipped=4    rescued=0    ignored=0  

你能建议修改我的代码吗？

Answer 1

该错误似乎表明sshreachable变量未被设置，因为when:条件不匹配。即sshcheck.unreachable可能不是raw返回的东西。

为此，command模块应该足够了，我们可以评估命令对set_fact的返回代码。

你可以做一些类似的事情：

- block:
- command: ssh -o BatchMode=yes user@host1 echo success
ignore_errors: yes
register: sshcheck
- set_fact:
sshreachable: "{{ sshcheck is success }}"
- debug:
msg: "Host1 reachable: {{ sshreachable | string }}"

更新：

raw模块似乎以同样的方式工作。示例(包括@mdaniel的宝贵输入(：

- block:
- raw: ssh -o BatchMode=yes user@host1 echo success
ignore_errors: yes
register: sshcheck
- set_fact:
sshreachable: SSH SUCCESS
when: sshcheck is success
- set_fact:
sshreachable: SSH FAILED
when: sshcheck is failed
- debug:
msg: "Host1 reachable: {{ sshreachable }}"