ansible笔记（18）：变量（五）

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发布时间：May 25, 2021
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Categories： Ansible

<blockquote>在本博客中，ansible是一个系列文章，我们会尽量以通俗易懂的方式总结ansible的相关知识点。

ansible系列博文直达链接：<a href="https://www.zsythink.net/archives/tag/ansible/" target="_blank" rel="noopener">ansible轻松入门系列</a>

“ansible系列”中的每篇文章都建立在前文的基础之上，所以，请按照顺序阅读这些文章，否则有可能在阅读中遇到障碍。</blockquote>
ansible中还有一些内置变量可供我们使用，当然，这些内置变量的变量名是被ansible保留的，我们定义变量时不能使用这些变量名。

&nbsp;

&nbsp;
<h2 id="wznav_0">内置变量ansible_version</h2>
先从一个简单的内置变量说起，比如，我们可以通过内置变量ansible_version获取到ansible的版本号，示例命令如下
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<div><span class="enlighter-text">ansible test70 -m debug -a </span><span class="enlighter-s0">"msg={{ansible_version}}"</span></div>
</div>
</div>
</div>
&nbsp;

&nbsp;
<h2 id="wznav_1">内置变量hostvars</h2>
除了ansible_version，还有一些非常有用的内置变量。比如内置变量hostvars

hostvars可以帮助我们在操作当前主机时获取到其他主机中的信息。

假设，我想要在操作test70主机时获取到test71主机中的facts信息，我该怎么办呢？示例如下
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<div><span class="enlighter-text">---</span></div>
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<div><span class="enlighter-text">- name: </span><span class="enlighter-s0">"play 1: Gather facts of test71"</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> hosts: test71</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> remote_user: root</span></div>
</div>
<div class="">
<div></div>
</div>
<div class="">
<div><span class="enlighter-text">- name: </span><span class="enlighter-s0">"play 2: Get facts of test71 when operating on test70"</span></div>
</div>
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<div><span class="enlighter-text"> hosts: test70</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> remote_user: root</span></div>
</div>
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<div><span class="enlighter-text"> tasks:</span></div>
</div>
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<div><span class="enlighter-text"> - debug:</span></div>
</div>
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<div><span class="enlighter-text"> msg: </span><span class="enlighter-s0">"{{hostvars['test71'].ansible_ens35.ipv4}}"</span></div>
</div>
</div>
</div>
上例中有两个play，第一个play针对test71主机执行，但是第一个play中没有显式指定任何task（后文会解释原因），第二个play针对test70主机执行，在第二个play中只有一个task，即使用debug模块，输出了test71主机中的ens35网卡的IP信息，如你所见，我们可以借助hostvars在操作当前主机时输出其他主机中的facts信息，上例中使用hostvars加上清单中的主机名称再加上facts的key，即可获取到对应的facts信息，有了前文的总结作为基础，你一定想到了，上例中的msg的值改为如下写法也是可以的。
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<div><span class="enlighter-s0">"{{hostvars.test71.ansible_ens35.ipv4}}"</span></div>
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&nbsp;

上例中的第一个play中并没有任何的task，为什么还需要第一个play呢？如果你将上例的第一个play删除，只保留第二个play，运行时则会报错，这是因为，虽然第一个play中没有任何task，但是当第一个play执行时，默认会调用”[Gathering Facts]”任务，也就是说，默认会收集test71主机的facts信息，只有被收集过的facts信息才能被后面的play引用到，如果压根没有收集对应主机的facts信息，即使使用hostvars内置变量，也无法获取到对应主机的facts信息，我们来做个试验，我们可以直接把上例的第一个play从playbook中删除，也可以指明让第一个play不收集对应的facts信息，使用”gather_facts”关键字可以控制当前play是否收集对应主机的facts信息，示例如下:
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<div><span class="enlighter-text">---</span></div>
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<div><span class="enlighter-text">- name: </span><span class="enlighter-s0">"play 1: Gather facts of test71"</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> hosts: test71</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> remote_user: root</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> gather_facts: no</span></div>
</div>
<div class="">
<div></div>
</div>
<div class="">
<div><span class="enlighter-text">- name: </span><span class="enlighter-s0">"play 2: Get facts of test71 when operating on test70"</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> hosts: test70</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> remote_user: root</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> tasks:</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> - debug:</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> msg: </span><span class="enlighter-s0">"{{hostvars['test71'].ansible_ens35.ipv4}}"</span></div>
</div>
</div>
</div>
如上例所示，第一个play中的”gather_facts: no”表示设置当前play不收集对应主机的信息，运行上例playbook会报错，因为第二个play在操作test70时，无法获取到test71主机中的facts信息，原因是test71的facts信息并未被收集过，所以，调用其他主机的facts信息的前提是对应主机的facts信息已经被收集过。

&nbsp;

其实，除了facts信息，我们还能够利用hostvars内置变量从别的主机中获取到其他类型的一些变量信息，比如，其他主机的注册变量、主机变量、组变量等信息，我们先来看一个获取其他主机的注册变量的小示例，如下：
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<div><span class="enlighter-text">---</span></div>
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<div class="">
<div><span class="enlighter-text">- hosts: test71</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> remote_user: root</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> gather_facts: no</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> tasks:</span></div>
</div>
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<div><span class="enlighter-text"> - shell: </span><span class="enlighter-s0">"echo register_var_in_play1"</span></div>
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<div><span class="enlighter-text"> register: shellreturn</span></div>
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<div></div>
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<div class="">
<div><span class="enlighter-text">- hosts: test70</span></div>
</div>
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<div><span class="enlighter-text"> remote_user: root</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> gather_facts: no</span></div>
</div>
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<div><span class="enlighter-text"> tasks:</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> - debug:</span></div>
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<div><span class="enlighter-text"> msg: </span><span class="enlighter-s0">"{{hostvars.test71.shellreturn.stdout}}"</span></div>
</div>
</div>
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如上例所示，通过hostvars内置变量可以直接获取到其他主机中的注册变量，你一定发现了，注册变量并不用像facts信息那样需要事先收集，即可直接通过hostvars跨主机被引用到，同理，如果你在清单中为test71主机配置了主机变量，或者为test71主机所在的组配置了组变量，也是可以通过hostvars直接跨主机引用的，这里就不进行示例了，动手试试吧。

&nbsp;

你可能会问，如果我直接在play中为当前主机定义一个变量，可以在之后的play中操作其他主机时被引用到吗？那么我们来做个实验，示例如下
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<div><span class="enlighter-text">---</span></div>
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<div class="">
<div><span class="enlighter-text">- hosts: test71</span></div>
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<div class="">
<div><span class="enlighter-text"> remote_user: root</span></div>
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<div class="">
<div><span class="enlighter-text"> gather_facts: no</span></div>
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<div><span class="enlighter-text"> vars:</span></div>
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<div><span class="enlighter-text"> testvar: testvar_in_71</span></div>
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<div><span class="enlighter-text"> tasks:</span></div>
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<div><span class="enlighter-text"> - debug:</span></div>
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<div class="">
<div><span class="enlighter-text"> msg: </span><span class="enlighter-s0">"{{testvar}}"</span></div>
</div>
<div class="">
<div></div>
</div>
<div class="">
<div><span class="enlighter-text">- hosts: test70</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> remote_user: root</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> gather_facts: no</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> tasks:</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> - debug:</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> msg: </span><span class="enlighter-s0">"{{hostvars.test71.testvar}}"</span></div>
</div>
</div>
</div>
在上例的第一个play中我们为test71主机定义了一个变量，变量名称为testvar，在第二个play中操作test70主机时，使用hostvars尝试引用test71主机中的变量，如果执行上述playbook则会报错，看来通过vars关键字定义的变量使用上例中的方法是无法被跨主机引用的，聪明如你，一定想到了解决方案，前一篇文章中，我们总结了怎样使用”set_fact”关键字定义变量，通过”set_fact”关键字定义的变量拥有类似”facts”信息的特性（如果不明白可以参考前文），所以，我们可以把”vars”关键字中定义的变量通过”set_fact”关键字去定义，这样这些变量就好像facts信息被收集过一样，能被之后的play引用到了，示例如下
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<div><span class="enlighter-text">---</span></div>
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<div class="">
<div><span class="enlighter-text">- hosts: test71</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> remote_user: root</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> gather_facts: no</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> tasks:</span></div>
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<div><span class="enlighter-text"> - set_fact:</span></div>
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<div><span class="enlighter-text"> testvar: </span><span class="enlighter-s0">"testvar_in_71"</span></div>
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<div><span class="enlighter-text"> - debug:</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> msg: </span><span class="enlighter-s0">"{{testvar}}"</span></div>
</div>
<div class="">
<div></div>
</div>
<div class="">
<div><span class="enlighter-text">- hosts: test70</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> remote_user: root</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> gather_facts: no</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> tasks:</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> - debug:</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> msg: </span><span class="enlighter-s0">"{{hostvars.test71.testvar}}"</span></div>
</div>
</div>
</div>
上例通过”set_fact”结合”hostvars”的方式，实现了跨play获取其他主机中的变量信息的功能，还是很方便的。

&nbsp;

&nbsp;
<h2 id="wznav_2">内置变量inventory_hostname</h2>
通过inventory_hostname变量可以获取到被操作的当前主机的主机名称，这里所说的主机名称并不是linux系统的主机名，而是对应主机在清单中配置的名称，假设我的清单配置如下
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<div><span class="enlighter-g1">[</span><span class="enlighter-text">test_group</span><span class="enlighter-g1">]</span></div>
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<div><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.60</span></div>
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<div><span class="enlighter-text">test70.</span><span class="enlighter-m3">zsythink</span><span class="enlighter-text">.</span><span class="enlighter-m3">net</span><span class="enlighter-text"> ansible_host=</span><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.70</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test71 anisble_host=</span><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.71</span></div>
</div>
</div>
</div>
清单中配置了三个主机，第一个主机以IP的形式配置，第二个主机和第三个主机都以别名的方式配置，他们同属于test_group组。

那么我们使用内置变量inventory_hostname获取一下各个主机的对应的主机名，看看会返回什么，示例如下
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<div><span class="enlighter-c0"># ansible test_group -m debug -a "msg={{inventory_hostname}}"</span></div>
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<div><span class="enlighter-text">test70.</span><span class="enlighter-m3">zsythink</span><span class="enlighter-text">.</span><span class="enlighter-m3">net</span> <span class="enlighter-g0">|</span><span class="enlighter-text"> SUCCESS =</span><span class="enlighter-g1">&gt;</span> <span class="enlighter-g1">{</span></div>
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<div><span class="enlighter-s0">"changed"</span><span class="enlighter-text">: </span><span class="enlighter-k1">false</span><span class="enlighter-text">, </span></div>
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<div class="">
<div><span class="enlighter-s0">"msg"</span><span class="enlighter-text">: </span><span class="enlighter-s0">"test70.zsythink.net"</span></div>
</div>
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<div><span class="enlighter-g1">}</span></div>
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<div><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.60</span> <span class="enlighter-g0">|</span><span class="enlighter-text"> SUCCESS =</span><span class="enlighter-g1">&gt;</span> <span class="enlighter-g1">{</span></div>
</div>
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<div><span class="enlighter-s0">"changed"</span><span class="enlighter-text">: </span><span class="enlighter-k1">false</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"msg"</span><span class="enlighter-text">: </span><span class="enlighter-s0">"10.1.1.60"</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">}</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test71 </span><span class="enlighter-g0">|</span><span class="enlighter-text"> SUCCESS =</span><span class="enlighter-g1">&gt;</span> <span class="enlighter-g1">{</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"changed"</span><span class="enlighter-text">: </span><span class="enlighter-k1">false</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"msg"</span><span class="enlighter-text">: </span><span class="enlighter-s0">"test71"</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">}</span></div>
</div>
</div>
</div>
从返回信息可以看出，如果使用IP配置主机，inventory_hostname的值就是IP，如果使用别名，inventory_hostname的值就是别名。

&nbsp;

&nbsp;
<h2 id="wznav_3">内置变量inventory_hostname_short</h2>
与内置变量inventory_hostname类似，通过inventory_hostname_short也可以获取当前play操作的主机在清单中对应的名称，但是这个名称更加简短，假设我的清单配置如下
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<div class="">
<div><span class="enlighter-g1">[</span><span class="enlighter-text">test_group</span><span class="enlighter-g1">]</span></div>
</div>
<div class="">
<div><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.60</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test70.</span><span class="enlighter-m3">zsythink</span><span class="enlighter-text">.</span><span class="enlighter-m3">net</span><span class="enlighter-text"> ansible_host=</span><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.70</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test71 anisble_host=</span><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.71</span></div>
</div>
</div>
</div>
那么通过内置变量inventory_hostname_short获取到的主机的简短名称如下：
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<div><span class="enlighter-c0"># ansible test_group -m debug -a "msg={{inventory_hostname_short}}"</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test70.</span><span class="enlighter-m3">zsythink</span><span class="enlighter-text">.</span><span class="enlighter-m3">net</span> <span class="enlighter-g0">|</span><span class="enlighter-text"> SUCCESS =</span><span class="enlighter-g1">&gt;</span> <span class="enlighter-g1">{</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"changed"</span><span class="enlighter-text">: </span><span class="enlighter-k1">false</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"msg"</span><span class="enlighter-text">: </span><span class="enlighter-s0">"test70"</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">}</span></div>
</div>
<div class="">
<div><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.60</span> <span class="enlighter-g0">|</span><span class="enlighter-text"> SUCCESS =</span><span class="enlighter-g1">&gt;</span> <span class="enlighter-g1">{</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"changed"</span><span class="enlighter-text">: </span><span class="enlighter-k1">false</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"msg"</span><span class="enlighter-text">: </span><span class="enlighter-s0">"10"</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">}</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test71 </span><span class="enlighter-g0">|</span><span class="enlighter-text"> SUCCESS =</span><span class="enlighter-g1">&gt;</span> <span class="enlighter-g1">{</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"changed"</span><span class="enlighter-text">: </span><span class="enlighter-k1">false</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"msg"</span><span class="enlighter-text">: </span><span class="enlighter-s0">"test71"</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">}</span></div>
</div>
</div>
</div>
可以看到，无论是IP还是别名，如果清单的主机名称中包含”.”，inventory_hostname_short都会取得主机名中第一个”.”之前的字符作为主机的简短名称。

&nbsp;

&nbsp;
<h2 id="wznav_4">内置变量play_hosts</h2>
通过内置变量play_hosts可以获取到当前play所操作的所有主机的主机名列表，示例playbook如下：
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<div class="enlighter">
<div class="">
<div><span class="enlighter-text">---</span></div>
</div>
<div class="">
<div><span class="enlighter-text">- hosts: test70,test71</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> remote_user: root</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> gather_facts: no</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> tasks:</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> - debug:</span></div>
</div>
<div class="">
<div><span class="enlighter-text"> msg: </span><span class="enlighter-s0">"{{play_hosts}}"</span></div>
</div>
</div>
</div>
执行上例的playbook，返回信息如下
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<div class="">
<div><span class="enlighter-text">TASK </span><span class="enlighter-g1">[</span><span class="enlighter-text">debug</span><span class="enlighter-g1">]</span> <span class="enlighter-g0">*************************</span></div>
</div>
<div class="">
<div><span class="enlighter-text">ok: </span><span class="enlighter-g1">[</span><span class="enlighter-text">test70</span><span class="enlighter-g1">]</span><span class="enlighter-text"> =</span><span class="enlighter-g1">&gt;</span> <span class="enlighter-g1">{</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"msg"</span><span class="enlighter-text">: </span><span class="enlighter-g1">[</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test71"</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test70"</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">]</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">}</span></div>
</div>
<div class="">
<div><span class="enlighter-text">ok: </span><span class="enlighter-g1">[</span><span class="enlighter-text">test71</span><span class="enlighter-g1">]</span><span class="enlighter-text"> =</span><span class="enlighter-g1">&gt;</span> <span class="enlighter-g1">{</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"msg"</span><span class="enlighter-text">: </span><span class="enlighter-g1">[</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test71"</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test70"</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">]</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">}</span></div>
</div>
</div>
</div>
可以看到，此play每操作一个主机，都会将当前play操作的所有主机的主机名列表返回。

没错，inventory_hostname和play_hosts都是返回主机名，只不过，inventory_hostname只返回当前被操作的主机的主机名，而play_hosts则返回当前play中所有被操作主机的主机名列表。

&nbsp;

&nbsp;
<h2 id="wznav_5">内置变量groups</h2>
通过groups内置变量可以获取到清单中”所有分组”的”分组信息”，什么意思呢？我们先来看一个清单配置，假设我的清单配置如下：
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<div class="enlighter-btn enlighter-btn-raw"></div>
<div class="enlighter-btn enlighter-btn-copy"></div>
<div class="enlighter-btn enlighter-btn-window"></div>
</div>
<div class="enlighter">
<div class="">
<div><span class="enlighter-text">10.</span><span class="enlighter-m3">1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.60</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test70.</span><span class="enlighter-m3">zsythink</span><span class="enlighter-text">.</span><span class="enlighter-m3">net</span><span class="enlighter-text"> ansible_host=</span><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.70</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test71 anisble_host=</span><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.71</span></div>
</div>
<div class="">
<div></div>
</div>
<div class="">
<div><span class="enlighter-g1">[</span><span class="enlighter-text">testA</span><span class="enlighter-g1">]</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test60 ansible_host=</span><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.60</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test61 ansible_host=</span><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.61</span></div>
</div>
<div class="">
<div></div>
</div>
<div class="">
<div><span class="enlighter-g1">[</span><span class="enlighter-text">testB</span><span class="enlighter-g1">]</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test70 ansible_host=</span><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.70</span></div>
</div>
<div class="">
<div></div>
</div>
<div class="">
<div><span class="enlighter-g1">[</span><span class="enlighter-text">test:children</span><span class="enlighter-g1">]</span></div>
</div>
<div class="">
<div><span class="enlighter-text">testA</span></div>
</div>
<div class="">
<div><span class="enlighter-text">testB</span></div>
</div>
</div>
</div>
上述清单中，显式的指定了三个组，testA组、testB组、test组，其中，testA组与testB组是test组的子组，除了组中的主机，还有三台主机没有任何分组，直接写在了清单中。

&nbsp;

现在，我们获取一下groups变量的值，看看会返回哪些信息，随便操作清单中的任意一台主机即可，示例如下
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<div class="enlighter">
<div class="">
<div><span class="enlighter-c0"># ansible test70 -m debug -a "msg={{groups}}"</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test70 </span><span class="enlighter-g0">|</span><span class="enlighter-text"> SUCCESS =</span><span class="enlighter-g1">&gt;</span> <span class="enlighter-g1">{</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"changed"</span><span class="enlighter-text">: </span><span class="enlighter-k1">false</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"msg"</span><span class="enlighter-text">: </span><span class="enlighter-g1">{</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"all"</span><span class="enlighter-text">: </span><span class="enlighter-g1">[</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"10.1.1.60"</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test70.zsythink.net"</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test71"</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test60"</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test61"</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test70"</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">]</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test"</span><span class="enlighter-text">: </span><span class="enlighter-g1">[</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test60"</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test61"</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test70"</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">]</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"testA"</span><span class="enlighter-text">: </span><span class="enlighter-g1">[</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test60"</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test61"</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">]</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"testB"</span><span class="enlighter-text">: </span><span class="enlighter-g1">[</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test70"</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">]</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"ungrouped"</span><span class="enlighter-text">: </span><span class="enlighter-g1">[</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"10.1.1.60"</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test70.zsythink.net"</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test71"</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">]</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">}</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">}</span></div>
</div>
</div>
</div>
从上述返回信息可以看出，所有主机默认被分成了组名为”all”的组，testA组中有两台主机，testB组中有一台主机，由于testA组和testB组都属于test组的子组，所以testA组与testB组中的主机都属于test组，由于有三台主机在清单中并未分组，所以，ansible自动将没有分组的主机分到了名为”ungrouped”的组中，即组名为”未分组”的组。

&nbsp;

我们还能够通过组名，获取到指定组的分组信息，假设，我想要获取到上例中test组中的主机名称，则可以使用如下方法。
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<div class="enlighter-btn enlighter-btn-window"></div>
</div>
<div class="enlighter">
<div class="">
<div><span class="enlighter-c0"># ansible test70 -m debug -a "msg={{groups.test}}"</span></div>
</div>
</div>
</div>
当然，语法也可以改为如下
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<div class="enlighter-btn enlighter-btn-window"></div>
</div>
<div class="enlighter">
<div class="">
<div><span class="enlighter-c0"># ansible test70 -m debug -a "msg={{groups['test']}}"</span></div>
</div>
</div>
</div>
&nbsp;

聪明如你一定已经会举一反三了，所以，如果我们想要获取到所有未分组主机的主机名，则可以使用如下方法
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<div class="enlighter-btn enlighter-btn-raw"></div>
<div class="enlighter-btn enlighter-btn-copy"></div>
<div class="enlighter-btn enlighter-btn-window"></div>
</div>
<div class="enlighter">
<div class="">
<div><span class="enlighter-c0"># ansible test70 -m debug -a "msg={{groups.ungrouped}}"</span></div>
</div>
</div>
</div>
&nbsp;

&nbsp;
<h2 id="wznav_6">内置变量group_names</h2>
见名知义，我们可以通过内置变量group_names获取到当前主机所在分组的组名，比如，我的清单配置如下
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<div class="enlighter-toolbar">
<div class="enlighter-btn enlighter-btn-raw"></div>
<div class="enlighter-btn enlighter-btn-copy"></div>
<div class="enlighter-btn enlighter-btn-window"></div>
</div>
<div class="enlighter">
<div class="">
<div><span class="enlighter-text">10.</span><span class="enlighter-m3">1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.60</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test70.</span><span class="enlighter-m3">zsythink</span><span class="enlighter-text">.</span><span class="enlighter-m3">net</span><span class="enlighter-text"> ansible_host=</span><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.70</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test71 anisble_host=</span><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.71</span></div>
</div>
<div class="">
<div></div>
</div>
<div class="">
<div><span class="enlighter-g1">[</span><span class="enlighter-text">testA</span><span class="enlighter-g1">]</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test60 ansible_host=</span><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.60</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test61 ansible_host=</span><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.61</span></div>
</div>
<div class="">
<div></div>
</div>
<div class="">
<div><span class="enlighter-g1">[</span><span class="enlighter-text">testB</span><span class="enlighter-g1">]</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test70 ansible_host=</span><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.70</span></div>
</div>
<div class="">
<div></div>
</div>
<div class="">
<div><span class="enlighter-g1">[</span><span class="enlighter-text">test:children</span><span class="enlighter-g1">]</span></div>
</div>
<div class="">
<div><span class="enlighter-text">testA</span></div>
</div>
<div class="">
<div><span class="enlighter-text">testB</span></div>
</div>
</div>
</div>
那么，当我操作test70主机时，group_names变量值如下
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<div class="enlighter-btn enlighter-btn-raw"></div>
<div class="enlighter-btn enlighter-btn-copy"></div>
<div class="enlighter-btn enlighter-btn-window"></div>
</div>
<div class="enlighter">
<div class="">
<div><span class="enlighter-c0"># ansible test70 -m debug -a "msg={{group_names}}"</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test70 </span><span class="enlighter-g0">|</span><span class="enlighter-text"> SUCCESS =</span><span class="enlighter-g1">&gt;</span> <span class="enlighter-g1">{</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"changed"</span><span class="enlighter-text">: </span><span class="enlighter-k1">false</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"msg"</span><span class="enlighter-text">: </span><span class="enlighter-g1">[</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"test"</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"testB"</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">]</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">}</span></div>
</div>
</div>
</div>
如上例返回值所示，test70主机属于testB组，而testB组又是test组的子组，所以test70主机同时属于testB组和test组，所以，最终返回的信息中包括test与testB

&nbsp;

当我们操作未分组的主机时，group_names的值为”ungrouped”，示例如下
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<div class="enlighter-toolbar">
<div class="enlighter-btn enlighter-btn-raw"></div>
<div class="enlighter-btn enlighter-btn-copy"></div>
<div class="enlighter-btn enlighter-btn-window"></div>
</div>
<div class="enlighter">
<div class="">
<div><span class="enlighter-c0"># ansible 10.1.1.60 -m debug -a "msg={{group_names}}"</span></div>
</div>
<div class="">
<div><span class="enlighter-n0">10.1</span><span class="enlighter-text">.</span><span class="enlighter-n0">1.60</span> <span class="enlighter-g0">|</span><span class="enlighter-text"> SUCCESS =</span><span class="enlighter-g1">&gt;</span> <span class="enlighter-g1">{</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"changed"</span><span class="enlighter-text">: </span><span class="enlighter-k1">false</span><span class="enlighter-text">,</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"msg"</span><span class="enlighter-text">: </span><span class="enlighter-g1">[</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"ungrouped"</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">]</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">}</span></div>
</div>
</div>
</div>
&nbsp;

&nbsp;
<h2 id="wznav_7">内置变量inventory_dir</h2>
我们可以通过inventory_dir变量获取到ansible主机中清单文件的存放路径，我使用的是默认的清单文件/etc/ansible/hosts，所以，inventory_dir变量对应的值为/etc/ansible，如下例所示
<div class="enlighter-default enlighter-v-standard enlighter-t-enlighter enlighter-hover enlighter-overflow-scroll">
<div class="enlighter-toolbar">
<div class="enlighter-btn enlighter-btn-raw"></div>
<div class="enlighter-btn enlighter-btn-copy"></div>
<div class="enlighter-btn enlighter-btn-window"></div>
</div>
<div class="enlighter">
<div class="">
<div><span class="enlighter-c0"># ansible test71 -m debug -a "msg={{inventory_dir}}"</span></div>
</div>
<div class="">
<div><span class="enlighter-text">test71 </span><span class="enlighter-g0">|</span><span class="enlighter-text"> SUCCESS =</span><span class="enlighter-g1">&gt;</span> <span class="enlighter-g1">{</span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"changed"</span><span class="enlighter-text">: </span><span class="enlighter-k1">false</span><span class="enlighter-text">, </span></div>
</div>
<div class="">
<div><span class="enlighter-s0">"msg"</span><span class="enlighter-text">: </span><span class="enlighter-s0">"/etc/ansible"</span></div>
</div>
<div class="">
<div><span class="enlighter-g1">}</span></div>
</div>
</div>
</div>
&nbsp;

ansible中还有其他的一些变量的使用方法，但是需要结合其他的一些知识点，所以之后遇到了实际的使用场景，我们再进行介绍吧。

这篇文章就先总结到这里，希望能够对你有所帮助。

转载自朱双印日志https://www.zsythink.net/archives/2715

Last modification：May 29, 2024

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ansible笔记（18）：变量（五）

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