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<li><a class="reference internal" href="#group-by-roles">Group By Roles</a></li>
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<li><a class="reference internal" href="#directory-organization">Directory Organization</a></li>
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<li><a class="reference internal" href="#bundling-ansible-modules-with-playbooks">Bundling Ansible Modules With Playbooks</a></li>
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<li><a class="reference internal" href="#miscellaneous-tips">Miscellaneous Tips</a></li>
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<div class="section" id="best-practices">
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<h1><a class="toc-backref" href="#contents">Best Practices</a><a class="headerlink" href="#best-practices" title="Permalink to this headline">¶</a></h1>
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<p>Here are some tips for making the most of Ansible.</p>
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<div class="contents topic" id="contents">
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<p class="topic-title first">Contents</p>
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<ul class="simple">
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<li><a class="reference internal" href="#best-practices" id="id1">Best Practices</a><ul>
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<li><a class="reference internal" href="#always-mention-state" id="id2">Always Mention State</a></li>
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<li><a class="reference internal" href="#group-by-roles" id="id3">Group By Roles</a></li>
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<li><a class="reference internal" href="#directory-organization" id="id4">Directory Organization</a></li>
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<li><a class="reference internal" href="#bundling-ansible-modules-with-playbooks" id="id5">Bundling Ansible Modules With Playbooks</a></li>
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<li><a class="reference internal" href="#miscellaneous-tips" id="id6">Miscellaneous Tips</a></li>
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</ul>
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</li>
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</ul>
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</div>
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<div class="section" id="always-mention-state">
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<h2><a class="toc-backref" href="#contents">Always Mention State</a><a class="headerlink" href="#always-mention-state" title="Permalink to this headline">¶</a></h2>
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<p>The ‘state’ parameter is optional to a lot of modules. Whether
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‘state=present’ or ‘state=absent’, it’s always best to leave that
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parameter in your playbooks to make it clear, especially as some
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modules support additional states.</p>
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</div>
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<div class="section" id="group-by-roles">
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<h2><a class="toc-backref" href="#contents">Group By Roles</a><a class="headerlink" href="#group-by-roles" title="Permalink to this headline">¶</a></h2>
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<p>A system can be in multiple groups. See <a class="reference internal" href="patterns.html"><em>Inventory & Patterns</em></a>. Having groups named after things like
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<em>webservers</em> and <em>dbservers</em> is repeated in the examples because it’s a very powerful concept.</p>
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<p>This allows playbooks to target machines based on role, as well as to assign role specific variables
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using the group variable system.</p>
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</div>
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<div class="section" id="directory-organization">
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<h2><a class="toc-backref" href="#contents">Directory Organization</a><a class="headerlink" href="#directory-organization" title="Permalink to this headline">¶</a></h2>
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<p>Playbooks should be organized like this:</p>
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<div class="highlight-python"><pre># root of source control repository
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├── acme/
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│ ├── setup.yml
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│ └── stop.yml
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├── files/
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│ └── some_file_path_foo.conf
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├── handlers/
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│ └── main.yml
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├── tasks/
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│ ├── setup.yml
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│ └── stop.yml
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├── templates/
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│ ├── etc_acme_conf_acme.conf
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│ └── etc_other_conf_other.conf
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├── vars/
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│ └── main.yml
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└── global_vars.yml</pre>
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</div>
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<p>Any directories or files not needed can be omitted. Not all modules
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may require ‘vars’ or ‘files’ sections, though most will require
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‘handlers’, ‘tasks’, and ‘templates’. To review what each of
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these sections do, see <a class="reference internal" href="playbooks.html"><em>Playbooks</em></a> and <a class="reference internal" href="playbooks2.html"><em>Advanced Playbooks</em></a>.</p>
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<p>The acme/setup.yml playbook would be as simple as:</p>
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<div class="highlight-python"><pre>---
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- hosts: webservers
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user: root
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vars_files:
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- ../global_vars.yml
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- vars/main.yml
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tasks:
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- include: tasks/setup.yml
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handlers:
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- include: handlers/main.yml</pre>
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</div>
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<p>The tasks are individually broken out in ‘acme/tasks/setup.yml’, and handlers, which are common to all task files,
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are contained in ‘acme/handlers/main.yml’. As a reminder, handlers are mostly just used to notify services to restart
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when things change, and these are described in <a class="reference internal" href="playbooks.html"><em>Playbooks</em></a>.</p>
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<p>Including more than one setup file or more than one handlers file is of course legal.</p>
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</div>
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<div class="section" id="bundling-ansible-modules-with-playbooks">
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<h2><a class="toc-backref" href="#contents">Bundling Ansible Modules With Playbooks</a><a class="headerlink" href="#bundling-ansible-modules-with-playbooks" title="Permalink to this headline">¶</a></h2>
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<p class="versionadded">
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<span class="versionmodified">New in version 0.5.</span></p>
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<p>If a playbook has a ”./library” directory relative to it’s YAML file,
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this directory can be used to add ansible modules that will
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automatically be in the ansible module path. This is a great way to
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keep modules that go with a playbook together.</p>
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</div>
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<div class="section" id="miscellaneous-tips">
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<h2><a class="toc-backref" href="#contents">Miscellaneous Tips</a><a class="headerlink" href="#miscellaneous-tips" title="Permalink to this headline">¶</a></h2>
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<p>When you can do something simply, do something simply. Do not reach
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to use every feature of Ansible together, all at once. Use what works
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for you. For example, you should probably not need ‘vars’,
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‘vars_files’, ‘vars_prompt’ and ‘–extra-vars’ all at once,
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while also using an external inventory file.</p>
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<p>Optimize for readability. Whitespace between sections of YAML
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documents and in between tasks is strongly encouraged, as is usage of
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YAML comments, which start with ‘#’. It is also useful to comment
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at the top of each file the purpose of the individual file and the
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author, including email address.</p>
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<p>It is possible to leave off the ‘name’ for a given task, though it
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is recommended to provide a descriptive comment about why something is
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being done instead.</p>
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<p>Use version control. Keep your playbooks and inventory file in git
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(or another version control system), and commit when you make changes
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to them. This way you have an audit trail describing when and why you
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changed the rules automating your infrastructure.</p>
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<p>Resist the urge to write the same playbooks and configuration files
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for heterogeneous distributions. While lots of software packages
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claim to make this easy on you, the configuration files are often
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quite different, to the point where it would be easier to treat them
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as different playbooks. This is why, for example, Ansible has a
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separate ‘yum’ and ‘apt’ module. Yum and apt have different
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capabilities, and we don’t want to code for the least common
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denominator.</p>
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<p>Use variables for user tunable settings versus having constants in the
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tasks file or templates, so that it is easy to reconfigure a playbook.
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Think about this as exposing the knobs to things you would like to
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tweak.</p>
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<p>Since a system can be in more than one group, if you have multiple
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datacenters or sites, consider putting systems into groups by role,
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but also different groups by geography. This allows you to assign
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different variables to different geographies.</p>
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<div class="admonition-see-also admonition seealso">
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<p class="first admonition-title">See also</p>
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<dl class="last docutils">
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<dt><a class="reference internal" href="YAMLSyntax.html"><em>YAML Syntax</em></a></dt>
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<dd>Learn about YAML syntax</dd>
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<dt><a class="reference internal" href="playbooks.html"><em>Playbooks</em></a></dt>
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<dd>Review the basic playbook features</dd>
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<dt><a class="reference internal" href="modules.html"><em>Ansible Modules</em></a></dt>
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<dd>Learn about available modules</dd>
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<dt><a class="reference internal" href="moduledev.html"><em>Module Development</em></a></dt>
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<dd>Learn how to extend Ansible by writing your own modules</dd>
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<dt><a class="reference internal" href="patterns.html"><em>Inventory & Patterns</em></a></dt>
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<dd>Learn about how to select hosts</dd>
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<dt><a class="reference external" href="https://github.com/ansible/ansible/tree/devel/examples/playbooks">Github examples directory</a></dt>
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<dd>Complete playbook files from the github project source</dd>
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<dt><a class="reference external" href="http://groups.google.com/group/ansible-project">Mailing List</a></dt>
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<dd>Questions? Help? Ideas? Stop by the list on Google Groups</dd>
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</dl>
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</div>
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</div>
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<p>
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© Copyright 2012 Michael DeHaan.<br/>
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Last updated on Oct 04, 2012.<br/>
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