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<a class="brand" href="#">Ansible</a>
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class="dropdown-toggle">Chapter</a>
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<li class="toctree-l1"><a class="reference internal" href="gettingstarted.html">Downloads &amp; Getting Started</a></li>
<li class="toctree-l1"><a class="reference internal" href="patterns.html">The Inventory File, Patterns, and Groups</a></li>
<li class="toctree-l1"><a class="reference internal" href="examples.html">Command Line Examples</a></li>
<li class="toctree-l1"><a class="reference internal" href="modules.html">Ansible Modules</a></li>
<li class="toctree-l1"><a class="reference internal" href="YAMLSyntax.html">YAML Syntax</a></li>
<li class="toctree-l1"><a class="reference internal" href="playbooks.html">Playbooks</a></li>
<li class="toctree-l1"><a class="reference internal" href="api.html">API &amp; Integrations</a></li>
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<li><a class="reference internal" href="#">Introducing Ansible</a><ul>
<li><a class="reference internal" href="#architecture">Architecture</a></li>
<li><a class="reference internal" href="#features">Features</a></li>
<li><a class="reference internal" href="#resources">Resources</a></li>
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<li><a class="reference internal" href="#contents">Contents</a><ul>
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<a class="reference external image-reference" href="http://photos.michaeldehaan.net/infrared/h3d850bdf#h3d850bdf"><img alt="&quot;&quot;" src="http://ansible.github.com/mpd_rings.jpg" style="width: 300px; height: 225px;" /></a>
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<div class="section" id="introducing-ansible">
<h1>Introducing Ansible<a class="headerlink" href="#introducing-ansible" title="Permalink to this headline"></a></h1>
<p>Ansible is a radically simple deployment, model-driven configuration management,
and command execution framework. Other tools in this space have been too
complicated for too long, require too much bootstrapping, and have too
much learning curve. Ansible is dead simple and painless to extend.
For comparison, Puppet and Chef have about 60k lines of code.
Ansible&#8217;s core is a little over 1000 lines.</p>
<p>Ansible isn&#8217;t just for idempotent configuration &#8211; it&#8217;s also great for ad-hoc
tasks, quickly firing off commands against nodes. See <a class="reference internal" href="examples.html"><em>Command Line Examples</em></a>.</p>
<p>Where Ansible excels though, is expressing complex multi-node
deployment processes, executing ordered sequences on
different sets of nodes through <a class="reference internal" href="playbooks.html"><em>Playbooks</em></a>. Playbooks contain one or
more plays, each executed against a different batch of nodes. Think about
webservers, database servers, and backend servers in a multi-node web environment. A play could address each set of machines in a cycle, ensuring the configurations of the machines were correct and also updating them to the specified
version of software if required.</p>
<p>Multi-machine software deployment is poorly solved by most systems management tools &#8211; often due to architectural nature of being pull oriented and having complex ordering systems, they cover configuration but fail at deployment when updating tiers of machines in well defined steps. This results in using two (or more) logically distinct tools and having complex overlap between them.</p>
<p>Other deployment oriented frameworks similarly cover deployment well but lack a strongly defined resource model and devolve into glorified remote scripts. Ansible playbooks &#8211; having been designed with this problem in mind &#8211; are good at both deployment &amp; idempotent configuration, meaning you don&#8217;t have to spread your infrastructure management out between different tools (Puppet+Capistrano, Chef+Fabric, etc), and performing ordered steps between different classes of machines is no problem, yet our modules affect system state only when required &#8211; while avoiding the problem of fragile scripting that assumes certain starting
or ending states.</p>
<p>Ansible is also unique in other ways. Extending ansible does not require programming in any particular language &#8211; you can write <a class="reference internal" href="modules.html"><em>Ansible Modules</em></a> as idempotent scripts or programs that return simple JSON. Ansible is also pragmatic, so when you need to, it&#8217;s also trivially easy to just execute useful shell commands.</p>
<p>Why use Ansible versus something else? (Puppet, Chef, Capistrano, etc?) Ansible will have far
less code, it will be (by extension) more correct, and it will be the
easiest thing to hack on and use you&#8217;ll ever see &#8211; regardless of your
favorite language of choice.</p>
<p>Systems management doesn&#8217;t have to be complicated. Ansible&#8217;s docs
will remain short &amp; simple, and the source will be blindingly obvious.</p>
<p>We&#8217;ve learned well from &#8220;Infrastructure is Code&#8221;. Infrastructure should be easy and powerful to command, but it should not look like code, lest it acquire the disadvantages of a software project &#8211; bugs, complexity, and overhead. Infrastructure configurations should be simple, easy to develop, and easy to audit.</p>
<div class="section" id="architecture">
<h2>Architecture<a class="headerlink" href="#architecture" title="Permalink to this headline"></a></h2>
13 years ago
<img alt="&quot;Architecture Diagram&quot;" src="http://ansible.github.com/ansible_arch2.jpg" style="width: 800px;" />
</div>
<div class="section" id="features">
<h2>Features<a class="headerlink" href="#features" title="Permalink to this headline"></a></h2>
<ul class="simple">
<li>Dead simple setup</li>
<li>Super fast &amp; parallel by default</li>
<li>No server or client daemons; use existing SSHd out of the box</li>
<li>No additional software required on client boxes</li>
<li>Can be easily run from a checkout, no installation required</li>
<li>Modules are idempotent, but you can also easily use shell commands</li>
<li>Modules can be written in ANY language</li>
<li>Awesome API for creating very powerful distributed scripts</li>
<li>Does not have to run remote steps as root</li>
<li>Pluggable transports (SSH is just the default)</li>
<li>Source host info &amp; variables from files or external software</li>
<li>The easiest config management system to use, ever.</li>
</ul>
</div>
<div class="section" id="resources">
<h2>Resources<a class="headerlink" href="#resources" title="Permalink to this headline"></a></h2>
<p>Your ideas and contributions are welcome. We&#8217;re also happy to help
you with questions about Ansible.</p>
<ul class="simple">
<li>Visit the <a class="reference external" href="https://github.com/ansible/ansible">project page</a> on Github</li>
<li>View the <a class="reference external" href="https://github.com/ansible/ansible/issues">issue tracker</a></li>
<li>Visit the <a class="reference external" href="http://groups.google.com/group/ansible-project">Google Group</a></li>
13 years ago
<li>Chat on <a class="reference external" href="http://webchat.freenode.net/?channels=ansible">FreeNode</a></li>
</ul>
<img src="http://groups.google.com/intl/en/images/logos/groups_logo_sm.gif" height=30 width=140 alt="Google Groups">
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<b>Subscribe to Ansible Project</b>
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<div class="section" id="contents">
<h1>Contents<a class="headerlink" href="#contents" title="Permalink to this headline"></a></h1>
<div class="toctree-wrapper compound">
<ul>
<li class="toctree-l1"><a class="reference internal" href="gettingstarted.html">Downloads &amp; Getting Started</a><ul>
<li class="toctree-l2"><a class="reference internal" href="gettingstarted.html#requirements">Requirements</a></li>
<li class="toctree-l2"><a class="reference internal" href="gettingstarted.html#getting-ansible">Getting Ansible</a><ul>
<li class="toctree-l3"><a class="reference internal" href="gettingstarted.html#running-from-checkout">Running From Checkout</a></li>
<li class="toctree-l3"><a class="reference internal" href="gettingstarted.html#make-install">Make Install</a></li>
<li class="toctree-l3"><a class="reference internal" href="gettingstarted.html#via-rpm">Via RPM</a></li>
<li class="toctree-l3"><a class="reference internal" href="gettingstarted.html#other-package-distributions">Other Package Distributions</a></li>
<li class="toctree-l3"><a class="reference internal" href="gettingstarted.html#tagged-releases">Tagged Releases</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="gettingstarted.html#your-first-commands">Your first commands</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="patterns.html">The Inventory File, Patterns, and Groups</a><ul>
<li class="toctree-l2"><a class="reference internal" href="patterns.html#inventory-file-format">Inventory File Format</a></li>
<li class="toctree-l2"><a class="reference internal" href="patterns.html#selecting-targets">Selecting Targets</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="examples.html">Command Line Examples</a><ul>
<li class="toctree-l2"><a class="reference internal" href="examples.html#parallelism-and-shell-commands">Parallelism and Shell Commands</a></li>
<li class="toctree-l2"><a class="reference internal" href="examples.html#file-transfer-templating">File Transfer &amp; Templating</a></li>
<li class="toctree-l2"><a class="reference internal" href="examples.html#managing-packages">Managing Packages</a></li>
<li class="toctree-l2"><a class="reference internal" href="examples.html#users-and-groups">Users and Groups</a></li>
<li class="toctree-l2"><a class="reference internal" href="examples.html#deploying-from-source-control">Deploying From Source Control</a></li>
<li class="toctree-l2"><a class="reference internal" href="examples.html#managing-services">Managing Services</a></li>
<li class="toctree-l2"><a class="reference internal" href="examples.html#time-limited-background-operations">Time Limited Background Operations</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="modules.html">Ansible Modules</a><ul>
<li class="toctree-l2"><a class="reference internal" href="modules.html#apt">apt</a></li>
<li class="toctree-l2"><a class="reference internal" href="modules.html#id1">command</a></li>
<li class="toctree-l2"><a class="reference internal" href="modules.html#copy">copy</a></li>
<li class="toctree-l2"><a class="reference internal" href="modules.html#facter">facter</a></li>
<li class="toctree-l2"><a class="reference internal" href="modules.html#file">file</a></li>
<li class="toctree-l2"><a class="reference internal" href="modules.html#git">git</a></li>
<li class="toctree-l2"><a class="reference internal" href="modules.html#ohai">ohai</a></li>
<li class="toctree-l2"><a class="reference internal" href="modules.html#ping">ping</a></li>
<li class="toctree-l2"><a class="reference internal" href="modules.html#service">service</a></li>
<li class="toctree-l2"><a class="reference internal" href="modules.html#setup">setup</a></li>
<li class="toctree-l2"><a class="reference internal" href="modules.html#shell">shell</a></li>
<li class="toctree-l2"><a class="reference internal" href="modules.html#template">template</a></li>
<li class="toctree-l2"><a class="reference internal" href="modules.html#user">user</a></li>
<li class="toctree-l2"><a class="reference internal" href="modules.html#yum">yum</a></li>
<li class="toctree-l2"><a class="reference internal" href="modules.html#writing-your-own-modules">Writing your own modules</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="YAMLSyntax.html">YAML Syntax</a><ul>
<li class="toctree-l2"><a class="reference internal" href="YAMLSyntax.html#yaml-basics">YAML Basics</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="playbooks.html">Playbooks</a><ul>
<li class="toctree-l2"><a class="reference internal" href="playbooks.html#playbook-example">Playbook Example</a></li>
<li class="toctree-l2"><a class="reference internal" href="playbooks.html#basics">Basics</a><ul>
<li class="toctree-l3"><a class="reference internal" href="playbooks.html#hosts-and-users">Hosts and Users</a></li>
<li class="toctree-l3"><a class="reference internal" href="playbooks.html#vars-section">Vars section</a></li>
<li class="toctree-l3"><a class="reference internal" href="playbooks.html#tasks-list">Tasks list</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="playbooks.html#running-operations-on-change">Running Operations On Change</a></li>
<li class="toctree-l2"><a class="reference internal" href="playbooks.html#power-tricks">Power Tricks</a><ul>
<li class="toctree-l3"><a class="reference internal" href="playbooks.html#external-variables-and-sensitive-data">External Variables And Sensitive Data</a></li>
<li class="toctree-l3"><a class="reference internal" href="playbooks.html#conditional-execution">Conditional Execution</a></li>
<li class="toctree-l3"><a class="reference internal" href="playbooks.html#conditional-imports">Conditional Imports</a></li>
<li class="toctree-l3"><a class="reference internal" href="playbooks.html#include-files-and-reuse">Include Files And Reuse</a></li>
<li class="toctree-l3"><a class="reference internal" href="playbooks.html#using-includes-to-assign-classes-of-systems">Using Includes To Assign Classes of Systems</a></li>
<li class="toctree-l3"><a class="reference internal" href="playbooks.html#asynchronous-actions-and-polling">Asynchronous Actions and Polling</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="playbooks.html#executing-a-playbook">Executing A Playbook</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="api.html">API &amp; Integrations</a><ul>
<li class="toctree-l2"><a class="reference internal" href="api.html#python-api">Python API</a><ul>
<li class="toctree-l3"><a class="reference internal" href="api.html#detailed-api-example">Detailed API Example</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="api.html#external-inventory">External Inventory</a><ul>
<li class="toctree-l3"><a class="reference internal" href="api.html#script-conventions">Script Conventions</a></li>
<li class="toctree-l3"><a class="reference internal" href="api.html#example-the-cobbler-external-inventory-script">Example: The Cobbler External Inventory Script</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="moduledev.html">Module Development Guide</a><ul>
<li class="toctree-l2"><a class="reference internal" href="moduledev.html#tutorial">Tutorial</a></li>
<li class="toctree-l2"><a class="reference internal" href="moduledev.html#testing-modules">Testing Modules</a></li>
<li class="toctree-l2"><a class="reference internal" href="moduledev.html#reading-input">Reading Input</a></li>
<li class="toctree-l2"><a class="reference internal" href="moduledev.html#common-pitfalls">Common Pitfalls</a></li>
<li class="toctree-l2"><a class="reference internal" href="moduledev.html#conventions">Conventions</a></li>
<li class="toctree-l2"><a class="reference internal" href="moduledev.html#shorthand-vs-json">Shorthand Vs JSON</a></li>
<li class="toctree-l2"><a class="reference internal" href="moduledev.html#sharing-your-module">Sharing Your Module</a></li>
<li class="toctree-l2"><a class="reference internal" href="moduledev.html#getting-your-module-into-core">Getting Your Module Into Core</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="faq.html">Frequently Asked Questions</a><ul>
<li class="toctree-l2"><a class="reference internal" href="faq.html#what-inspired-ansible">What inspired Ansible?</a></li>
<li class="toctree-l2"><a class="reference internal" href="faq.html#comparisons">Comparisons</a><ul>
<li class="toctree-l3"><a class="reference internal" href="faq.html#vs-func">vs Func?</a></li>
<li class="toctree-l3"><a class="reference internal" href="faq.html#vs-puppet">vs Puppet?</a></li>
<li class="toctree-l3"><a class="reference internal" href="faq.html#vs-chef">vs Chef?</a></li>
<li class="toctree-l3"><a class="reference internal" href="faq.html#vs-capistrano-fabric">vs Capistrano/Fabric?</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="faq.html#other-questions">Other Questions</a><ul>
<li class="toctree-l3"><a class="reference internal" href="faq.html#how-does-ansible-scale">How does Ansible scale?</a></li>
<li class="toctree-l3"><a class="reference internal" href="faq.html#are-transports-other-than-ssh-supported">Are transports other than SSH supported?</a></li>
<li class="toctree-l3"><a class="reference internal" href="faq.html#what-are-some-ideal-uses-for-ansible">What are some ideal uses for Ansible?</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="man.html">Man Pages</a><ul>
<li class="toctree-l2"><a class="reference internal" href="man.html#ansible-1">ansible(1)</a></li>
<li class="toctree-l2"><a class="reference internal" href="man.html#ansible-playbook-1">ansible-playbook(1)</a></li>
</ul>
</li>
</ul>
</div>
<div class="section" id="about-the-author">
<h2>About the Author<a class="headerlink" href="#about-the-author" title="Permalink to this headline"></a></h2>
<p>Ansible was originally developed by <a class="reference external" href="http://michaeldehaan.net">Michael DeHaan</a> (<a class="reference external" href="http://twitter.com/#!/laserllama">&#64;laserllama</a>), a Raleigh, NC
based software developer and architect. He created the popular
DevOps program <a class="reference external" href="http://cobbler.github.com/">Cobbler</a>.
Cobbler is used to deploy mission critical systems all over the
planet, in industries ranging from massively multiplayer gaming, core
internet infrastructure, finance, chip design, and more. Michael also
helped co-author <a class="reference external" href="http://fedorahosted.org/func/">Func</a>, a precursor to Ansible, which is used to
orchestrate systems in lots of diverse places. He&#8217;s worked on systems
software for IBM, Motorola, Red Hat&#8217;s Emerging Technologies Group,
Puppet Labs, and rPath. Reach Michael by email <a class="reference external" href="mailto:michael&#46;dehaan&#37;&#52;&#48;gmail&#46;com">here</a>.</p>
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&copy; Copyright 2012 Michael DeHaan.<br/>
Last updated on Mar 31, 2012.<br/>
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13 years ago
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