<p>If you don’t want to use ssh-agent and want to instead SSH with a
password instead of keys, you can with <ttclass="docutils literal"><spanclass="pre">--ask-pass</span></tt> (<ttclass="docutils literal"><spanclass="pre">-k</span></tt>), but
it’s much better to just use ssh-agent.</p>
<p>Now to run the command on all servers in a group, in this case,
<em>atlanta</em>, in 10 parallel forks:</p>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible atlanta -a <spanclass="s2">"/sbin/reboot"</span> -f 10
</pre></div>
</div>
<p>If you want to run commands as a different user than root, it looks like this:</p>
<divclass="highlight-python"><pre>ansible atlanta -a "/usr/bin/foo" -u yourname</pre>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible atlanta -a <spanclass="s2">"/usr/bin/foo"</span> -u yourname
</pre></div>
</div>
<p>If you want to run commands through sudo:</p>
<divclass="highlight-python"><pre>ansible atlanta -a "/usr/bin/foo" -u yourname --sudo [--ask-sudo-pass]</pre>
</div>
<p>Use –ask-sudo-pass (-K) if you are not using passwordless sudo. This will interactively prompt
you for the password to use. Use of passwordless sudo makes things easier to automate, but it’s
not required.</p>
<p>It is also possible to sudo to a user other than root using –sudo-user (-U):</p>
<divclass="highlight-python"><pre>ansible atlanta -a "/usr/bin/foo" -u yourname -U otheruser [--ask-sudo-pass]</pre>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible atlanta -a <spanclass="s2">"/usr/bin/foo"</span> -u yourname --sudo <spanclass="o">[</span>--ask-sudo-pass<spanclass="o">]</span>
</pre></div>
</div>
<p>Use <ttclass="docutils literal"><spanclass="pre">--ask-sudo-pass</span></tt> (<ttclass="docutils literal"><spanclass="pre">-K</span></tt>) if you are not using passwordless
sudo. This will interactively prompt you for the password to use.
Use of passwordless sudo makes things easier to automate, but it’s not
required.</p>
<p>It is also possible to sudo to a user other than root using
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible atlanta -a <spanclass="s2">"/usr/bin/foo"</span> -u yourname -U otheruser <spanclass="o">[</span>--ask-sudo-pass<spanclass="o">]</span>
</pre></div>
</div>
<p>Ok, so those are basics. If you didn’t read about patterns and groups yet, go back and read <aclass="reference internal"href="patterns.html"><em>Inventory & Patterns</em></a>.</p>
<p>The -f 10 in the above specifies the usage of 10 simultaneous processes. Normally commands also take
a <cite>-m</cite> for module name, but the default module name is ‘command’, so we didn’t need to specify that
all of the time. We’ll use <cite>-m</cite> in later examples to run some other <aclass="reference internal"href="modules.html"><em>Ansible Modules</em></a>.</p>
<p>Note that the command module requires absolute paths and does not support shell variables. If we want to
execute a module using the shell, we can do those things, and also use pipe and redirection operators.
Read more about the differences on the <aclass="reference internal"href="modules.html"><em>Ansible Modules</em></a> page. The shell
module looks like this:</p>
<divclass="highlight-python"><pre>ansible raleigh -m shell -a 'echo $TERM'</pre>
</div>
<p>When running any command with the ansible “ad hoc” CLI (as opposed to playbooks), pay particular attention
to shell quoting rules, so the shell doesn’t eat a variable before it gets passed to Ansible. For example,
using double vs single quotes in the above example would evaluate the variable on the box you were on.</p>
<p>So far we’ve been demoing simple command execution, but most ansible modules usually do not work like
<p>The <ttclass="docutils literal"><spanclass="pre">-f</span><spanclass="pre">10</span></tt> in the above specifies the usage of 10 simultaneous
processes. Normally commands also take a <ttclass="docutils literal"><spanclass="pre">-m</span></tt> for module name, but
the default module name is <aclass="reference internal"href="modules.html#command"><em>command</em></a>, so we didn’t need to
specify that all of the time. We’ll use <ttclass="docutils literal"><spanclass="pre">-m</span></tt> in later examples to
run some other <aclass="reference internal"href="modules.html"><em>Ansible Modules</em></a>.</p>
<divclass="admonition note">
<pclass="first admonition-title">Note</p>
<pclass="last">The <aclass="reference internal"href="modules.html#command"><em>command</em></a> module requires absolute paths and does not
support shell variables. If we want to execute a module using a
shell, we can do those things, and also use pipe and redirection
operators. Read more about the differences on the <aclass="reference internal"href="modules.html"><em>Ansible Modules</em></a>
page.</p>
</div>
<p>Using the <aclass="reference internal"href="modules.html#shell"><em>shell</em></a> module looks like this:</p>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible raleigh -m shell -a <spanclass="s1">'echo $TERM'</span>
</pre></div>
</div>
<p>When running any command with the ansible <em>ad hoc</em> CLI (as opposed to
<aclass="reference internal"href="playbooks.html"><em>Playbooks</em></a>), pay particular attention to shell quoting rules, so
the shell doesn’t eat a variable before it gets passed to Ansible.
For example, using double vs single quotes in the above example would
evaluate the variable on the box you were on.</p>
<p>So far we’ve been demoing simple command execution, but most Ansible modules usually do not work like
simple scripts. They make the remote system look like you state, and run the commands necessary to
get it there. This is commonly referred to as ‘idempotence’, and is a core design goal of ansible.
However, we also recognize that running ad-hoc commands is equally important, so Ansible easily supports both.</p>
However, we also recognize that running <em>ad hoc</em> commands is equally important, so Ansible easily supports both.</p>
</div>
<divclass="section"id="file-transfer-templating">
<h2>File Transfer & Templating<aclass="headerlink"href="#file-transfer-templating"title="Permalink to this headline">¶</a></h2>
@ -239,59 +258,70 @@ However, we also recognize that running ad-hoc commands is equally important, so
<p>Ansible can SCP lots of files to multiple machines in parallel, and
optionally use them as template sources.</p>
<p>To transfer a file directly to many different servers:</p>
<divclass="highlight-python"><pre>ansible atlanta -m copy -a "src=/etc/hosts dest=/tmp/hosts"</pre>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible atlanta -m copy -a <spanclass="s2">"src=/etc/hosts dest=/tmp/hosts"</span>
</pre></div>
</div>
<p>To use templating, first run the setup module to put the template
variables you would like to use on the remote host. Then use the
template module to write the files using those templates.</p>
<p>Templates are written in <aclass="reference external"href="http://jinja.pocoo.org/docs/">Jinja2</a> format.
Playbooks (covered elsewhere in the
documentation) will run the setup module for you, making this even
simpler:</p>
<divclass="highlight-python"><pre>ansible webservers -m setup -a "favcolor=red ntp_server=192.168.1.1"
ansible webservers -m template -a "src=/srv/motd.j2 dest=/etc/motd"
ansible webservers -m template -a "src=/srv/ntp.j2 dest=/etc/ntp.conf"</pre>
</div>
<p>Ansible variables are used in templates by using the name surrounded by double
curly-braces. Ansible provides some ‘facts’ about the system being managed
automatically in playbooks or when the setup module is run manually. If facter or ohai
were installed on the remote machine, variables
from those programs can be accessed too, using the appropriate prefix:</p>
<divclass="highlight-python"><pre>This is an Ansible variable: {{ favcolor }}
This is an Ansible fact: {{ ansible_hostname }}
This is a facter fact: {{ facter_hostname }}
This is an ohai fact: {{ ohai_foo }}</pre>
<p>Templates are written in <aclass="reference external"href="http://jinja.pocoo.org/docs/">Jinja2</a>
format. <aclass="reference internal"href="playbooks.html"><em>Playbooks</em></a> will run the setup module for you, making
this even simpler:</p>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible webservers -m setup -a <spanclass="s2">"favcolor=red ntp_server=192.168.1.1"</span>
<spanclass="nv">$ </span>ansible webservers -m template -a <spanclass="s2">"src=/srv/motd.j2 dest=/etc/motd"</span>
<spanclass="nv">$ </span>ansible webservers -m template -a <spanclass="s2">"src=/srv/ntp.j2 dest=/etc/ntp.conf"</span>
</pre></div>
</div>
<p>Ansible variables are used in templates by using the name surrounded
by double curly-braces. Ansible provides some <em>facts</em> about the
system being managed automatically in playbooks or when the setup
module is run manually. If facter or ohai were installed on the
remote machine, variables from those programs can be accessed too,
using the appropriate prefix:</p>
<divclass="highlight-django"><divclass="highlight"><pre><spanclass="x">This is an Ansible variable: </span><spanclass="cp">{{</span><spanclass="nv">favcolor</span><spanclass="cp">}}</span><spanclass="x"></span>
<spanclass="x">This is an Ansible fact: </span><spanclass="cp">{{</span><spanclass="nv">ansible_hostname</span><spanclass="cp">}}</span><spanclass="x"></span>
<spanclass="x">This is a facter fact: </span><spanclass="cp">{{</span><spanclass="nv">facter_hostname</span><spanclass="cp">}}</span><spanclass="x"></span>
<spanclass="x">This is an ohai fact: </span><spanclass="cp">{{</span><spanclass="nv">ohai_foo</span><spanclass="cp">}}</span><spanclass="x"></span>
</pre></div>
</div>
<p>Using the Ansible facts is generally preferred as that way you can avoid a dependency
on ruby. If you want to use facter instead, you will also need rubygem-json because
the facter packages may forget this as a dependency.</p>
<p>The <cite>file</cite> module allows changing ownership and permissions on files. These
same options can be passed directly to the <cite>copy</cite> or <cite>template</cite> modules as well:</p>
<divclass="highlight-python"><pre>ansible webservers -m file -a "dest=/srv/foo/a.txt mode=600"
ansible webservers -m file -a "dest=/srv/foo/b.txt mode=600 owner=mdehaan group=mdehaan"</pre>
<p>The <ttclass="docutils literal"><spanclass="pre">file</span></tt> module allows changing ownership and permissions on files. These
same options can be passed directly to the <ttclass="docutils literal"><spanclass="pre">copy</span></tt> or <ttclass="docutils literal"><spanclass="pre">template</span></tt> modules as well:</p>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible webservers -m file -a <spanclass="s2">"dest=/srv/foo/a.txt mode=600"</span>
<spanclass="nv">$ </span>ansible webservers -m file -a <spanclass="s2">"dest=/srv/foo/b.txt mode=600 owner=mdehaan group=mdehaan"</span>
</pre></div>
</div>
<p>The <cite>file</cite> module can also create directories, similar to <cite>mkdir -p</cite>:</p>
<divclass="highlight-python"><pre>ansible webservers -m file -a "dest=/path/to/c mode=644 owner=mdehaan group=mdehaan state=directory"</pre>
<p>The <ttclass="docutils literal"><spanclass="pre">file</span></tt> module can also create directories, similar to <ttclass="docutils literal"><spanclass="pre">mkdir</span><spanclass="pre">-p</span></tt>:</p>
<p>As well as delete directories (recursively) and delete files:</p>
<divclass="highlight-python"><pre>ansible webservers -m file -a "dest=/path/to/c state=absent"</pre>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible webservers -m file -a <spanclass="s2">"dest=/path/to/c state=absent"</span>
</pre></div>
</div>
<p>The mode, owner, and group arguments can also be used on the copy or template lines.</p>
</div>
<divclass="section"id="managing-packages">
<h2>Managing Packages<aclass="headerlink"href="#managing-packages"title="Permalink to this headline">¶</a></h2>
<p>There are modules available for yum and apt. Here are some examples with yum.</p>
<p>There are modules available for yum and apt. Here are some examples
with <aclass="reference internal"href="modules.html#yum"><em>yum</em></a>.</p>
<p>Ensure a package is installed, but don’t update it:</p>
<divclass="highlight-python"><pre>ansible webservers -m yum -a "pkg=acme state=installed"</pre>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible webservers -m yum -a <spanclass="s2">"pkg=acme state=installed"</span>
</pre></div>
</div>
<p>Ensure a package is installed to a specific version:</p>
<divclass="highlight-python"><pre>ansible webservers -m yum -a "pkg=acme-1.5 state=installed"</pre>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible webservers -m yum -a <spanclass="s2">"pkg=acme-1.5 state=installed"</span>
</pre></div>
</div>
<p>Ensure a package is at the latest version:</p>
<divclass="highlight-python"><pre>ansible webservers -m yum -a "pkg=acme state=latest"</pre>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible webservers -m yum -a <spanclass="s2">"pkg=acme state=latest"</span>
</pre></div>
</div>
<p>Ensure a package is not installed:</p>
<divclass="highlight-python"><pre>ansible webservers -m yum -a "pkg=acme state=removed"</pre>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible webservers -m yum -a <spanclass="s2">"pkg=acme state=removed"</span>
</pre></div>
</div>
<p>Currently Ansible only has modules for managing packages with yum and apt. You can install
for other packages for now using the command module or (better!) contribute a module
@ -299,11 +329,13 @@ for other package managers. Stop by the mailing list for info/details.</p>
</div>
<divclass="section"id="users-and-groups">
<h2>Users and Groups<aclass="headerlink"href="#users-and-groups"title="Permalink to this headline">¶</a></h2>
<p>The user module allows easy creation and manipulation of existing user accounts, as well
as removal of user accounts that may exist:</p>
<divclass="highlight-python"><pre>ansible all -m user -a "name=foo password=<crypted password here>"
<p>The <aclass="reference internal"href="modules.html#user"><em>user</em></a> module allows easy creation and manipulation of
existing user accounts, as well as removal of user accounts that may
exist:</p>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible all -m user -a <spanclass="s2">"name=foo password=<crypted password here>"</span>
ansible all -m user -a "name=foo state=absent"</pre>
<spanclass="nv">$ </span>ansible all -m user -a <spanclass="s2">"name=foo state=absent"</span>
</pre></div>
</div>
<p>See the <aclass="reference internal"href="modules.html"><em>Ansible Modules</em></a> section for details on all of the available options, including
how to manipulate groups and group membership.</p>
@ -311,23 +343,27 @@ how to manipulate groups and group membership.</p>
<h2>Deploying From Source Control<aclass="headerlink"href="#deploying-from-source-control"title="Permalink to this headline">¶</a></h2>
<p>Deploy your webapp straight from git:</p>
<divclass="highlight-python"><pre>ansible webservers -m git -a "repo=git://foo.example.org/repo.git dest=/srv/myapp version=HEAD"</pre>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible webservers -m git -a <spanclass="s2">"repo=git://foo.example.org/repo.git dest=/srv/myapp version=HEAD"</span>
</pre></div>
</div>
<p>Since ansible modules can notify change handlers (see
<aclass="reference internal"href="playbooks.html"><em>Playbooks</em></a>) it is possible to tell ansible to run specific tasks
when the code is updated, such as deploying Perl/Python/PHP/Ruby
directly from git and then restarting apache.</p>
<p>Since ansible modules can notify change handlers it is possible to
tell ansible to run specific tasks when the code is updated, such as
deploying Perl/Python/PHP/Ruby directly from git and then restarting
apache.</p>
</div>
<divclass="section"id="managing-services">
<h2>Managing Services<aclass="headerlink"href="#managing-services"title="Permalink to this headline">¶</a></h2>
<p>Ensure a service is started on all webservers:</p>
<divclass="highlight-python"><pre>ansible webservers -m service -a "name=httpd state=started"</pre>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible webservers -m service -a <spanclass="s2">"name=httpd state=started"</span>
</pre></div>
</div>
<p>Alternatively, restart a service on all webservers:</p>
<divclass="highlight-python"><pre>ansible webservers -m service -a "name=httpd state=restarted"</pre>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible webservers -m service -a <spanclass="s2">"name=httpd state=restarted"</span>
</pre></div>
</div>
<p>Ensure a service is stopped:</p>
<divclass="highlight-python"><pre>ansible webservers -m service -a "name=httpd state=stopped"</pre>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible webservers -m service -a <spanclass="s2">"name=httpd state=stopped"</span>
@ -336,20 +372,24 @@ directly from git and then restarting apache.</p>
checked on later. The same job ID is given to the same task on all
hosts, so you won’t lose track. If you kick hosts and don’t want
to poll, it looks like this:</p>
<divclass="highlight-python"><pre>ansible all -B 3600 -a "/usr/bin/long_running_operation --do-stuff"</pre>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible all -B 3600 -a <spanclass="s2">"/usr/bin/long_running_operation --do-stuff"</span>
</pre></div>
</div>
<p>If you do decide you want to check on the job status later, you can:</p>
<divclass="highlight-python"><pre>ansible all -m async_status -a "jid=123456789"</pre>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible all -m async_status -a <spanclass="s2">"jid=123456789"</span>
</pre></div>
</div>
<p>Polling is built-in and looks like this:</p>
<divclass="highlight-python"><pre>ansible all -B 3600 -P 60 -a "/usr/bin/long_running_operation --do-stuff"</pre>
<divclass="highlight-bash"><divclass="highlight"><pre><spanclass="nv">$ </span>ansible all -B 1800 -P 60 -a <spanclass="s2">"/usr/bin/long_running_operation --do-stuff"</span>
</pre></div>
</div>
<p>The above example says “run for 60 minutes max (60*60=3600), poll for status every 60 seconds”.</p>
<p>The above example says “run for 30 minutes max (<ttclass="docutils literal"><spanclass="pre">-B</span></tt>: 30*60=1800),
poll for status (<ttclass="docutils literal"><spanclass="pre">-P</span></tt>) every 60 seconds”.</p>
<p>Poll mode is smart so all jobs will be started before polling will begin on any machine.
Be sure to use a high enough <cite>–forks</cite> value if you want to get all of your jobs started
Be sure to use a high enough <tt class="docutils literal"><spanclass="pre">--forks</span></tt> value if you want to get all of your jobs started
very quickly. After the time limit (in seconds) runs out (<ttclass="docutils literal"><spanclass="pre">-B</span></tt>), the process on
the remote nodes will be terminated.</p>
<p>Any module other than <cite>copy</cite> or <cite>template</cite> can be
<p>Any module other than <tt class="docutils literal"><spanclass="pre">copy</span></tt> or <ttclass="docutils literal"><spanclass="pre">template</span></tt> can be
backgrounded. Typically you’ll be backgrounding long-running
shell commands or software upgrades only. <aclass="reference internal"href="playbooks.html"><em>Playbooks</em></a> also support polling, and have
Michael DeHaan
12 years ago