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[[wp:Ansible_(software)]] is an open-source software platform for configuring and managing computers. It combines multi-node software deployment, ad hoc task execution, and configuration management. Written in Python, it is packaged by [[RedHat]]. As of July 2016, we're using Ansible 2.2.0
 
A lot of this page is outdated.
 
 
Also, RedHat seems to have purposely made things very convoluted in terms of versioning, release cycles and product naming. So check https://docs.ansible.com/ansible/latest/reference_appendices/release_and_maintenance.html and see if you can figure it out.
 
==Installation==
The preferred way to [http://docs.ansible.com/intro_installation.html install] is to just <code>git clone</code> the source. Having the source makes it easy to upgrade, and it's self-contained, plus best of all you get all the examples and contribs.
 
<source lang="bash">
cd
mkdir ~/bin
cd bin
git clone git://github.com/ansible/ansible.git --recursive
cd ./ansible
source ./hacking/env-setup
</source>
 
If you see this error message:
<pre>
Traceback (most recent call last):
File "/usr/local/bin/ansible-playbook", line 44, in <module>
import ansible.constants as C
ImportError: No module named ansible.constants
</pre>
Be sure to source the env-setup script
 
==Getting Started==
You must source the environment setup script to begin using Ansible (assuming you are running from a git checkout) <code>source ~/bin/ansible/hacking/env-setup</code>
Ansible provides three main commands:
# <code>ansible-playbook</code> - to execute an Ansible playbook on the specified systems
# <code>ansible</code> - to execute an individual shell command or Ansible module on the specified systems
# <code>ansible-vault</code> - (optional) to encrypt or decrypt YAML files that Ansible uses.
#<code>ansible-playbook</code> - to execute an Ansible playbook on the specified systems#<code>ansible</code> - to execute an individual shell command or Ansible module on the specified systems#<code>ansible-vault</code> - (optional) to encrypt or decrypt YAML files that Ansible uses. ===Global Config===<code>export ANSIBLE_HOST_KEY_CHECKING=False</code>or set it in your ~/.ansible.cfg so that as you add new hosts it won't prompt you. Also [https://docs.ansible.com/ansible/intro_getting_started.html#your-first-commands use 'ssh' instead of paramiko] when doing this. ===Initialize a Project===Use '''[https://galaxy.ansible.com/ui/ Ansible Galaxy]''' If you want to do a new project, you can use the <code>ansible-galaxy foo init</code> command which will create the directory and file structure for 'foo' in the current working directory. Also, if you want to install other Ansible Galaxy projects, you can either do it "manually" <code> ansible-galaxy install -r </code> Or, setup a 'requirements.yml' file in your playbook that then gets run by your stack. <ref>https://stackoverflow.com/questions/25230376/how-to-automatically-install-ansible-galaxy-roles</ref> <ref>Supposedly this only works for newer versions of Ansible, per the warning on their homepage:<blockquote> Warning alert:To be able to download content from galaxy it is required to have ansible-core>=2.13.9 Please, check it running the command: ansible --version</blockquote> '''But''', it worked fine for me in the Meza 1_39 upgrade using Ansible 2.9.27</ref>  <code>ansible-galaxy [delete|import|info|init|install|list|login|remove|search|setup] [--help] [options]</code> == Modules ==
Ansible comes with [https://docs.ansible.com/ansible/modules_by_category.html over 200 modules] that you should get familiar with in order to use the system effectively.
== Example Commands ==There are a bunch of modules in Ansible, like the [https://docs.ansible.com/ansible/mysql_db_module.html MySQL module], the [https://docs.ansible.com/ansible/monit_module.html Monit module], or the [https://docs.ansible.com/ansible/file_module.html File module] and other interesting modules like jabber, mail, sendgrid, dpkg_selections, composer, yum, redhat_subscription, [https://github.com/ansible/ansible-modules-core/blob/devel/cloud/digital_ocean/digital_ocean.py digital ocean], the [https://docs.ansible.com/ansible/authorized_key_module.html authorized_key module] for working with SSH keys, and a whole section of [https://docs.ansible.com/ansible/list_of_system_modules.html system modules].
You can use the '''command module''' (secure but simple) or the '''[https://docs.ansible.com/ansible/shell_module.html shell module]'''. The latter may be useful if you need to run bash explicitly (defaults to /bin/sh); or anytime you need $HOME and redirection. To sanitize any variables passed to the shell module, you should use <nowiki>"{{ var | quote }}" instead of just "{{ var }}"</nowiki> to make sure they don't include evil things like semicolons.  ==Example Commands==Note: control verbosity with <code>-vvvv</code> # <code>ansible --help</code> display help#<code>ansible --version</code> show version info#<code>ansible -c local -i ~/ansible_hosts -m ping all</code> ping all the hosts in the inventory file#<code>ansible '''-m setup ''' wiki.example.com</code> will show you all Use the '''[https://docs.ansible.com/ansible/latest/setup_module.html setup]''' module to gather ansible 'facts' (aka [[ansible_variables]]) about that host.#<code>ansible '''localhost''' -m setup -a 'gather_subset=!all'</code> or look at the localhost# <code>ansible all -m setup -a '''"filter=ansible_distribution*"'''</code> use a filter action to see specific variables#<code>ansible localhost -m setup --tree /tmp/facts</code> store all facts in a file 'tree', based on hostname
#<code>ansible -m debug -a "var=hostvars['wiki.example.com']" localhost</code> gives you the '[[ansible hostvars]]'
# <code>ansible-playbook play1.yml play2.yml</code> Run multiple playbooks#<code>ansible-playbook -i production webservers.yml --tags ntp '''--list-tasks'''</code> confirm what task names would be run if I ran this command and said "just ntp tasks"#<code>ansible-playbook '''--list-tags''' launch.yml</code> see what tags exist in my playbook (the tasks list shows more detail + the tags)#<code>ansible-playbook -i production webservers.yml --limit boston '''--list-hosts'''</code> confirm what hostnames might be communicated with if I said "limit to boston" <ref>Choosing which host(s) to operate on https://docs.ansible.com/ansible/intro_patterns.html</ref># <code>~/bin/ansible/contrib/inventory/digital_ocean.py --list --pretty --api-token TOKEN_HERE</code> use the DO api to list your droplets (dynamic inventory)#<code>ansible-playbook -vvv launch.yml -l wiki.example.com --user=root -e do_name=wiki.example.com '''--start-at-task'''='remove empty wiki schema from database if it already exists'</code> start at a particular point in the task list#<code>php -r 'var_dump(json_decode(file_get_contents("/tmp/facts/localhost"), true));'</code> look at the json with php (or more interesting tools) With Ansible's Jinja2 filters, you can specify the output of a variable to be 'pretty' <nowiki>{{ some_variable | to_nice_json }}</nowiki> ==Variables==
== Variables ==; You have 3 plays in one playbook. Will play 3 be able to reference facts registered in play 1?:: facts, yes, play vars, no: vars associated to the host, persist, vars defined in the play, do not, set_facts, registered vars and gathered facts associate to the host so those do persist for the run
== Playbooks ==
Ansible "[http://docs.ansible.com/playbooks.html Playbooks]" use an easy and descriptive language based on YAML.
==Roles==[https://www.redhat.com/sysadmin/developing-ansible-role 8 steps to developing an Ansible role] (aka when a playbook becomes a re-usable role)  == Targets ==
Ansible can deploy to virtualization environments and public and private cloud environments including VMWare, OpenStack, AWS, Eucalyptus Cloud, KVM, and CloudStack
== Installation ==
The preferred way to [http://docs.ansible.com/intro_installation.html install] is to just <code>git clone</code> the source. Having the source makes it easy to upgrade, and it's self-contained, plus best of all you get all the examples and contribs. However, when I ran my first <code>ansible-playbook digitalocean.yml</code>, I got an error message
<pre>
Traceback (most recent call last):
File "/usr/local/bin/ansible-playbook", line 44, in <module>
import ansible.constants as C
ImportError: No module named ansible.constants
</pre>
Clearly ansible is falling back to the OS installed version. After I ran <code>source ~/bin/ansible/hacking/env-setup</code>, then I was able to run my ansible playbook
==Testing=={{#evu:https://www.youtube.com/watch?v=FaXVZ60o8L8&t=1244s|alignment=right}}  [[File:Ansible linting and testing spectrum.png|thumb|left|The spectrum of testing you can employ in your Ansible deployments]]Jeff Geerling talks about the spectrum of testing you can employ in your Ansible deployments<ref>https://www.youtube.com/live/FaXVZ60o8L8?si=gFoxE-ig5X0psuul&t=1244</ref> #<code>yamllint</code>#<code>ansible-playbook --syntax-check</code>#<code>ansible-lint</code> https://ansible.readthedocs.io/projects/lint/ TLDR; you might want to setup a venv and then pip3 install ansible-lint#molecule test (integration)#<code>ansible-playbook --check</code> (against prod)#parallel infrastructure In development #Use the <tt>debug</tt> module#Use the <tt>fail</tt> module to fail#Use the <tt>assert</tt> module to make assertions (and fail if they don't match) ==Best Practices==Building Ansible Automation Platform execution environments (EE)  *https://www.redhat.com/architect/ansible-execution-environment-tips Using Python 3 *https://docs.ansible.com/ansible/latest/reference_appendices/python_3_support.html*https://docs.ansible.com/ansible/latest/dev_guide/developing_python_3.html *Use tags to organize your Ansible work *Use caching (default is off) to be able to refer to host 'facts' without having to hit each host in a playbook. *Use register of [https://docs.ansible.com/ansible/playbooks_variables.html variables] to create more 'facts'. Results vary from module to module. Use -v to see possible values. *There is an order of precedence with [https://docs.ansible.com/ansible/playbooks_variables.html playbook variables], with role defaults the lowest priority and extra vars the winner. *The array notation is preferred over the dot notation for accessing variables.<br /> <nowiki>{{ ansible_eth0["ipv4"]["address"] }} over {{ ansible_eth0.ipv4.address }}</nowiki> because some keywords in Python would conflict *Reserved words:**hostvars**group_names**groups**environemnt *'''<code>inventory_hostname</code>''' is the name of the hostname as configured in Ansible's inventory host file. '''<code>ansible_hostname</code>''' is the discovered hostname *You can use a variables file to put sensitive data in a different file (one excluded from git).<source lang="yaml">- hosts: all remote_user: root vars: favcolor: blue vars_files: - /vars/top_secret.yml</source> *You can use variables on the command line (and besides key=value pairs, you can use json or yml)<source lang="yaml">--- - hosts: '{{ hosts }}' remote_user: '{{ user }}'  tasks: - ...</source><code>ansible-playbook release.yml --extra-vars "hosts=vipers user=starbuck"</code> *Check [https://www.ansible.com/blog/ansible-performance-tuning Performance Tuning] like enabling <code>pipelining</code> which is off by default. *Truthy values should always be expressed as '''one of <code>[false, true]</code>'''. Although the Ansible docs show that [https://docs.ansible.com/ansible/latest/YAMLSyntax.html#yaml-basics you can use several forms of expression for boolean values], and [http://yaml.org/type/bool.html the YAML spec specifies a fuller range of possibilities] described below, the Ansible documentation now also [https://docs.ansible.com/ansible/latest/reference_appendices/YAMLSyntax.html clarifies that only lowercase 'true' or 'false'] is compatible with [[yamllint]] options. ;YAML boolean values, not Ansible::<syntaxhighlight lang="ebnf">y|Y|yes|Yes|YES|n|N|no|No|NO|true|True|TRUE|false|False|FALSE|on|On|ON|off|Off|OFF</syntaxhighlight> ==Scope==Ansible has 3 main scopes: '''Global''': this is set by config, environment variables and the command line'''Play''': each play and contained structures, vars entries, include_vars, role defaults and vars.'''Host''': variables directly associated to a host, like inventory, facts or registered task outputs Another aspect of scope is <tt>includes</tt> vs. <tt>imports</tt> and loosely speaking, control structures like <tt>loop</tt> and the deprecated <tt>with_items</tt> *https://stackoverflow.com/questions/68863854/iterate-list-within-role-task-provide-each-element-as-vars-to-include-tasks*https://docs.ansible.com/ansible/latest/playbook_guide/playbooks_reuse.html#comparing-includes-and-imports-dynamic-and-static-re-use ==Ansible with VSCode==https://marketplace.visualstudio.com/items?itemName=redhat.ansible ==Ansible with Vagrant==https://docs.ansible.com/ansible/guide_vagrant.html and [[Private:QualityBox/Vagrant]] == Ansible with MediaWiki ==
https://github.com/Orain
I've cloned the '[https://github.com/freephile/ansible-playbook.git ansible-playbook]'
== Ansible with Drupal == * Jeff Geerling (geerlingguy) has his code on github https://github.com/geerlingguy/drupal-vm, and also a website http://www.drupalvm.com/. He's the author of Ansible for DevOps. The only problem I see with his code is that it installs everything from his own 'roles' (individual components) via the sharing site/mechanism called Ansible Galaxy. So, for example, phpMyAdmin comes from https://github.com/geerlingguy/ansible-role-phpmyadmin This is good in that he can make his system work, but it's bad in that you're getting all your bits from him and can't tweak any of it without manually checking each role for the code and instructions behind it so you know what you can set via variables and such. I'd rather see each of these roles contained in the project, community sourced, installed via git.
<pre>
geerlingguy.firewall
</pre>
* on [https://www.digitalocean.com/community/tutorials/how-to-create-an-ansible-playbook-to-automate-drupal-installation-on-ubuntu-14-04 Digital Ocean]
== Ansible in the cloud ==
Ansible has several core modules for working with various [http://docs.ansible.com/list_of_cloud_modules.html cloud providers]. These include
* Amazon* [[Digital Ocean]] http://docs.ansible.com/digital_ocean_module.html* [[Linode]] http://docs.ansible.com/linode_module.html* [[LXC]]
* OpenStack
== Ansible on Fedora ==
The [https://fedoraproject.org/wiki/Fedora_Project_Wiki Fedora Project] uses Ansible in it's Infrastructure team, and they publish their whole setup https://infrastructure.fedoraproject.org/cgit/ansible.git/tree/README
== Ansible Docs ==
Some of the docs pages I've visited
* https://docs.ansible.com/ansible/playbooks_intro.html* https://docs.ansible.com/ansible/intro_inventory.html* http://docs.ansible.com/playbooks_best_practices.html* http://docs.ansible.com/playbooks_loops.html* https://docs.ansible.com/ansible/playbooks_conditionals.html* https://docs.ansible.com/ansible/playbooks_startnstep.html* https://docs.ansible.com/ansible/playbooks_roles.html#task-include-files-and-encouraging-reuse* http://docs.ansible.com/YAMLSyntax.html* https://docs.ansible.com/ansible/become.html* https://docs.ansible.com/ansible/debug_module.html* https://docs.ansible.com/ansible/playbooks_debugger.html (<code>strategy:debug</code>)* https://docs.ansible.com/ansible/playbooks_conditionals.html#sts=The When Statement%C2%B6  ==Controlling Whitespace in Jinja2 Templates==See [[Controlling whitespace in Jinja2 templates]] ==Ansible References==
*http://tjelvarolsson.com/blog/taking-the-effort-out-of-server-configuration-using-ansible/
*http://tjelvarolsson.com/blog/how-to-create-automated-and-reproducible-work-flows-for-installing-scientific-software/ < with Vagrant
*http://jpmens.net/2012/06/06/configuration-management-with-ansible/
*[http://jinja.pocoo.org/docs/dev/ Jinja] - the template engine for Ansible
*[https://cheat.readthedocs.io/en/latest/ansible/index.html Dan's Cheat Sheets]
== Ansible References To Do ==* http://tjelvarolsson.com/blog/taking-the-effort-out-of-server-configuration-using-ansible/* http://tjelvarolsson.com/blog/how-to-create-automated-and-reproducible-work-flows-for-installing-scientific-software/ < with Vagrant* http://jpmens.net/2012/06/06/configuration-management-with-ansible/* [http://jinja.pocoo.org/docs/dev/ Jinja] - the template engine for Ansible
# Follow and learn from Jeff Geerling's Drupal site https://github.com/geerlingguy/jeffgeerling-com because his techniques embody best practices for PHP, Drupal, Docker, Ansible, etc. In episode 12 of Ansible 101 - Real-world Ansible Playbooks [https://www.youtube.com/live/_QZr4xKhir4?si=LOyBibByqdmLb7M6&t=1107 here] he discusses his Drupal playbook and the 'deploy' tag. But sadly the playbooks are private (Midwestern Mac infrastructure), so you'll have to read the screen to emulate it exactly. The closest I found was https://github.com/geerlingguy/ansible-awx-varnish-php-app/blob/master/main.yml
# Add info (separate page) about the Ansible clone of the Ruby deployment system 'Capistrano' called 'Anistrano'
## https://www.oliverdavies.uk/talks/deploying-php-ansible-ansistrano
## https://github.com/ansistrano/deploy
{{References}}
[[Category:Virtualization]]
[[Category:Configuration Management]]
[[Category:DevOps]]

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