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How to use Ansible Galaxy

Ansible Galaxy is a repository for Ansible Roles that are available to drop directly into your Playbooks to streamline your automation projects.
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Galaxy

Messier 104 (The Sombrero Galaxy): NASA and the Hubble Heritage Team (STScI/AURA)

Ansible is a multiplier, a tool that automates and scales infrastructure of every size. It is considered to be a configuration management, orchestration, and deployment tool. It is easy to get up and running with Ansible. Even a new sysadmin could start automating with Ansible in a matter of a few hours.

Ansible automates using the SSH protocol. The control machine uses an SSH connection to communicate with its target hosts, which are typically Linux hosts. If you’re a Windows sysadmin, you can still use Ansible to automate your Windows environments using WinRM as opposed to SSH. Presently, though, the control machine still needs to run Linux.

As a new sysadmin, you might start with just a few playbooks. But as your automation skills continue to grow, and you become more familiar with Ansible, you will learn best practices and further realize that as your playbooks increase, using Ansible Galaxy becomes invaluable.

In this article, you will learn a bit about Ansible Galaxy, its structure, and how and when you can put it to use.

What Ansible does

Common sysadmin tasks that can be performed with Ansible include patching, updating systems, user and group management, and provisioning. Ansible presently has a huge footprint in IT Automation—if not the largest presently—and is considered to be the most popular and widely used configuration management, orchestration, and deployment tool available today.

One of the main reasons for its popularity is its simplicity. It’s simple, powerful, and agentless. Which means a new or entry-level sysadmin can hit the ground automating in a matter of hours. Ansible allows you to scale quickly, efficiently, and cross-functionally.

Create roles with Ansible Galaxy

Ansible Galaxy is essentially a large public repository of Ansible roles. Roles ship with READMEs detailing the role’s use and available variables. Galaxy contains a large number of roles that are constantly evolving and increasing.

Galaxy can use git to add other role sources, such as GitHub. You can initialize a new galaxy role using ansible-galaxy init, or you can install a role directly from the Ansible Galaxy role store by executing the command ansible-galaxy install <name of role>.

Here are some helpful ansible-galaxy commands you might use from time to time:

  • ansible-galaxy list displays a list of installed roles, with version numbers.

  • ansible-galaxy remove <role> removes an installed role.

  • ansible-galaxy info provides a variety of information about Ansible Galaxy.

  • ansible-galaxy init can be used to create a role template suitable for submission to Ansible Galaxy.

To create an Ansible role using Ansible Galaxy, we need to use the ansible-galaxy command and its templates. Roles must be downloaded before they can be used in playbooks, and they are placed into the default directory /etc/ansible/roles. You can find role examples at https://galaxy.ansible.com/geerlingguy:

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Installing the role HAProxy from geerlingguy.

Create collections

While Ansible Galaxy has been the go-to tool for constructing and managing roles, with new iterations of Ansible you are bound to see changes or additions. On Ansible version 2.8 you get the new feature of collections.

What are collections and why are they worth mentioning? As the Ansible documentation states:

Collections are a distribution format for Ansible content. They can be used to package and distribute playbooks, roles, modules, and plugins.

Collections follow a simple structure:

collection/
├── docs/
├── galaxy.yml
├── plugins/
│ ├──  modules/
│ │ └──  module1.py
│ ├──  inventory/
│ └──  .../
├── README.md
├── roles/
│ ├──  role1/
│ ├──  role2/
│ └──  .../
├── playbooks/
│ ├──  files/
│ ├──  vars/
│ ├──  templates/
│ └──  tasks/
└──  tests/
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Creating a collection skeleton.
Creating a collection skeleton.

The ansible-galaxy-collection command implements the following commands. Notably, a few of the subcommands are the same as used with ansible-galaxy:

  • init creates a basic collection skeleton based on the default template included with Ansible, or your own template.

  • build creates a collection artifact that can be uploaded to Galaxy, or your own repository.

  • publish publishes a built collection artifact to Galaxy.

  • install installs one or more collections.

In order to determine what can go into a collection, a great resource can be found here.

Conclusion

Establish yourself as a stellar sysadmin with an automation solution that is simple, powerful, agentless, and scales your infrastructure quickly and efficiently. Using Ansible Galaxy to create roles is superb thinking, and an ideal way to be organized and thoughtful in managing your ever-growing playbooks.

The only way to improve your automation skills is to work with a dedicated tool and prove the value and positive impact of automation on your infrastructure.

Topics:   Ansible   Automation  
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Tonya Brown

Tonya Brown, is a Scrum/Agile Practitioner and Technical Product Manager working with DevOps and Software Development teams.  She is an avid writer and speaker with a diverse background in Scrum, Agile, digital product management, Linux systems engineering, management and deployment of DevOps sol More about me

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