Tech Tutorial: Use Roles and Ansible Content Collections #

Introduction #

In the domain of automation and configuration management, Ansible is a pivotal tool used extensively to deploy and manage applications in an efficient and scalable manner. In this tutorial, we will explore how to enhance your Ansible capabilities by leveraging Ansible Content Collections and Roles. These features allow for more modular, reusable, and maintainable code structures within your automation strategies. This is especially relevant for those preparing for the Red Hat Certified Engineer (RHCE) exam, where proficiency in these areas is essential.

Step-by-Step Guide #

Prerequisites #

Before we dive into the practical steps, ensure that your system is set up with:

• A RHEL 8 system
• Ansible installed (Ansible Core 2.9 or later is recommended for full support of Collections)

To install Ansible on RHEL 8, you can use the following command:

sudo dnf install ansible

1. Understanding Ansible Content Collections #

Ansible Collections are a distribution format for Ansible content that can include playbooks, roles, modules, and plugins. They are designed to help you organize and scale your Ansible content more effectively.

2. Installing Ansible Collections #

To install an Ansible Collection from Ansible Galaxy, use the ansible-galaxy command. For instance, to install the community.general collection, you would use:

ansible-galaxy collection install community.general

To install a specific version or source it from a private Galaxy server, you can specify it in the command:

ansible-galaxy collection install community.general:1.3.0 --server http://myprivategalaxy.example.com

3. Using Collections in a Playbook #

Once a collection is installed, you can use the modules, roles, and other content it includes in your playbooks. For example, here’s how you can use the ping module from the community.general collection:

---
- name: Test connection
  hosts: all
  gather_facts: no

  tasks:
    - name: Ping test
      community.general.ping:

4. Understanding and Using Ansible Roles #

Roles in Ansible allow you to automate the creation of reusable components. They can be used to encapsulate and organize your automation content.

Creating a Role #

To create a role, use the ansible-galaxy command:

ansible-galaxy init role_name

This creates a role directory structure under a directory named role_name.

Example Role Structure #

role_name/
├── defaults
│   └── main.yml
├── handlers
│   └── main.yml
├── meta
│   └── main.yml
├── README.md
├── tasks
│   └── main.yml
├── tests
│   ├── inventory
│   └── test.yml
└── vars
    └── main.yml

Using a Role in a Playbook #

Here’s an example of how to use a created role in a playbook:

---
- name: Apply the role
  hosts: all
  roles:
    - role_name

5. Putting It All Together #

Now, let’s combine what we’ve learned about Collections and Roles in a practical example:

---
- name: Web server setup
  hosts: web_servers
  gather_facts: yes

  collections:
    - community.general

  roles:
    - role_name

  tasks:
    - name: Ensure Apache is at the latest version
      community.general.yum:
        name: httpd
        state: latest

Conclusion #

Using Ansible Roles and Content Collections can significantly streamline and enhance your automation workflows. By modularizing your tasks and utilizing community-driven resources, you can achieve more maintainable and scalable infrastructure automation. This knowledge not only aids in real-world scenarios but is also essential for those preparing for the RHCE exam. Implement these strategies to develop more robust and effective automation solutions.