What is an Ansible Playbook?

An Ansible® Playbook is a blueprint of automation tasks, which are IT actions executed with limited manual effort across an inventory of IT solutions. Playbooks tell Ansible what to do to which devices.

Instead of manually applying the same action to hundreds or thousands of similar technologies across IT environments, executing a playbook automatically completes the same action for the specified type of inventory—such as a set of routers. Playbooks also serve as frameworks of prewritten code that developers can use ad-hoc or as a starting template.

Playbooks are regularly used to automate IT infrastructure—such as operating systems and Kubernetes platforms—networks, security systems, and code repositories like GitHub. IT staff can use playbooks to program applications, services, server nodes, and other devices, without the manual overhead of creating everything from scratch.

And playbooks—as well as the conditions, variables, and tasks within them—can be saved, shared, or reused indefinitely. This makes it easier for IT teams to codify operational knowledge and ensure that the same actions are performed consistently.

Ansible Playbooks are lists of tasks that automatically execute for your specified inventory or groups of hosts. One or more Ansible tasks can be combined to make a play—an ordered grouping of tasks mapped to specific hosts—and tasks are executed in the order in which they are written. A playbook can include 1 or more plays as well as Ansible Roles—bundles of tasks and associated automation assets that can be run in multiple plays or reused across playbooks.

Tasks are executed by modules, each of which performs a specific task in a playbook. A module contains metadata that determines when and where a task is executed, as well as which user executes it. There are thousands of Ansible modules that perform all kinds of IT tasks, such as:

Ansible is capable of communicating with many different device classifications, from cloud-based REST APIs, to Linux and Windows systems, networking hardware, and much more. This is a sample of 2 Ansible modules automatically updating 2 types of servers:

---
- name: Update web servers
  hosts: webservers
  become: true
 
  tasks:
    - name: Ensure apache is at the latest version
      ansible.builtin.yum:
        name: httpd
        state: latest
    - name: Write the apache config file
      ansible.builtin.template:
        src: /srv/httpd.j2
        dest: /etc/httpd.conf
        mode: "0644"
 
- name: Update db servers
  hosts: databases
  become: true
 
  tasks:
    - name: Ensure postgresql is at the latest version
      ansible.builtin.yum:
        name: postgresql
        state: latest
    - name: Ensure that postgresql is started
      ansible.builtin.service:
        name: postgresql
        state: started

The playbook contains 2 plays: 

• The first checks whether or not web server software is up to date and runs the update if necessary.
• The second checks whether or not database server software is up to date and runs the update if necessary.

Ansible uses the YAML syntax. Depending on whom you ask, YAML stands for yet another markup language or YAML ain’t markup language (a recursive acronym). There are also 2 different, but perfectly acceptable YAML file extensions: .yaml or .yml. 

There are 2 ways of using Ansible Playbooks: from the command line interface (CLI) or using the Red Hat® Ansible Automation Platform’s push-button deployments.

Because YAML is a human-readable language, IT professionals with specific domain expertise—like in network, security, or cloud—can create playbooks without having to learn a complicated coding language.

Red Hat Ansible Automation Platform is a unified platform that can automate full processes across your IT domains for a variety of use cases—including infrastructure, hybrid cloud, security, and networks, all the way to edge locations. Ansible Automation Platform includes all the tools needed to implement enterprise-wide automation, including an event-driven solution, playbooks, and analytics. And it allows your teams to centralize and control your IT infrastructure with a visual dashboard, role-based access control, and other features that will help reduce operational complexity.

With a Red Hat subscription, you get certified, supported content from Red Hat and our partners, access to hosted management services, and life cycle technical support to scale automation across your organization. And you’ll get expert knowledge gained from our success with thousands of customers.

The introduction of Red Hat Ansible Lightspeed with IBM watsonx Code Assistant makes Ansible even more accessible to beginners and helps experienced automation teams learn, create, and maintain Ansible Automation Platform content more efficiently. This generative AI service accepts prompts entered by a user and then interacts with IBM watsonx foundation models to produce code recommendations built on Ansible best practices—helping you convert subject matter expertise into trusted, reliable Ansible code that scales across teams and domains.