What is an Ansible Playbook? How to Write a Simple Ansible Playbook?

We are living in a technologically driven world today. One of the key things to play a big part is automation. Every big and organization is dependent on it to help move forward. Thus, the need for reliable automation tools has increased. One such tool is Ansible, a name that is trusted throughout the tech world.

In order to handle such an extensively used tool, experts are needed. With Ansible training and certification from the right institute, you can become this expert. There are a lot of things you need to learn about Ansible if you want to take it up as your career. There are a lot of questions that need to be answered prior to moving ahead in this direction.

What is Ansible? What is an Ansible Playbook? How to write a simple Ansible playbook? What is the scope for career enhancement after completing Ansible training and certification course? Everything you want to know around Ansible will get answered here. This blog is going to give you answers. And the ones that you do not get here, will be answered by experts at Grras Solutions.

In order to get to writing a simple Ansible playbook, you need to begin with the first step. And that first step is knowing what is Ansible. Once you know about it, moving towards the next stage becomes easier. So, let us begin, one peel at a time.

 

Ansible – An Introduction

In order to fully comprehend anything about Ansible playbook, you need to start with the basics. Thus, here is a simple introduction to Ansible to get you started.

Ansible is a widely famous modern configuration management tool. The purpose of this tool is to aid in carrying out the task of setting up as well as maintaining remote servers. You can control one or even hundreds of systems, all from a central location with the aid of ad hoc commands or playbooks. It offers a minimalist design with the intention of having users up and running quickly.

With ad hoc commands, the user can run one-off task on the servers that are registered within their inventory file. Playbooks, on the other hand, allows the automation of a sequence of tasks to set up servers as well as deploy applications to remote servers. A playbook may contain more than one plays.

It is an open-source automation tool. There are many things it helps in including configuration, provisioning, application deployment, and intra-service orchestration. One of its biggest uses is in DevOps, where it eliminates repetitive, time-consuming tasks. This gives teams the chance to divert their focus on tasks that require more of their attention and strategic urgency.

An Ansible playbook is a key aspect of Ansible. It is also the core element of every Ansible configuration. Let us look at a deeper explanation of what is an Ansible playbook and how to write a simple Ansible playbook.

 

What is an Ansible Playbook?

In order to understand Ansible playbooks, you need to begin with Ansible code. Ansible code is a systematized collection of various scripts that define the work of a server configuration. And Ansible playbooks are files where users are able to write this Ansible code. The code defines layers of steps to be followed in a general policy or an IT process to enforce your remote systems.

Playbooks comprise of one or many plays that run in a set order. And a play is a set of tasks that are run against hosts picked from the users’ inventory. Plays simply give away the work that needs to be done. Every single play comprises of a list of tasks that needs to be completed and or asset of hosts that needs to be configured.

It is important to note that is no concept of a standardised play. Each play must be written by an administrator.

Playbooks use YAML. It is a human-readable data serialization language. The term YAM is a recursive acronym as its stands for ‘YAML Ain’t Markup Language.’

 

Ad-Hoc Commands – A Word

Ad-hoc commands aid in automating singular tasks on one or multiple managed nodes. This is done by using the /usr/bin/ansible command-line tool.

Ad-hoc tools are easy and fast to create. However, they are not reusable. Thus, they are only suitable for tasks that do not need to be performed often.

Many ad-hoc command concepts are applicable to playbooks as well. Hence, it is advisable to master these commands.

 

How to Write a Simple Ansible Playbook?

Ansible playbooks can be as big or small as you want them to be. It does not necessarily have to fit into any specific dimensions. In fact, these can get quite complex and large. Now, it does not matter whether you are looking to make a gigantic one or a simple, sweet one. There are certain things you need to do to bring it together.

Here is how you can write an Ansible playbook.

You should know that all playbooks are segregated into the same standard sections.

• Each playbook begins with three hyphens - - -
• Host

The first section to come is the host section. It defines the target machines wherein this playbook will be run. The information is derived on the basis of the Ansible inventory file. Thus, we can also say the host section is a list of devices.

• Variable

The next section is variable but is totally optional. It consists of all the variable that the playbook might require. If the user feels the need for it to be there, it can vary from small to large.

• Tasks

The next section that comes forth is the task section. It is here that all the tasks that must be run by the target machine is listed. It also specifies the use of the Modules. Every task is given a name and a small description describing the task’s purpose. It gets listed when the playbook runs.

• End

It should be noted that most playbooks are ended with three periods.     . . .

 

Here are some key pointers to keep in mind when you set out to work with Ansible playbooks.

• Playbooks are written in the YAML format. These have a .yml file extension
• The $ ansible-playbook --syntax-check command is used for checking the playbook for syntax errors
• The $ ansible-playbook command is used for running a playbook
• It is important to include whitespaces. When you put blank lines in between every block or task, scanning the playbook becomes much easier
• Including state is recommended. While it is not mandatory, but it does offer clarity. Thus, using state settings such as ‘state=absent’ or ‘state=present’ will come handy
• Creating lists is definitely a good way to go. This will help you in defining elements within your playbook variables. The ‘-’ symbol is used for creating a list
• Employing comments will help users understand what a task is doing, how it is doing it, and why is it doing it. After all, some instances simply require more information
• Just like including a state is recommended but not mandatory, so is naming your tasks. It is optional but will definitely come in handy at some point. The best way to go about it is to pick names that go along well with what each task does

Acing the art of writing an Ansible playbook will take some time and a lot of practice. However, if you just keep following these sections and the notes we have given afterwards, then you will be good to go.

Now that you know about Ansible, Ansible playbooks, and how to write them, it must be answered that what are its uses. After all, you should know why you are going why you are going. Right? So, let us begin!

 

Uses of Ansible Playbooks

There are a lot of places where Ansible playbooks come to be used. They run various tasks, define variables, deployment steps, and configurations, and assign roles. Playbooks can be considered equivalent to instruction manuals.

Ansible playbooks can also be employed for managing configurations of and deployments to remote machines. Playbooks can also sequence a multi-tiered rollout employing rolling updates. Thus, they help in launching tasks both synchronously or asynchronously, as per the need.

In short, Ansible playbooks are known to aid users in easily controlling various machines. They also enable all affected units to act in harmony. For DevOps professionals, Ansible is a knowledge that will help them go the long way in their career.

 

Conclusion

One of the things to keep in your mind is to enroll with the right Ansible training and certification course. Once you complete it, your future will start to look bright as you will come face-to-face with numerous additional opportunities.

It is best to get started today when the number of job openings is higher than the number of qualified professionals to claim them. So, begin now with the right institute and the right course.