ANSIBLE

Ansible is an open-source automation tool used for configuration management, application deployment, and task automation. It is designed to be simple to set up and use, yet powerful enough to manage complex deployments and IT environments. Ansible is a software tool that provides simple but powerful automation for cross-platform computer support. It is primarily intended for IT professionals, who use it for application deployment, updates on workstations and servers, cloud provisioning, configuration management, intra-service orchestration, and nearly anything a systems administrator or devops professionals does on a weekly or daily basis. Ansible doesn't depend on agent software and has no additional security infrastructure, so it's easy to deploy.

How Ansible works

In Ansible, there are two categories of computers: the control node and managed nodes. The control node is a computer that runs Ansible. There must be at least one control node, although a backup control node may also exist. A managed node is any device being managed by the control node.

Ansible works by connecting to nodes (clients, servers, or whatever you're configuring) on a network, and then sending a small program called an Ansible module to that node. Ansible executes these modules over SSH and removes them when finished. The only requirement for this interaction is that your Ansible control node has login access to the managed nodes. SSH keys are the most common way to provide access, but other forms of authentication are also supported.

 

Basic Concepts:

1.      Playbooks:

o    Playbooks are YAML files where you define your automation tasks. Each playbook consists of one or more plays, and each play applies a set of tasks to a group of hosts.

2.      Inventory:

o    The inventory is a file that defines the hosts and groups of hosts upon which Ansible will operate. It can be a static file or dynamically generated.

3.      Tasks:

o    Tasks are the actions executed by Ansible modules within a play. Each task typically calls a module to perform a specific function

1.      Roles:

o    Roles are a way to organize playbooks and tasks into reusable components. Each role can include variables, tasks, files, templates, and handlers.

2.      Variables:

o    Variables are used to store values that can be reused throughout playbooks and roles. They make playbooks more flexible and easier to maintain.

3.      Handlers:

o    Handlers are similar to tasks but are only run when notified. They are often used to restart services after a configuration change.

How Ansible Works:

1. Define Inventory:
• Create an inventory file listing all the hosts you want to manage.
2. Write Playbooks:
• Write playbooks to define the tasks and configurations to be applied to the hosts.
3. Run Playbooks:
• Execute the playbooks using the ansible-playbook command to apply the configurations to the managed hosts.

 

Ansible Simplified

In layman terms, Ansible is a tool that helps you automate tasks on multiple computers. It's like having a remote control for your computers, allowing you to do things like installing software, updating settings, and starting or stopping services without having to manually log into each computer and do it yourself.

Here’s a simple analogy:

Ansible as a Remote Control for Your Computers:

1. Imagine You Have Multiple Computers:
• Let’s say you have a bunch of computers, and you need to install a program on all of them. Doing it manually on each one would take a lot of time.
2. Using a Remote Control:
• Instead of going to each computer, you use a remote control (Ansible) to send instructions to all of them at once. You write down what you want to do (like installing a program) in a simple script.
3. Script as a Set of Instructions:
• This script, called a playbook, is written in plain English-like language so it’s easy to understand. It lists all the steps that need to be done.
4. Sending Instructions:
• With one click, Ansible sends these instructions to all the computers. It uses a built-in communication method (like SSH) to connect to each computer and run the instructions.
5. No Special Setup Needed:
• The computers don’t need any special software installed to receive these instructions, just a way to communicate (like SSH, which is usually already set up).
6. Consistency and Efficiency:
• This way, you ensure that all your computers are set up exactly the same way without having to repeat the process manually, saving you a lot of time and effort.