What is Ansible?

• Agentless Architecture: Ansible operates without the need for agents on managed nodes. It connects via SSH or WinRM for Windows systems, allowing seamless communication and reducing system overhead.
• Ansible for ad-hoc commands: You can also use Ansible to run ad-hoc commands, which automate a single task on one or more managed nodes. To do this, you will need to run a command or call a module directly from the command line. No playbook is used, and ad-hoc commands are not reusable. This is fine for a one-time task, but anything more frequent or complex will require the use of an Ansible Playbook.
• Playbooks and Modules: Ansible uses YAML-based Playbooks, which describe the desired state of systems or configurations. Modules, small units of code, are used to perform specific tasks like installing software, managing files, or configuring services.
• Idempotent Operations: Ansible ensures that operations are idempotent, meaning applying the same configuration multiple times results in the same outcome, reducing the risk of unintended changes.
• Orchestration and Configuration Management: It facilitates orchestration of complex tasks and configuration management across multiple servers, ensuring consistency and efficiency in managing infrastructure.
• Reusability: Supports modular and reusable playbooks and roles, enabling the creation of standardized configurations and the reuse of automation code across projects.
• Extensibility and Integration: Ansible integrates with various cloud providers, networking devices, and third-party tools, allowing for a broad range of automation scenarios.
• Community and Ecosystem: It has a vibrant community contributing modules, playbooks, and support, making it easier to adopt and use Ansible for different use cases.

Key Ansible terms:

• Playbook: A YAML file defining a series of tasks to be executed. Playbooks describe the desired state of the system and use modules to achieve that state.
• Task: An action or unit of work defined within a playbook. Tasks typically involve invoking modules to perform specific actions like installing software, copying files, restarting services, etc.
• Module: A discrete unit of code that carries out specific tasks on managed nodes. Modules are invoked by Ansible to perform actions like managing packages, files, users, services, and more.
• Inventory: A file (often in INI or YAML format) containing a list of managed nodes (servers, devices, etc.) that Ansible manages. It organizes these nodes into groups and assigns variables to them.
• Play: A combination of one or more roles and tasks that work together to achieve a specific objective within a playbook.
• Role: A reusable and self-contained set of tasks, variables, and configurations. Roles are used to organize and package tasks for easier reuse across multiple playbooks.
• Handler: A specific type of task that is only executed when notified by another task. Handlers are commonly used to restart services or perform other actions triggered by changes.
• Facts: System information collected by Ansible from managed nodes, such as network settings, hardware details, OS information, etc. These facts can be used in playbooks for conditional execution or dynamic configurations.