Ansible (software)

Ansible is an open-source software provisioning, configuration management, and application-deployment tool enabling infrastructure as code.[2] It runs on many Unix-like systems, and can configure both Unix-like systems as well as Microsoft Windows. It includes its own declarative language to describe system configuration. Ansible was written by Michael DeHaan and acquired by Red Hat in 2015. Ansible is agentless, temporarily connecting remotely via SSH or Windows Remote Management (allowing remote PowerShell execution) to do its tasks.

1525 companies reportedly use Ansible in their tech stacks, including LaunchDarkly, Tokopedia, and ViaVarejo.

· LaunchDarkly.

· Tokopedia.

· ViaVarejo.

· trivago.

· Revolut.

· Alibaba Travels.

· Typeform.

Ansible Terms:

• Controller Machine: The machine where Ansible is installed, responsible for running the provisioning on the servers you are managing.
• Inventory: An initialization file that contains information about the servers you are managing.
• Playbook: The entry point for Ansible provisioning, where the automation is defined through tasks using YAML format.
• Task: A block that defines a single procedure to be executed, e.g. Install a package.
• Module: A module typically abstracts a system task, like dealing with packages or creating and changing files. Ansible has a multitude of built-in modules, but you can also create custom ones.
• Role: A pre-defined way for organizing playbooks and other files in order to facilitate sharing and reusing portions of a provisioning.
• Play: A provisioning executed from start to finish is called a play. In simple words, execution of a playbook is called a play.
• Facts: Global variables containing information about the system, like network interfaces or operating system.
• Handlers: Used to trigger service status changes, like restarting or stopping a service.

Advantages Of Using Ansible

Simple

Agentless

Powerful & Flexible

Efficient

What Ansible Can Do?

Provisioning

Configuration Management:

Application Deployment

Security and Compliance:

Orchestration

The Ansible Automation engine consists of:

• Inventories: Ansible inventories are lists of hosts (nodes) along with their IP addresses, servers, databases etc. which needs to be managed. Ansible then takes action via a transport — SSH for UNIX, Linux or Networking devices and WinRM for Windows system.
• APIs: APIs in Ansible are used as transport for Cloud services, public or private.
• Modules: Modules are executed directly on remote hosts through playbooks. The modules can control system resources, like services, packages, or files (anything really), or execute system commands. Modules do it by acting on system files, installing packages or making API calls to the service network. There are over 450 Ansible-provided modules that automate nearly every part of your environment. For e.g.
• Cloud Modules like cloudformation which creates or deletes an AWS cloud formation stack;
• Database modules like mssql_db which removes MYSQL databases from remote hosts.
• Plugins: Plugins allows to execute Ansible tasks as a job build step. Plugins are pieces of code that augment Ansible’s core functionality. Ansible ships with a number of handy plugins, and you can easily write your own. For example,
• Action plugins are front ends to modules and can execute tasks on the controller before calling the modules themselves.
• Cache plugins are used to keep a cache of ‘facts’ to avoid costly fact-gathering operations.
• Callback plugins enable you to hook into Ansible events for display or logging purposes.

There are a few more components in Ansible Architecture which are explained below:

Networking: Ansible can also be used to automate different networks. Ansible uses the same simple, powerful, and the agentless automation framework IT operations and development are already using. It uses a data model (a playbook or role) that is separate from the Ansible automation engine that easily spans different network hardware.

Hosts: The hosts in the Ansible architecture are just node systems which are getting automated by Ansible. It can be any kind of machine — Windows, Linux, RedHat etc.

Playbooks: Playbooks are simple files written in YAML format which describes the tasks to be executed by Ansible. Playbooks can declare configurations, but they can also orchestrate the steps of any manual ordered process, even if it contains jump statements. They can launch tasks synchronously or asynchronously.

CMDB : It is a repository that acts as a data warehouse for IT installations. It holds data relating to a collection of IT assets (commonly referred to as configuration items (CI)), as well as to describe relationships between such assets.

Cloud: It is a network of remote servers hosted on the Internet to store, manage, and process data, rather than a local server. You can launch your resources and instances on cloud and connect to your servers.

How NASA is using Ansible:

Ansible Tower provided with a dashboard which provided the status summary of all hosts and jobs which allowed NASA to group all contents and manage access permissions across different departments. It also helped to split up the organization by associating content and control permission for groups as well.

Ansible Tower is a web-based interface for managing Ansible. One of the top items in Ansible users’ wishlists was an easy-to-use UI for managing quick deployments and monitoring one’s configurations. Ansible management came up with Ansible Tower in response.

Further, Ansible divided the tasks among teams by assigning various roles. It managed the clean up of old job history, activity streams, data marked for deletion and system tracking info. Refer to the diagram below to understand how Ansible has simplified the work of NASA.