Introduction
Ansible is a popular IT automation engine that automates tasks that are either cumbersome or repetitive or complex like configuration management, cloud provisioning, software deployment, and intra-service orchestration.
Ansible is used for the multi-tier deployments and it models all of IT infrastructure into one deployment instead of handling each one separately. There are no agents and no custom security architecture is required to be used in the Ansible architecture. The deployment is simple plain English like language that is used in Ansible called YAML which stands for “YAML Ain’t Markup Language.”
To work with Ansible is very easy; it pushes out small programs called “Ansible Modules” to your nodes to connect. It can deploy and connect using the SSH agent to execute the modules and then removes it when finished. There are no servers, daemons or databases required these modules can reside anywhere in the machines. You need to work with any text editor or terminal programs and along with a version control system to manage the changes in the content. Ansible has over 750 modules built into it.
In Ansible the passwords are supported, However, you can use SSH keys with the ssh-agents as one of the methods to work with Ansible. You can create any user account and the root user is required. To configure what machines can access which hosts there is a module called “authorized_key”.
You can add machines to the Ansible in a simple text format and manage your inventory. It can use the inventory and variable information from other sources such as Rackspace, EC2, and Openstack, etc.
If you need to write your code then also you can use Ansible in languages such as Python, Ruby, and Bash, etc which return JSON. You can write your modules, API, and Plugins.
Playbooks are the simple and powerful automation language used to orchestrate multiple infrastructures in one goes. This can be done in Ansible.
Why use Ansible for DevOps?
With ever-increasing complex IT environments that often need maintenance, updates, scaling-up activities, keeping up-to-date of everything manually is a burden and a daunting task. The automation simplifies complex tasks using tools like Ansible, allowing developers, operations people, and system admins to concentrate on the tasks that add value to the organization.
Ansible is the right choice for many reasons and processes, starting with configuration management, application deployment, orchestration, provisioning, security and compliance. Using Ansible, applications can be defined and managed from the development stage to production. It supports DevOps teams in managing the infrastructure and interaction of configurations and it helps to automate and manage processes.
Now let’s talk a bit about the pieces that make up the Ansible environment.
1. Modules
Modules are like small programs that Ansible pushes out from a control machine to all the nodes or remote hosts. The modules are executed using playbooks (see below), and they control things such as services, packages, and files. Ansible executes all the modules for installing updates or whatever the required task is, and then removes them when finished. Ansible provides more than 450 modules for everyday tasks.
2. Plugins
As you probably already know from many other tools and platforms, plugins are extra pieces of code that augment functionality. Ansible comes with a number of its plugins, but you can write your own as well. Action, cache, and callback plugins are three examples.
3. Inventories
All the machines you’re using with Ansible (the control machine plus nodes) are listed in a single simple file, along with their IP addresses, databases, servers, and so on. Once you register the inventory, you can assign variables to any of the hosts using a simple text file. You can also pull inventory from sources like EC2 (Amazon Elastic Compute Cloud).
4. Playbooks
Ansible playbooks are like instruction manuals for tasks. They are simple files written in YAML, which stands for YAML Aren’t Markup Language, a human-readable data serialization language. Playbooks are really at the heart of what makes Ansible so popular is because they describe the tasks to be done quickly and without the need for the user to know or remember any particular syntax. Not only can they declare configurations, but they can orchestrate the steps of any manually ordered task, and can execute tasks at the same time or at different times.
5. APIs
Various APIs (application programming interfaces) are available so you can extend Ansible’s connection types (meaning more than just SSH for transport), callbacks, and more.
Conclusion
Ansible is a simple but powerful configuration management and orchestration tool. Ansible is mainly used for the automation of cross-platform computer support tasks. It is fundamentally intended for IT professionals, who use it for configuration management, cloud provisioning, application deployment, intra-service orchestration, updates on workstations and servers, and nearly for anything a systems administrator does on a day-to-day basis. Ansible doesn’t depend on agent software and, most importantly, no additional custom security infrastructure, so this makes it easy to deploy. It uses a straightforward language (YAML, in the form of Ansible Playbooks) that allows people to use it to describe automation jobs, and this way, it’s easy to use.