Ansible's goals are foremost those of simplicity and maximum ease of use. It also has a strong focus on security and reliability, featuring a minimum of moving parts, usage of Open SSH for transport (with an accelerated socket mode and pull modes as alternatives), and a language that is designed around auditability by humans -- even those not familiar with the program.
We believe simplicity is relevant to all sizes of environments and design for busy users of all types -- whether this means developers, sysadmins, release engineers, IT managers, and everywhere in between. Ansible is appropriate for managing small setups with a handful of instances as well as enterprise environments with many thousands.
Ansible manages machines in an agentless manner. There is never a question of how to
upgrade remote daemons or the problem of not being able to manage systems because daemons are uninstalled. As OpenSSH is one of the most peer reviewed open source components, the security exposure of using the tool is greatly reduced. Ansible is decentralized -- it relies on your existing OS credentials to control access to remote machines; if needed it can easily connect with Kerberos, LDAP, and other centralized authentication management systems.
This documentation covers the current released version of Ansible (1.4.3) and also some development version features (1.5). For recent features, in each section, the version of Ansible where the feature is added is indicated. AnsibleWorks releases a new major release of Ansible approximately every 2 months. The core application evolves somewhat conservatively, valuing simplicity in language design and setup, while the community around new modules and plugins being developed and contributed moves very very quickly, typically adding 20 or so new modules in each release.
Before we dive into the really fun parts -- playbooks, configuration management, deployment, and orchestration, we'll learn how to get Ansible installed and some basic concepts. We'll go over how to execute ad-hoc commands in parallel across your nodes using /usr/bin/ansible. We'll also see what sort of modules are available in Ansible's core (though you can also write your own, which we'll also show later).
Playbooks are Ansible's configuration, deployment, and orchestration language. They can describe a policy you want your remote systems to enforce, or a set of steps in a general IT process.
At a basic level, playbooks can be used to manage configurations of and deployments to remote machines. At a more advanced level, they can sequence multi-tier rollouts involving rolling updates, and can delegate actions to other hosts, interacting with monitoring servers and load balancers along the way.
It is recommended to look at `Example Playbooks <https://github.com/ansible/ansible-examples>`_ while reading along with the playbook documentation. These illustrate best practices as well as how to put many of the various concepts together.
`AnsibleWorks <http://ansibleworks.com>`_, who also sponsors the Ansible community, also produces 'AWX', which is a web-based solution that makes Ansible even more easy to use for IT teams of all kinds. It's designed to be the hub for all of your automation tasks.
AWX allows you to control access to who can access what, even allowing sharing of SSH credentials without someone being able to transfer those credentials. Inventory can be graphically managed or synced with a wide variety of cloud sources. It logs all of your jobs, integrates well with LDAP, and has an amazing browsable REST API. Command line tools are available for easy integration
This section is new and evolving. The idea here is explore particular use cases in greater depth and provide a more "top down" explanation of some basic features.
IT automation solutions that work well for them. Should you wish to get more involved -- whether in terms of just asking a question, helping other users, introducing new people to Ansible, or helping with the software or documentation, we welcome your contributions to the project.
Learn how to build modules of your own in any language, and also how to extend Ansible through several kinds of plugins. Explore Ansible's Python API and write Python plugins to integrate with other solutions in your environment.
Developers will also likely be interested in the fully-discoverable `REST API <http://ansibleworks.com/ansibleworks-awx>`_ that is part of AnsibleWorks AWX. It's great for embedding Ansible in all manner of applications.
