What is Ansible?
Ansible is a configuration management and deployment system, like Puppet, Capistrano, Fabric, and Chef. Its aim is to be radically simple and let you use your existing scripts to help with cluster configuration and software deployment whenever possible. Here are the ways that Ansible differentiates itself.
Ansible does not include a client/server architecture with pull-based clients (although in more recent versions, it does include pull-based configuration and deployment). Rather, it uses pre-existing network infrastructure: SSH. Every company has SSH installed on their cluster servers, and Ansible simply rides on top of this infrastructure to get the code and configuration out to the nodes.