Ansible is a radically simple model-driven configuration management, deployment, and command execution framework. Other tools in this space have been too complicated for too long, require too much bootstrapping, and have too much learning curve. Ansible is dead simple and painless to extend. For comparison, Puppet and Chef have about 60k lines of code. Ansible’s core is a little over 1000 lines.

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Where Ansible excels though, is expressing complex multi-node deployment processes, executing ordered sequences on different sets of nodes through Playbooks. Playbooks contain one or more plays, each executed against a different batch of nodes. Think about webservers, database servers, and backend servers in a multi-node web environment. A play can address each set of machines in a cycle, ensuring the configurations of the machines were correct and also updating them to the specified version of software if required.