Ansible is a great automation tool which should be in any developer or administrator's toolbox, just like Cobbler/Koan, Jenkins and others. Or as they put it:
No matter your role, or your automation goals, Ansible can help you connect teams and deliver efficiencies.
Ansible is an open source IT automation engine that automates provisioning, configuration management, application deployment, orchestration, and many other IT processes. It is free to use, and the project benefits from the experience and intelligence of its thousands of contributors.
It saves me so much time in the long run, and allows me, when combined with Cobbler/Koan, to quickly do things like build or rebuild a server from scratch, especially once I have a given set of scripts fine-tuned. I have used it to cleanly rebuild servers with larger virtual disks from the start, make a variant of another machine, or to even to things like adding a new PHP version to an existing machine. Simply edit a simple text file defining some variables in YAML format, save, and on my control server, running a playbook. Simple as that.
To read more, here are some resources for you: