The previous recipes launched instances into an existing environment, including existing networks, images and keys, for example. However, using Ansible for orchestration of OpenStack environments brings a full suite of modules that can be used to operate more than just Nova. For example, we can use Ansible to control Glance, Neutron, Cinder, and so on.
In this recipe, we only assume that a user is able to authenticate into a project. We don't assume that any networks exist, or even any images exist. We can get Ansible's view of the world to ensure that images and networks are present, and if not—create them.
Note that this recipe is intended to introduce you to the wonderful world of Ansible. The example is to show the creation of a stack from start to finish. Optimizing Ansible playbooks is beyond the scope of this book.