This post was originally written in 2014, using a technique that only easily allows testing on Ubuntu 12.04; since then, I've been adapting many of my roles (e.g. geerlingguy.apache) to use a Docker container-based testing approach, and I've written a new blog post that details the new technique: How I test Ansible configuration on 7 different OSes with Docker. Since I'm now maintaining 37 roles o