Although a test cluster can be deployed on any hardware or virtual machine (VM), for the purposes of this book, a combination of Vagrant and VirtualBox will be used. This will allow rapid provisioning of the VMs and ensure a consistent environment.

VirtualBox is a free and open source type 2 (hosted) hypervisor currently being developed by Oracle. Performance and features may be lacking compared with high-end hypervisors, but its lightweight approach, and multi-OS support lends itself to be a prime candidate for testing.

Vagrant helps allow an environment that may comprise many machines to be created quickly and efficiently. It works with the concepts of boxes, which are predefined templates for use with hypervisors and its Vagrantfile, which defines the environment to be built. It supports multiple hypervisors and allows a Vagrantfile to be portable across them.