I needed to do some testing of Juniper Contrail API calls, and for that I could use some Juniper switches controlled by Contrail. As Juniper has recently launched a virtual vEX image, I figured I’d give it a go. Below are build instructions for creating a vagrant box for Juniper vEX. Tools Vagrant: Vagrant from Hashicorp. Vagrant is a tool for building and managing virtual machine environments in a single workflow.