For the uninitiated, Varying Vagrant Vagrants is a project that builds a virtual machine running WordPress by using Vagrant. It configures a virtual machine with Nginx and serves up a few different versions of WordPress. Unrelatedly, Microsoft provides virtual machines for testing various versions of Internet Explorer. I needed to test something in IE8, so vagrant up, fire up the IE virtual machine, apologize to the memory of your laptop and away we go! It turns out the way Nginx is configured doesn’t make it easy to access the server from another machine on the same host. Varying Vagrant Vagrants will automatically update the hosts file on your local machine, but of course it cannot do this for another virtual machine you fire up. It turns out that, to access the server from one of the IE virtual machines, you need to add a few entries to the Windows hosts file on the IE virtual machine.
The Windows hosts file is located at C:\Windows\System32\drivers\etc\hosts and needs to be opened up as an Administrator. Assuming the Vagrant box has an IP address of 192.168.50.4, which is the default, the hosts file should have these lines added to it.