It took me a while to work out how to specify the bridged interface in Vagrant‘s Vagrantup file so that it doesn’t prompt you for it when you run vagrant up. I can be dumb at times, so it’s probably just me, but in case you don’t know Ruby syntax (like me), this is how you do it. In your Vagrantup file, assuming eth0 is the interface you want to bridge to, specify it like this:-

config.vm.network :bridged, :bridge => "eth0"

That’s it! If you’re not familiar with Vagrant, it’s a tool written in Ruby to provide a fast way to deploy virtual machines with VirtualBox. For more information, have a look at the overview over on the project’s website.