Why does `vagrant up` cause the VirtualBox VM window to appear?

Question

After following the vagrant tutorial everything seems to be going fine. However something new and slightly annoying has started happening when I run vagrant up: VirtualBox also starts up and I see a VM window which seems to correspond to the Vagrant VM open. I've used Vagrant many times in the past without this happening, and IIRC even for this current vm that I'm using VirtualBox wouldn't necessarily open just because I ran vagrant up.

What is causing this? Why does vagrant up cause the VirtualBox VM window to appear? (and steal focus from my Mac OS X Terminal window, which is quite annoying)

Note: The answer in my case is not that Vagrant uses VirtualBox. If this were the case then VirtualBox would have always been opening in the background and I'm quite sure this is a new behaviour.

Answer 1

I see three possibilities:

• In your Vagrantfile, you configured gui = True (see GUI vs Headless)
• The box you use with Vagrant comes with gui = True setting in its Vagrantfile (Box contains initial Vagrantfile which is being merged when you do vagrant up)
• Possible bug in Vagrant and/or VirtualBox

It could be helpful if you specify your Vagrant & VirtualBox versions, and share with us your Vagrantfile.