No puedo conectarme a Internet desde una máquina virtual Vagrant que he configurado.

Por ejemplo, en la raíz, cuando escribo:

curl http://google.com

Falla con el mensaje:

curl: (6) Couldn't resolve host 'google.com'

No estoy seguro de si se trata de una configuración de firewall, aunque, hasta donde yo sé, no he creado ninguna regla de firewall para el puerto 80 o cualquier otro puerto.

Aquí está la sección relevante de mi Vagrantfile. Si hay alguna otra información que pueda proporcionar, hágamelo saber en los comentarios:

Vagrant.configure("2") do |config|
  # All Vagrant configuration is done here. The most common configuration
  # options are documented and commented below. For a complete reference,
  # please see the online documentation at vagrantup.com.


  # Let Vagrant manage the hostname at boot
  config.vm.hostname = "devbox"

  # Create a forwarded port mapping which allows access to a specific port
  # within the machine from a port on the host machine. In the example below,
  # accessing "localhost:8080" will access port 80 on the guest machine.
  # config.vm.network :forwarded_port, guest: 80, host: 8080

  # Create a private network, which allows host-only access to the machine
  # using a specific IP.
  config.vm.network :private_network, ip: "10.0.0.10"

  # Create a public network, which generally matched to bridged network.
  # Bridged networks make the machine appear as another physical device on
  # your network.
  # config.vm.network :public_network

  # Create a public network with a given hardware address.  You can
  # configure your DHCP server (on your router) to assign a particular IP
  # address to the VM.  Update your hosts file accordingly.
  # config.vm.network :public_network, mac: "0a00251010101"

  # Share an additional folder to the guest VM. The first argument is
  # the path on the host to the actual folder. The second argument is
  # the path on the guest to mount the folder. And the optional third
  # argument is a set of non-required options.
  #config.vm.synced_folder "vagrant/logs", "/logs",
  #  owner: "root", group: "root"

  # Base box to use with Virtualbox provider
  config.vm.box = "debian-7.0.0-amd64-base"
  config.vm.box_url = "http:/mysite.com/debian-7.0.0-amd64-base.box"