title: vagrant port forwarding does not work
body: <p>I installed a precise32 VM using Vagrant in which I am trying to employ devstack for openstack developing. In order to access the service from host, I set up some forward ports in configure file but it does not work. That is I can not connect to 10.0.2.15 to which devstack prompted me to connect. I tried to switch the networking mode in VirtualBox from NAT to Bridge, then an error popped out saying something like "the NAT name already exists". I checked out the VirtualBox documentation but did not really understand. Anybody help me out please...</p>
  
  <p>I add following to vagrant configure file:</p>
  
  <pre><code>Vagrant::Config.run do |config|
  config.vm.forward_port 80, 9090
  config.vm.forward_port 5000, 5000
  config.vm.forward_port 5672, 5672
  config.vm.forward_port 3333, 3333
  config.vm.forward_port 8773, 8773
  config.vm.forward_port 8774, 8774
  config.vm.forward_port 8776, 8776
  config.vm.forward_port 8777, 8777
  config.vm.forward_port 9191, 9191
  config.vm.forward_port 9292, 9292
  config.vm.forward_port 35357, 35357
  config.vm.forward_port 40529, 40529
  config.vm.forward_port 47117, 47117
  config.vm.forward_port 55977, 55977
  config.vm.customize ["modifyvm", :id, "--memory", 8192]
  end
  </code></pre>