vagrant upしてもVirtualBoxに表示されない

前提・実現したいこと

vagrant upをしたのですが、virtualboxを開くと現在稼働中の仮想マシンリストに何も表示されません。どのような原因が考えられますでしょうか。

vagrantbox.esより入手したbox

CentOS 6.6 x64 (Minimal, VirtualBox Guest Additions, Puppet 3.7.5 - see here for more infos)

vagrant statusの結果

default                   not created (virtualbox)

The environment has not yet been created. Run `vagrant up` to
create the environment. If a machine is not created, only the
default provider will be shown. So if a provider is not listed,
then the machine is not created for that environment.

vagrant upの結果

Bringing machine 'default' up with 'virtualbox' provider...
==> default: Importing base box 'centos6'...
==> default: Matching MAC address for NAT networking...
==> default: Setting the name of the VM: centos_default_1462506844291_40907
==> default: Clearing any previously set forwarded ports...
==> default: Clearing any previously set network interfaces...
==> default: Preparing network interfaces based on configuration...
    default: Adapter 1: nat
==> default: Forwarding ports...
    default: 22 (guest) => 2222 (host) (adapter 1)
==> default: Booting VM...
==> default: Waiting for machine to boot. This may take a few minutes...
    default: SSH address: 127.0.0.1:2222
    default: SSH username: vagrant
    default: SSH auth method: private key
    default: Warning: Remote connection disconnect. Retrying...
==> default: Forcing shutdown of VM...
==> default: Destroying VM and associated drives...
/opt/vagrant/embedded/gems/gems/vagrant-1.8.1/lib/vagrant/util/safe_chdir.rb:25:in `chdir': Too many open files - getcwd (Errno::EMFILE)
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/lib/vagrant/util/safe_chdir.rb:25:in `block in safe_chdir'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/lib/vagrant/util/safe_chdir.rb:24:in `synchronize'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/lib/vagrant/util/safe_chdir.rb:24:in `safe_chdir'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/lib/vagrant/util/subprocess.rb:121:in `execute'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/lib/vagrant/util/subprocess.rb:22:in `execute'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/plugins/providers/virtualbox/driver/base.rb:430:in `block in raw'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/lib/vagrant/util/busy.rb:19:in `busy'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/plugins/providers/virtualbox/driver/base.rb:429:in `raw'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/plugins/providers/virtualbox/driver/base.rb:367:in `block in execute'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/lib/vagrant/util/retryable.rb:17:in `retryable'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/plugins/providers/virtualbox/driver/base.rb:362:in `execute'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/plugins/providers/virtualbox/driver/version_5_0.rb:548:in `read_state'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/plugins/providers/virtualbox/provider.rb:97:in `state'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/plugins/providers/virtualbox/provider.rb:69:in `ssh_info'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/lib/vagrant/machine.rb:425:in `ssh_info'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/plugins/communicators/ssh/communicator.rb:319:in `connect'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/plugins/communicators/ssh/communicator.rb:64:in `block in wait_for_ready'
    from /opt/vagrant/embedded/lib/ruby/2.2.0/timeout.rb:88:in `block in timeout'
    from /opt/vagrant/embedded/lib/ruby/2.2.0/timeout.rb:32:in `block in catch'
    from /opt/vagrant/embedded/lib/ruby/2.2.0/timeout.rb:32:in `catch'
    from /opt/vagrant/embedded/lib/ruby/2.2.0/timeout.rb:32:in `catch'
    from /opt/vagrant/embedded/lib/ruby/2.2.0/timeout.rb:103:in `timeout'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/plugins/communicators/ssh/communicator.rb:42:in `wait_for_ready'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.8.1/lib/vagrant/action/builtin/wait_for_communicator.rb:16:in `block in call'

vagrantfileの中身

# -*- mode: ruby -*-
# vi: set ft=ruby :

# All Vagrant configuration is done below. The "2" in Vagrant.configure
# configures the configuration version (we support older styles for
# backwards compatibility). Please don't change it unless you know what
# you're doing.
Vagrant.configure(2) do |config|
  # The most common configuration options are documented and commented below.
  # For a complete reference, please see the online documentation at
  # https://docs.vagrantup.com.

  # Every Vagrant development environment requires a box. You can search for
  # boxes at https://atlas.hashicorp.com/search.
  config.vm.box = "centos6"

  # Disable automatic box update checking. If you disable this, then
  # boxes will only be checked for updates when the user runs
  # `vagrant box outdated`. This is not recommended.
  # config.vm.box_check_update = false

  # 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: "192.168.33.10"

  # 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"

  # 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 "../data", "/vagrant_data"

  # Provider-specific configuration so you can fine-tune various
  # backing providers for Vagrant. These expose provider-specific options.
  # Example for VirtualBox:
  #
  # config.vm.provider "virtualbox" do |vb|
  #   # Display the VirtualBox GUI when booting the machine
  #   vb.gui = true
  #
  #   # Customize the amount of memory on the VM:
  #   vb.memory = "1024"
  # end
  #
  # View the documentation for the provider you are using for more
  # information on available options.

  # Define a Vagrant Push strategy for pushing to Atlas. Other push strategies
  # such as FTP and Heroku are also available. See the documentation at
  # https://docs.vagrantup.com/v2/push/atlas.html for more information.
  # config.push.define "atlas" do |push|
  #   push.app = "YOUR_ATLAS_USERNAME/YOUR_APPLICATION_NAME"
  # end

  # Enable provisioning with a shell script. Additional provisioners such as
  # Puppet, Chef, Ansible, Salt, and Docker are also available. Please see the
  # documentation for more information about their specific syntax and use.
  # config.vm.provision "shell", inline: <<-SHELL
  #   sudo apt-get update
  #   sudo apt-get install -y apache2
  # SHELL
end