title: unknown filesystem type 'vboxsf' after vagrant up
body: <p>i want to setup environment using vagrant but display error after vagrant up. here is my spec</p>
  
  <p>im using :
  - OS X Yosemite Version 10.10.5
  - VirtualBox vesion 5.2.6
  - Vagrant 2.0.1</p>
  
  <p>and this is my Vagrant file</p>
  
  <pre><code>Vagrant.configure("2") do |config|
    config.vm.box = "centos/7"
    config.vm.network "private_network", ip: "192.168.33.99" 
    config.vm.synced_folder "./", "/vagrant", type:"virtualbox", :owner =&gt; 'apache', :group =&gt; 'apache', mount_option: ['dmode=777', 'fmode=755']
  end
  </code></pre>
  
  <p>but went i run 'vagrant up' it display error like this</p>
  
  <pre><code>Vagrant was unable to mount VirtualBox shared folders. This is usually
  because the filesystem "vboxsf" is not available. This filesystem is
  made available via the VirtualBox Guest Additions and kernel module.
  Please verify that these guest additions are properly installed in the
  guest. This is not a bug in Vagrant and is usually caused by a faulty
  Vagrant box. For context, the command attempted was:
  
  mount -t vboxsf -o uid=48,gid=48 vagrant /vagrant
  
  The error output from the command was:
  
  mount: unknown filesystem type 'vboxsf'
  </code></pre>
  
  <p>i did run this code</p>
  
  <pre><code>vagrant plugin install vagrant-vbguest
  vagrant vbguest
  </code></pre>
  
  <p>display error message</p>
  
  <pre><code>The distribution packages containing the headers are probably:
      kernel-devel kernel-devel-3.10.0-862.14.4.el7.x86_64
  An error occurred during installation of VirtualBox Guest Additions 5.2.6. Some functionality may not work as intended.
  In most cases it is OK that the "Window System drivers" installation failed.
  Redirecting to /bin/systemctl start vboxadd.service
  Job for vboxadd.service failed because the control process exited with error code. See "systemctl status vboxadd.service" and "journalctl -xe" for details.
  Unmounting Virtualbox Guest Additions ISO from: /mnt
  </code></pre>
  
  <p>and this code</p>
  
  <pre><code>vagrant plugin install vagrant-winnfsd
  </code></pre>
  
  <p>but still didn't work. anyone can help me?</p>
  
  <p>evendo i can go through with vagrant ssh. i can't update any file and folder in vagrant folder. </p>
  
  <p>what should i do</p>