vagrant up した時に共有フォルダのマウントでエラーが出る問題 ref: http://qiita.com/shifumin/items/a3f72225bcb947fcab21

file0.txt

$ vagrant up
(中略)
==> web: Mounting shared folders...
    web: /vagrant => /Users/hoge/path/to/dir/project
Failed to mount folders in Linux guest. This is usually because
the "vboxsf" file system is not available. Please verify that
the guest additions are properly installed in the guest and
can work properly. The command attempted was:

mount -t vboxsf -o uid=`id -u vagrant`,gid=`getent group vagrant | cut -d: -f3` vagrant /vagrant
mount -t vboxsf -o uid=`id -u vagrant`,gid=`id -g vagrant` vagrant /vagrant

The error output from the last command was:

/sbin/mount.vboxsf: mounting failed with the error: No such device

file1.txt

$ sudo /etc/init.d/vboxadd setup
Removing existing VirtualBox non-DKMS kernel modules       [  OK  ]
Building the VirtualBox Guest Additions kernel modules
The headers for the current running kernel were not found. If the following
module compilation fails then this could be the reason.
The missing package can be probably installed with
yum install kernel-devel-2.6.32-504.el6.x86_64

Building the main Guest Additions module                   [失敗]
(Look at /var/log/vboxadd-install.log to find out what went wrong)
Doing non-kernel setup of the Guest Additions              [  OK  ]

file2.txt

$ sudo yum install kernel-devel-2.6.32-504.el6.x86_64
読み込んだプラグイン:fastestmirror
インストール処理の設定をしています
Loading mirror speeds from cached hostfile
 * base: www.ftp.ne.jp
 * epel: ftp.kddilabs.jp
 * extras: www.ftp.ne.jp
 * remi-safe: remi.kazukioishi.net
 * updates: www.ftp.ne.jp
パッケージ kernel-devel.2.6 は利用できません。
エラー: 何もしません

file3.txt

$ sudo yum install ftp://mirror.switch.ch/pool/4/mirror/scientificlinux/6.6/x86_64/os/Packages/kernel-devel-2.6.32-504.el6.x86_64.rpm

file4.txt

$ sudo /etc/init.d/vboxadd setup
Removing existing VirtualBox non-DKMS kernel modules       [  OK  ]
Building the VirtualBox Guest Additions kernel modules
Building the main Guest Additions module                   [  OK  ]
Building the shared folder support module                  [  OK  ]
Building the OpenGL support module                         [  OK  ]
Doing non-kernel setup of the Guest Additions              [  OK  ]
Starting the VirtualBox Guest Additions                    [  OK  ]