CentOS6.3是安装在VirtualBox虚拟机上，安装好以后最好再将VBoxAdditions增强功能装上，主要目的是能够在虚拟机和宿主机之间能够共享文件。
1. 更新内核。CentOS 6.3对应的kernel默认为2.6.32-279.el6.i686：
# uname -r
2.6.32-279.el6.i686
安装增强功能需要kernel-devel包，必须保证kernel-devel和kernel版本的一致。查看软件源中kernel-devel的版本：
]# yum info kernel-devel Loaded plugins: fastestmirror, refresh-packagekit, security Loading mirror speeds from cached hostfile * base: mirrors.163.com * extras: mirrors.163.com * updates: mirrors.163.com Available Packages Name : kernel-devel Arch : i686 Version : 2.6.32 Release : 279.19.1.el6 Size : 7.6 M Repo : updates Summary : Development package for building kernel modules to match the : kernel URL : http://www.kernel.org/ License : GPLv2 Description : This package provides kernel headers and makefiles sufficient to : build modules against the kernel package.
当前的kernel-devel版本是2.6.32-279.19.1.e16。因此，必须升级kernel：
# yum update kernel
升级完后必须重启系统，新的kernel才能被使用。
2. 安装kernel-devel和gcc。
# yum install kernel-devel gcc gcc-c++
3. 安装增强功能。进入增强功能光盘根目录，执行Linux下的安装命令：
# ./VBoxLinuxAdditions.run
Verifying archive integrity... All good.
Uncompressing VirtualBox 4.2.4 Guest Additions for Linux..........
VirtualBox Guest Additions installer
Removing installed version 4.2.4 of VirtualBox Guest Additions...
Removing existing VirtualBox non-DKMS kernel modules[确定]
Building the VirtualBox Guest Additions kernel modules
Building the main Guest Additions module[确定]
Building the shared folder support module[确定]
Building the OpenGL support module[确定]
Doing non-kernel setup of the Guest Additions[确定]
Starting the VirtualBox Guest Additions [确定]
Installing the Window System drivers
Installing X.Org Server 1.10 modules[确定]
Setting up the Window System to use the Guest Additions[确定]
You may need to restart the hal service and the Window System (or just restart
the guest system) to enable the Guest Additions.
Installing graphics libraries and desktop services components[确定]