基于VirtualBox的Oracle Linux分辨率设置

在基于VirtualBox的Oracle Linux上布署11G RAC，执行grid Infrastructure 集群件安装的时候，OUI界面显示不全，右下角缺少"next"与"cancel"按钮，显示如下

相关阅读：

Virtualbox安装CentOS修改分辨率为1366x768  http://www.linuxidc.com/Linux/2012-12/75447.htm

在 Ubuntu 12.10 中使用 Virtualbox 安装 Win7 http://www.linuxidc.com/Linux/2012-11/74195.htm

Ubuntu中用VirtualBox虚拟机安装Windows XP完整图解 http://www.linuxidc.com/Linux/2010-09/28435p8.htm

VirtualBox 虚拟机安装 Ubuntu 13.10 截图 http://www.linuxidc.com/Linux/2013-11/92698.htm

点击"System"-->"Administrator"-->"Display"，将分辨率由640x480调整至800x600，然后logout重新登陆，问题依旧。

编辑/etc/X11/xorg.cnf文件，设置分辨率参数Modes，显示如下

Section "InputDevice"
Identifier "Keyboard[0]"
Driver "kbd"
Option "XkbModel" "pc105"
Option "XkbLayout" "us"
Option "Protocol" "Standard"
Option "CoreKeyboard"
EndSection

Section "InputDevice"
Driver "mouse"
Identifier "Mouse[1]"
Option "Buttons" "9"
Option "Device" "/dev/input/mice"
Option "Name" "VirtualBox Mouse Buttons"
Option "Protocol" "explorerps/2"
Option "Vendor" "Oracle Corporation"
Option "ZAxisMapping" "4 5"
Option "CorePointer"
EndSection

Section "InputDevice"
Driver "vboxmouse"
Identifier "Mouse[2]"
Option "Device" "/dev/vboxguest"
Option "Name" "VirtualBox Mouse"
Option "Vendor" "Oracle Corporation"
Option "SendCoreEvents"
EndSection

Section "ServerLayout"
Identifier "Layout[all]"
InputDevice "Keyboard[0]" "CoreKeyboard"
InputDevice "Mouse[1]" "CorePointer"
InputDevice "Mouse[2]" "SendCoreEvents"
Option "Clone" "off"
Option "Xinerama" "off"
Screen "Screen[0]"
EndSection

Section "Monitor"
Identifier "Monitor[0]"
ModelName "VirtualBox Virtual Output"
VendorName "Oracle Corporation"
EndSection

Section "Device"
BoardName "VirtualBox Graphics"
Driver "vboxvideo"
Identifier "Device[0]"
VendorName "Oracle Corporation"
EndSection

Section "Screen"
SubSection "Display"
Depth 24