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
在 Ubuntu 12.10 中使用 Virtualbox 安装 Win7
Ubuntu中用VirtualBox虚拟机安装Windows XP完整图解
VirtualBox 虚拟机安装 Ubuntu 13.10 截图
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
Modes "1024x768" "800x600" "640x480"
EndSubSection
Device "Device[0]"
Identifier "Screen[0]"
Monitor "Monitor[0]"
EndSection
然后重启系统，问题依旧，并且点击"System"-->"Administrator"-->"Display"，发现可选分辨率还是只有640x480和800x600。