Oracle VirtualBox 虚拟机，为了在主机、从机间拷贝文件，共享剪贴板，需要进行设置，以及安装guest additions软件
测试环境
host: windows 7 professional 64位
virtual box guest: Lubuntu
设置
machine -> settings -> General -> Advanced
Shared Clipboard: bidirectional
Drag and drop: bidirectional
安装guest additions
1) add cdrom in storage setting
2) load "VBoxGuestAdditions.iso"， 或 device -> insert guest additions image
3) sudo mount /dev/cdrom /mnt
4) cd /mnt
5) sudo ./VBoxLinuxAdditions.run
6) reboot