Implementation of ubuntu host-to-host sharing in virtualbox

Prerequisites: VirtualBox is installed on the host Ubuntu and ubuntu is installed on the vbox. To use directory sharing, first Install Guest Additions in ubuntu, and select Devices-> Install Guest Additions. If the file cannot be downloaded, go to http://dlc.sun.com.edgesuite.net/virtualbox/self-check. I just downloaded VBoxGuestAdditions_4.1.2.iso. Then select the iso location under Settings-> Storage-> IDE Controller, and then select the directory to be Shared in Shared Folders. For example, my options are Folder Name: wujay and Folder Path: /home/wujay. remove the Auto mount check box (it cannot be checked here, otherwise the following sudo mount-t vboxsf wujay/mnt/host/will return an error:/sbin/mount. vboxsf: mounting failed with the error: Invilid argument). When you enter ubuntu, the VBoxGuestAdditions_4.1.2.iso disc is automatically loaded. Then, run autorun. sh. Restart ubuntu. Enter ubuntu again, ctrl + alt + t: sudo mkdir/mnt/hostsudo mount-t vboxsf wujay/mnt/host let Ubuntu automatically load the shared directory sudo vi/etc/fstab and add the following line wujay/mnt/host vboxsf rw, run the following command to uninstall gid = 100, uid = 1000, and auto 0: sudo umount-f/mnt/host. Note: the name of the shared folder must not be the same as that of the mount point. For example, the above mount point is/mnt/shared. If the shared folder name is also shared, the following error message will appear during mounting.
(See the official website of http://www.virtualbox.org/ticket/2265):/sbin/mount. vboxsf: mounting failed with the error: Protocol error author jayghost