deandra.homeip.net

So, I've been playing with VBox on my laptop, and wanting to access files on a connected USB thumbdrive.

But try as I might, I cannot get the virtual machines to see attached USB devices. Turns out, it's due to a problem of permissions in Debian Lenny. Basically, /proc/bus/usb is mounted in such a way that VirtualBox cannot correctly enumerate the devices.

One solution involved adding an entry for /proc/bus/usb in /etc/fstab. But I found an easier solution, that doesn't involve changing system files and potentially opening up a security hole. (the Debian prople probably have the security set this way for a reason.)

This workaround works if you have the VBox Guest Additions installed in your VM, and if you're using the standard auto-mount functionality in GNOME that mounts USB devices under /media.

I added /media as a shared folder for the VM. Then in the (Windows) VM, I pointed Explorer at \\VBOXSVR\media\, and there's a folder for my thumbdrive.

Of course, this only allows you to access files on a USB drive. It doesn't allow you to access other USB devices, nor does it allow Windows to have low-level access to the device. If you want to do that, you need this fix:

Create a group called vboxusers or some-such. Add your user to that group.

Determine the numeric GID of the vboxusers group with the following command:

grep vboxusers /etc/group | awk -F: '{print $3}'

In my case, the GID of vboxusers is 120. If your number is different, substitute 120 for your own number in the following steps

Add the following line to /etc/fstab

none            /proc/bus/usb   usbfs   devgid=120,devmode=664  0       0

Unmount /proc/bus/usb and mount it.

If you had to create the vboxusers group, log out and back in again for the changes to take effect.

Now, VirtualBox will have full access to all your USB devices.

Source: http://www.howtoforge.com/installing-virtualbox-2-on-a-debian-lenny-desktop