Sun Microsystems VIRTUALBOX VERSION 3.1.0_BETA2 - Manual (Page 164)

11 Troubleshooting
there are communication problems (i.e. a VirtualBox application cannot communicate
with VBoxSVC), terminate the daemons and remove the local domain socket directory.
11.5.7 USB not working
If USB is not working on your Linux host, make sure that the current user is a mem-
ber of the vboxusers group. On older hosts, you need to make sure that the user
has permission to access the USB filesystem (usbfs), which VirtualBox relies on to
retrieve valid information about your host’s USB devices. The rest of this section only
applies to those older systems.
Note: The current rdesktop-vrdp implementation does not support accessing
USB devices through the sysfs!
As usbfs is a virtual filesystem, a chmod on /proc/bus/usb has no effect. The
permissions for usbfs can therefore only be changed by editing the /etc/fstab file.
For example, most Linux distributions have a user group called usb or similar, of
which the current user must be a member. To give all users of that group access to
usbfs, make sure the following line is present:
# 85 is the USB group
none /proc/bus/usb usbfs devgid=85,devmode=664 0 0
Replace 85 with the group ID that matches your system (search /etc/group for “usb”
or similar). Alternatively, if you don’t mind the security hole, give all users access to
USB by changing “664” to “666”.
The various distributions are very creative from which script the usbfs filesys-
tem is mounted. Sometimes the command is hidden in unexpected places.
For SuSE 10.0 the mount command is part of the udev configuration file
/etc/udev/rules.d/50-udev.rules
. As this distribution has no user group
called usb, you may e.g. use the vboxusers group which was created by the
VirtualBox installer. Since group numbers are allocated dynamically, the following
example uses 85 as a placeholder. Modify the line containing (a linebreak has been
inserted to improve readability)
DEVPATH="/module/usbcore", ACTION=="add",
RUN+="/bin/mount -t usbfs usbfs /proc/bus/usb"
and add the necessary options (make sure that everything is in a single line):
DEVPATH="/module/usbcore", ACTION=="add",
RUN+="/bin/mount -t usbfs usbfs /proc/bus/usb -o devgid=85,devmode=664"
Debian Etch has the mount command in /etc/init.d/mountkernfs.sh. Since
that distribution has no group usb, it is also the easiest solution to allow all members
of the group vboxusers to access the USB subsystem. Modify the line
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