[CentOS-virt] Hot adding USB devices to guests at a fixed address

Tue Nov 26 16:45:43 UTC 2013
R P Herrold <herrold at owlriver.com>

On Tue, 26 Nov 2013, Stephen Harris wrote:

> I have a device I want a guest to see.  I've configured the following:

> And then in udev:
>   % cat /etc/udev/rules.d/90-owon.rules 
>   ACTION=="add", \
>     SUBSYSTEM=="usb", \
>     SYSFS{idVendor}=="5345", \
>     SYSFS{idProduct}=="1234", \
>     RUN+="/usr/bin/virsh attach-device XP_VM1 /etc/libvirt/HotPlug/owon.xml"

> Now this works; I plug the device in and the guest sees it.

most USB persistent enumeration are done by the device serial 
number, which should appear along with the Vendor and Product.

Can you expose that through the udev rules as well?
 
> Does anyone know of a way of adding a device so that it's at a known fixed
> address inside the guest?

seeking to 'nail it to' a fixed address is probably not the 
right way to do it, as that is detection order dependant

-- Russ herrold