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20.16.7. Redirected Devices

USB device redirection through a character device is supported by configuring it with management tools that modify the following section of the domain xml:

    <redirdev bus='usb' type='tcp'>
      <source mode='connect' host='localhost' service='4000'/>
      <boot order='1'/>
      <usbdev class='0x08' vendor='0x1234' product='0xbeef' version='2.00' allow='yes'/>
      <usbdev allow='no'/>

Figure 20.33. Devices - redirected devices

The components of this section of the domain XML are as follows:

Table 20.15. Redirected device elements

redirdevThis is the main container for describing redirected devices. bus must be usb for a USB device. An additional attribute type is required, matching one of the supported serial device types, to describe the host physical machine side of the tunnel; type='tcp' or type='spicevmc' (which uses the usbredir channel of a SPICE graphics device) are typical. The redirdev element has an optional sub-element address which can tie the device to a particular controller. Further sub-elements, such as source, may be required according to the given type, although atarget sub-element is not required (since the consumer of the character device is the hypervisor itself, rather than a device visible in the guest virtual machine).
bootSpecifies that the device is bootable. The order attribute determines the order in which devices will be tried during boot sequence. The per-device boot elements cannot be used together with general boot elements in BIOS boot loader section.
redirfilterThis is used for creating the filter rule to filter out certain devices from redirection. It uses sub-element usbdev to define each filter rule. The class attribute is the USB Class code.