How to connect a USB device to a VM?

For the virtual machine (VM) to work with external USB devices, configure port redirection on the cluster node:

Connect the USB device to the cluster node where the VM is located.
Connect to the cluster node via SSH.

Define the full name of the VM (Name column):

virsh list --all

Example output

  Id    Name         State
---------------------------
 145   115_name1    running
 159   2218_name2   running
 223   1736_name3   running
 523   2117_name4   running

Determine the type of controllers added to the VM: get the xml description of the VM and filter by USB controllers:
```
virsh dumpxml <vm_name> | grep -i -E 'uhci|ehci|xhci'
```
Example output
```
<controller type='usb' index='0' model='piix3-uhci'>
<controller type='usb' index='0' model='ehci'>
<controller type='usb' index='1' model='nec-xhci'>
```
Comments

piix3-uhci — USB1
ehci — USB2
nec-xhci — USB3
index='N' — controller number
Get the bus_id and device_id of your USB device by getting a list of connected USB devices:
```
lsusb -v
```
Example output
```
Bus <bus_ID> Device <device_ID>: ID 0cd2:1402 Netac Technology Co., Ltd OnlyDisk
```
Create a file /root/usb_device.xml with the following contents:
```
<hostdev mode='subsystem' type='usb'>
<source>
<address bus='<bus_ID>' device='<device_ID>'/>
</source>
<address type='usb' bus='1' port='0'/>
</hostdev>
```
Comments
Values obtained in step 5:
- <bus_ID> — Bus ID
- <device_ID> — device ID
bus='1' — controller number from the command output in step 4. In this example, the output is the nec-xhci controller (USB3) because its value index='1'.
port='0' — VM port number

Enable port forwarding:

virsh attach-device <vm_name> --file /root/usb_device.xml --config --persistent

Comments