Proxmox KVM usb passthrough

Open KVM monitor for your KVM machine in Proxmox GUI or in the command line with the following command:

# qm monitor 168
Entering Qemu Monitor for VM 168 - type 'help' for help
qm> 

Show the usb devices info from your host machine:

qm> info usbhost
  Bus 4, Addr 2, Port 1, Speed 12 Mb/s
    Class 00: USB device 046b:ff10, Virtual Keyboard and Mouse
  Bus 6, Addr 2, Port 2, Speed 1.5 Mb/s
    Class 00: USB device 0624:0294, Dell 03R874
  Bus 2, Addr 3, Port 1, Speed 480 Mb/s
    Class 00: USB device 0930:6533, DataTraveler 2.0
  Auto filters:
    Bus *, Addr *, Port *, ID 0930:6533

According to device “USB device 0930:6533” in the example, add the device to guest machine:

qm> device_add usb-host,id=myusb,vendorid=0x0930,productid=0x6533

Verify that the new usb device is added in your guest:

qm> info usb
  Device 0.1, Port 1, Speed 12 Mb/s, Product QEMU USB Tablet
  Device 0.3, Port 2, Speed 12 Mb/s, Product QEMU USB Hub
  Device 0.4, Port 2.1, Speed 480 Mb/s, Product DataTraveler 2.0

After using it, remove usb device from your guest:

qm> device_del myusb

If you run the command again, you will see the usb device is gone from your guest:

qm> info usb
  Device 0.1, Port 1, Speed 12 Mb/s, Product QEMU USB Tablet
  Device 0.3, Port 2, Speed 12 Mb/s, Product QEMU USB Hub

This has been tested in Proxmox 3.0/957f0862

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