Migration with vMotion cannot proceed and issues a confusing error message when you connect multiple USB devices from an ESXi host to a virtual machine and one or more devices are not enabled for vMotion.

Problem

The Migrate Virtual Machine wizard runs a compatibility check before a migration operation begins. If unsupported USB devices are detected, the compatibility check fails and an error message similar to the following appears: Currently connected device 'USB 1' uses backing 'path:1/7/1', which is not accessible.

Cause

To successfully pass vMotion compatibility checks, you must enable all USB devices that are connected to the virtual machine from a host for vMotion. If one or more devices are not enabled for vMotion, migration will fail.

Solution

  1. Make sure that the devices are not in the process of transferring data before removing them.
  2. Re-add and enable vMotion for each affected USB device.