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Table Of Contents
With autoconnect enabled, the device connection re-establishes in the following cases:
n
The virtual machine is cycling through power operations, such as Power Off/Power On, Reset,
Pause/Resume.
n
The device is unplugged from the host then plugged back in to the same USB port.
n
The device is power cycled but has not changed its physical connection path.
n
The device is mutating identity during usage.
n
A new virtual USB device is added
The USB passthrough autoconnect feature identifies the device by using the USB path of the device on
the host. It uses the physical topology and port location, rather than the device identity. This feature can
seem confusing if you expect the autoconnect feature to match the connection target by device ID.
If the same device is plugged back in to the host through a different USB port, it cannot re-establish
connection with the virtual machine. If you unplug the device from the host and plug in a different device
to the same USB path, the new device appears and is connected to the virtual machine by the
autoconnect feature that the previous device connection enabled.
Autoconnect is useful in cases where devices mutate during usage. For example, for iPhones and other
such devices, the device VID:PID changes during software or firmware upgrades. The upgrade process
disconnects and reconnects the devices to the USB port.
The USB port is speed-specific. The autoconnect feature assumes that devices do not transition from
USB 1.1 (low-full speed) to USB 2.0 (high speed) or the reverse. You cannot interchange USB 2.0 high-
speed devices with USB 1.1 devices. For example, you might connect a USB 2.0 high-speed device to a
port and connect that device to the virtual machine. If you unplug the device from the host and plug a
USB 1.1 device into the same port, the device does not connect to the virtual machine.
For a list of supported USB devices for passthrough from an ESXi host to a virtual machine, see the
VMware knowledge base article at http://kb.vmware.com/kb/1021345.
vSphere Features Available with USB Passthrough
Migrations with vMotion and DRS are supported with USB device passthrough from an ESXi host to a
virtual machine.
Table 57. vSphere Features Available for USB Passthrough from an ESXi Host to a Virtual
Machine
Feature Supported with USB Device Passthrough
vSphere Distributed Power Management (DPM) No
vSphere Distributed Resource Scheduler (DRS) Yes
vSphere Fault Tolerance No
vSphere vMotion Yes
For details about migration with vMotion, see Configuring USB Devices for vMotion.
vSphere Virtual Machine Administration
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