6.5.1

If a host with connected USB devices resides in a DRS cluster with DPM enabled, you must disable DPM
for that host. Otherwise DPM might turn off the host with the device, which disconnects the device from
the virtual machine.
Configuring USB Devices for vMotion
With USB passthrough from a host to a virtual machine, you can migrate a virtual machine to another
ESXi host in the same datacenter and maintain the USB passthrough device connections to the original
host.
If a virtual machine has USB devices attached that pass through to an ESXi host, you can migrate that
virtual machine with the devices attached.
For a successful migration, review the following conditions:
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You must configure all USB passthrough devices connected to a virtual machine for vMotion. If one or
more devices is not configured for vMotion, the migration cannot proceed. For troubleshooting details,
see the vSphere Troubleshooting documentation.
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When you migrate a virtual machine with attached USB devices away from the host to which the
devices are connected, the devices remain connected to the virtual machine. However, if you
suspend or power off the virtual machine, the USB devices are disconnected and cannot reconnect
when the virtual machine is resumed. The device connections can be restored only if you move the
virtual machine back to the host to which the devices are attached.
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If you resume a suspended virtual machine that has a Linux guest operating system, the resume
process might mount the USB devices at a different location on the file system.
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If a host with attached USB devices resides in a DRS cluster with distributed power management
(DPM) enabled, disable DPM for that host. Otherwise DPM might turn off the host with the attached
device. This action disconnects the device from the virtual machine because the virtual machine
migrated to another host.
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Remote USB devices require that the hosts be able to communicate over the management network
following migration with vMotion, so the source and destination management network IP address
families must match. You cannot migrate a virtual machine from a host that is registered to vCenter
Server with an IPv4 address to a host that is registered with an IPv6 address.
Avoiding Data Loss with USB Devices
When a virtual machine connects to a physical UBS device on an ESXi host, virtual machine functions
can affect USB device behavior and connections.
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Before you hot add memory, CPU, or PCI devices, you must remove any USB devices. Hot adding
these resources disconnects USB devices, which might result in data loss.
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Before you suspend a virtual machine, make sure that a data transfer is not in progress. During the
suspend or resume process, USB devices behave as if they have been disconnected, then
reconnected. For information about suspend and resume behavior after migration with vMotion, see
Configuring USB Devices for vMotion.
vSphere Virtual Machine Administration
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