For further information and detailed instructions on how this can be done, please visit the VSphere Support Page: Here

This website will have all information required to get a USB device setup with ESXi and VSphere. Once you authenticate to the DL3 the drive will show up as either one or two disks depending on if you have SafeConsole or the Virtual ISO setting turned on. At that point, you may continue with the VMware process like any other device. 

Connecting a DL3 to a virtual machine can be accomplished by using a guest PC and adding the device connection. 

You can add multiple USB devices to a virtual machine when the physical devices connect to a client computer running vSphere Web Client.

USB controller hardware and modules that support USB devices must exist in the virtual machine. 

The controller must be present before you can add USB devices to the virtual machine.

You can add up to 20 USB devices to a virtual machine. 

This is the maximum number of devices supported for simultaneous connection to one virtual machine.

A USB device is available to only one powered-on virtual machine at a time. 

When a virtual machine connects to a device, that device is no longer available to other virtual machines or to the client computer. 

When you disconnect the device from the virtual machine or shut down the virtual machine, the device will go back to the client computer and will be available to other virtual machines the host manages.

In order to avoid data loss, be sure that before you connect a device to a virtual machine, make sure the device is not in use on the client's computer.

There are some limitations with USB 3.0

There are 3 main limitations:

The virtual machine that you connect the USB 3.0 device to must be configured with an xHCI controller and have a Linux guest operating system with a 2.6.35 or later kernel.

You can connect only one USB 3.0 device operating at superspeed to a virtual machine at a time.

USB 3.0 devices are available only for passthrough from a client computer to a virtual machine. They are not available for passthrough from an ESXi host to a virtual machine.