XenServer USB Passthrough - A Detailed How-to Guide

USB passthrough to XenServer - the most versatile method

FlexiHub has an intuitive interface and offers an advanced USB over IP functionality that allows XenServer access to local USB devices.

When you find yourself in a situation when it is problematic to enable XenServer USB device passthrough, FlexiHub will help you to establish connections to real USB peripherals from your virtual machine with nothing more than a couple of mouse clicks.

One of the biggest advantages of FlexiHub is that it works on Windows, Linux, Android, and Mac operating systems. This means you can easily connect USB devices from Windows to Linux, from Linux to Mac, and in other combinations.

If you prefer the video guides, you can watch this step-by-step walkthrough:

Here you go! Now, the device that is attached to the host computer will appear in Citrix Hypervisor like it was connected directly to the guest.

What is Citrix Hypervisor?

Citrix Hypervisor (formerly XenServer) is a complex server virtualization platform with built-in enterprise-class features that allows you to easily manage mixed operating systems, storage, and data exchange configurations.

Citrix Hypervisor provides an efficient way of building a scalable system, as it can be used on the server hardware without any underlying OS.

This hypervisor is designed to virtualize hardware components like hard drives, ports, devices, etc. making them available to guest operating systems started on it.

Enable Citrix XenServer USB support in the hypervisor

Another way to make Citrix XenServer USB passthrough possible is to configure XenServer to work with locally attached USB devices.

Here’s how you can access local USBs in XenServer:

1. Attach a USB peripheral to the host where you run XenServer with the Enterprise Edition license, and you can see the USB tab with the USB devices list in the XenCenter.
2. To allow XenServer to pass through USB, select the USB device you need, click “Enable passthrough” and choose “Yes, enable passthrough” in the window that will appear.
3. Now, shut down the virtual machine that needs access to the USB device, as the hot plug option is not available.
4. Once done, connect the USB peripheral to the VM. To do this in XenCenter, right-click the virtual machine -> open Properties -> select USB -> click Attach -> choose the device you are going to attach -> hit Attach.
5. Launch your guest OS to access the attached USB device.

Also, note that it may be necessary to install the device driver on the guest machine for the device to work correctly.

USB devices can be detached from a virtual machine while it is running.

Use the following procedure to detach a USB device from Citrix XenServer:

1. From within XenCenter, right-click the VM.
2. Navigate to Properties > USB > select the USB peripheral that will be detached.
3. Click the Detach button and then Yes on the displayed pop-up window.
4. Click OK to complete the process.

USB passthrough requirements for XenServer

You need to take note of these restrictions and operating system requirements when considering implementing USB passthrough on XenServer.

You can only use USB passthrough with these HVM guests.

• Windows 7 SP1/8.1/10.
• Windows Server 2008 SP2/2008 R2 SP1/2012/2012 R2/2016.
• Linux: RHEL 7, Debian 8.

• XenServer 7.5 and above.
• XenServer Enterprise Edition or by using a XenDesktop/XenApp entitlement to access XenServer.
• When implementing USB passthrough to a virtual machine, the Pool Migrate, Storage Migrate, Snapshot, and Suspend operations are not supported.

Troubleshooting XenServer USB passthrough related issues

Here are a couple of common problems you might run into while using USB passthrough with XenServer.

1. Receiving this error when attaching a USB device: “The VM has too many VUSBs”.

This error indicates you have exceeded the maximum amount of USB devices that can be passed through to a specific VM. You can have up to six USB devices attached to the VM at the same time.

2. You don’t see the USB tab on XenCenter after you have connected a USB device on the XenServer host.

This error may be due to an improper license which disables the USB tab.

The USB tab doesn’t appear on XenCenter after connecting USB devices to the XenServer host. You need to use XenServer Enterprise Edition or access XenServer through a XenDesktop/XenApp entitlement when you want to implement USB passthrough functionality.