How to Add a Persistent Volume to Your Provisioned Virtual Machine in XenServer

XenDesktop How to Add an Additional Disk to VM : (XenDesktop)

To achieve this goal, perform the following steps:

Create a new VM in your XenCenter console.
Install a Windows server (2003 X86 in this example) on a VM with one logical disk. On this VM you have to install XenTools and Target device software (with Provisioning Services 5.6 when you install Target Device, XenConvert is installed too).
In this example, all the Windows updates are installed, disk part auto mount enabled (CTX122143 - How To Enable Automount to Automatically Assign a Drive Letter to a vDisk).
Create a vDisk on your Provisioning Services server.
Mount your vDisk.

In the Disk management menu, format the disk that you have just mounted.

Unmount your vDisk.

On your Provisioning Services server, create a new device. Put the MAC address of your VM (installed at step 1), Set boot from hard disk and attach your vDisk.

On your installed VM server, after a reboot, launch XenConvert (verify that your vDisk is in private mode). Your vDisk is filled.
In the XenCenter console, create a new VM without any disk. That VM will be converted into XenServer template later.
In Provisioning Services server, create a new device with the MAC address of your VM just created, set boot from vDisk and attach your vDisk.

Create the AD machine account.

In XenCenter console, on this VM, go to the Storage tab and add a local storage.

Boot your VM.
In the Disk management menu, assign a drive letter and format the new logical disk.
Stop your VM and convert it into a template.
Set your vDisk in standard mode.

You now have all the requirements to stream a target device with a logical disk which you can store data on that cannot be erased after a reboot. With the Xenserver template, create all the VMs. With Provisioning Services stream the vDisk. As result you have VMs with a logical disk which can store all the data that you wish to remain persistent .