Recipe - App Layering and Citrix Provisioning BDM

[Rob Zylowski]

Citrix Provisioning works by having “Provisioning Targets” or Windows Virtual Machines boot from centralized “Provisioning Servers” across the network. There are several ways to initiate the network boot but they all require defining a TFTP boot server where the target can download a bootstrap file. This process can be initiated using PXE or DHCP scope options.  It can also be initiated using a file attached to the target directly.  The file can be an ISO mapped to a DVD drive or a BDM partition or disk. I personally prefer the BDM disk option because the ISO is normally single point of failure while there would be a BDM for each target stored with the virtual machine on the hypervisor’s storage.

 

BDM disks or partitions can be created using the Citrix Boot Device Manager Utility that is installed with the Citrix Provisioning console. However, its much easier to create them automatically when deploying targets using the XenDesktop Setup Wizard. I think where customers have confusion with App Layering is that they try to add a BDM partition to the OS Layer rather then just adding a BDM disk directly to a target.

 

In the end what I found was that I was able to use the XenDesktop Setup wizard to create targets with BDM disks that just work.  I was also then able to copy one of the BDM disks to the folder for a different target and add that BDM disk as SCSI 0:0 and it would also work.  I could also use the same disk to deploy targets using the Streamed VM Setup Wizard and that worked as well.  The key was to assign the disk to the first SCSI slot (0:0). I would recommend that even if you want to retrofit BDM disks to existing targets you create the BDM disk using the XenDesktop Setup Wizard, then you copy that to the desired targets.