04/2015 Update : things have finally evolved since this post from 2013 : the next version of MDT (actually in beta state on connect) will fully support large image in UEFI media. You could also use version 2.1 and beyond of Rufus to create a UEFI media formatted in NTFS (sound crazy, but it just works, more details here)
Since UEFI was born, it has never been the popular standard that everybody love to talk about or even use… I’m not here to say that UEFI is bad, I use it on all my computers and have never found it any harder to use than BIOS.
Anyway, there’s one or two things that could have been done better, and if you ask me, the number one concern of this product is: FAT File format!!!
FAT is really dated and suffer from that horrible 4 GB max per file limit. If 4 GB was huge when the file system was created, it’s just a major problem nowadays especially when you are talking about deployment and our big WIM images file that embed a full operating system!
What we will cover:
UEFI file limitation is not a problem in all cases, it won’t cause you trouble if you deploy over SCCM 2012 R2, WDS, file Share or DVD. But if you had the genius idea to deploy Windows with MDT over an USB key… UEFI is your enemy!!!… Until you’ve read this post!
Requirements:
- Download Files LTIApply.wsf and MDT-Slasher.ps1. The first is a modified MDT script and the second is a Powershell UI script to import WIM images into MDT.
- ADK 8.1
- You’ll need (of course) an MDT 2012 U1 or MDT 2013 installation and an WIM image bigger than 4 GB.
- Powershell 4.0 which is the default if you are running Windows 8.1/Server 2012 R2 otherwise you’ll need to install this package.
- A FAT formatted USB key.
Installation:
Allow Powershell script execution by typing set-executionpolicy -ExecutionPolicy Unrestricted in an elevated PowerShell console.
Replace LTIApply.wsf from %deploymentshare%\scripts by the one you’ve just downloaded.
Launch MDT-Slasher-Final.ps1
Now, you are ready!
How to use :
If you are working from a network Deployment Share, you can easily use MDT-Slasher to split images that have already been imported, or you can import a new image that need to be split. The final step is to create an ISO media and to put its content on an USB key
If you work from an USB Deployment Share, you are already stuck by the 4 GB limit and can only use the import and split option.
In both scenarios, the first thing you’ll have to do will be to provide MDT-Slasher with a valid Deployment Share (DS). This DS will be the final destination where splited images will end-up.
If your DS already contains OS images, you will be able to pick one up to cut it down:
But if your image is not already part of the DS, just import it by specifying its path and an explicit folder name:
Once an image is specified, whether from the deployment share or from an external source file, you can hit the split button to begin the import.
When the import is finish, you can check in MDT that everything was successful:
You can also check in the folders that the image was really splited:
Okay! So now you’ve got something nice enough to work with, hope it will help. Suggestions/Bugs/Comments are welcome.
Behind the scene:
Some of you may say: “So you want us to believe that MDT can use split image simply because no you’ve found a way to import them? Are you fooling us?!!!”
No, there is no magic powder here! The “big” change is embedded in the LTIApply.wsf script. I’ve lightly modified it to support SWM files when they are detected in the Operating System folder.
Diagg