I've been experimenting with OSD on UEFI-GPT based systems and came to this annoying discovery: The staging of WinPE is not supported [in NEWCOMPUTER deployment types].
My tests reveal that while ConfigMgr properly detects a UEFI environment, the OsdDiskPart.exe tool and the temporary DiskPartScript.txt file used to configure the drive does not create a proper UEFI-GPT layout; no minimum EFS (FAT32), MSR (Unallocated), or Windows (NTFS of remaining space) partitions, though the disk is properly converted to GPT.
In order to perform a successful UEFI-GPT based OSD, the boot image *MUST* match between the boot media and associated OSD task sequence. This could be a major problem for environments that rely on boot media to initiate deployments, as the media could easily be out of sync with the boot image (when updated after media has been created) associated with a task sequence due to the snapshot-in-time nature of physical media. The WinPE staging process was designed to use the boot image associated with the task sequence to insure an updated/approved boot image is used for deployment.
So, why hasn't Microsoft addressed this after several ConfigMgr iterations? Surely they must know that UEFI-GPT (no CSM support when UEFI revision C hits) will eventually (very near future???) supplant BIOS-MBR as the firmware and drive partition standards.
But then I got to thinking: How would Microsoft know how any entity would want to configure their drive's GPT layout?
I only need the required minimum EFS, MSR, and Windows partitions. Someone else in addition to the required minimum may need Bitlocker, a custom tools, or recovery partitions. There is no way for Microsoft to know everyone's GPT layout requirements; hence, no staging of WinPE in UEFI-GPT deployment environments.
You can successfully deploy to UEFI-GPT based systems, but it requires strict adherence to the matching of the boot image between boot media - USB, CD/DVD, PXE - and the associated task sequence.
Please share your thoughts or discoveries on this issue.
Am I on point , off base, or an obtuse piece of flotsam?
If my analysis is correct, it would have been nice of Microsoft to advise cutomers of this limitation.
V/R, Darrick West - Senior Systems Engineer, ConfigMgr: OSD