Force 3TB OS drive to MBR (max 2tb)

[trevmac77]

Hi all,

 

I have an unusual problem in that my employer is purchasing old Supermicro blade servers. They don't support SAS and as such I'm using large SATA drives and I'm pretty sure these are BIOS only as I didn't see anything in BIOS setup that looked like I could enable a UEFI boot mode (they are over 7 years old and cheap.) Currently, I've run down to 3TB and above and my 2016 installations are failing as SCCM is forcing initialization to GPT to use the 3TB capacity.  I need these to be MBR and 2TB for Windows to successfully be deployed.  The trouble is, I can't locate where the diskpart.exe and diskpartscript.txt are being run during the installation.  I'm guessing it's buried in a VBS script in the OSDDiskpart step but I haven't acquired the skills yet to get down to the granular level of tweaking.

So far I've tried enabling: Set Diskpart BIOS compatibility in both locations where it's greyed out.

Disabling all three Format and Partition Disk (UEFI) and tried flipping the Disk Type drop-down option in each UEFI format step to MBR from GPT, but for some reason that didn't work.

but the disk still gets initialized to GPT.

If I knew where the initialization step was taking place I could just add a WMI query that ignores Supermicro X8DTT-H or something similar.  Another possible solution would be to insert my own Diskpart script that converts it back to MBR right before it's failing.

Here's part of my log:

 

 

And here are the details of what's happening in Stdout:

Diskpart.exe STDOUT: 
Microsoft DiskPart version 10.0.14393.0

Copyright (C) 1999-2013 Microsoft Corporation.
On computer: MININT-7SO7UHO
       
  Volume ###  Ltr  Label        Fs     Type        Size     Status     Info
  ----------  ---  -----------  -----  ----------  -------  ---------  --------
  Volume 0     C                NTFS   Partition   2047 GB  Healthy            

Disk 0 is now the selected disk.
      
DiskPart succeeded in cleaning the disk.

Disk is uninitialized, initializing it to GPT.
 
DiskPart succeeded in creating the specified partition.

DiskPart successfully assigned the drive letter or mount point.

The selected disk is not a fixed MBR disk.
The ACTIVE command can only be used on fixed MBR disks.

 

Thanks for any help!  I'm just finding that the MDT task schedule is a bit blackboxed and I can't seem to find where this lives.
 

 

Edited June 3, 2018 by trevmac77

[anyweb]

it's more than likely forcing to GPT due to the bios mode being in UEFI, and that's a good thing, looking at the small snippet of log file you provided doesn't really help troubleshoot this however, we need the entire smsts.log to be sure what is being detected, and then, what steps are running, so can you attach it please