Getting LSI MegaRaid controller to use UEFI partition beyond 2 TB

Dana Friedman
Dana Friedman used Ask the Experts™
on
I have a Dell Precision workstation that needed a new RAID controller. The closest match available to the one in the system would not recognize the foreign drives and array from the old controller. I created a new 9TB array, downloaded the OS (Windows 7 Ultimate) to a flash drive. That's how Dell shipped the system. I can boot the OS with an MBR-formatted USB stick that sees UEFI. I have the driver for the RAID controller, and the computer sees the controller and the drives after the driver's loaded. However, it won't see a partition larger than 2TB, and won't format/install WIndows on any partition/space on this array.
Questions: Using Rufus or some other such tool, how do I put the OS on a stick that'll allow it to see and USE one large partition (or maybe two smaller ones, but use the entire 9 TB)? THANKS! :)
Comment
Watch Question

Do more with

Expert Office
EXPERT OFFICE® is a registered trademark of EXPERTS EXCHANGE®
Philip ElderTechnical Architect - HA/Compute/Storage

Commented:
Boot into the RAID Controller BIOS and set up two logical disks:
 * LD 0: 500GB for Windows OS (Set as Boot)
 * LD 1: 8.5TB for Data/Guest VM files

When installing software install into the second partition. Set up any virtual machines, if any, on the second partition.

This is the best way to do it.
Scott SilvaNetwork Administrator

Commented:
Partitions need to be GPT to be readable over 2TB. MBR won't work that big...

Author

Commented:
Scott:

YES, I know that GPT is required for over 2 TB, but it didn't let me do that. I got an error message from Dell saying they're MBR partitions in an EFI environment (I'm paraphrasing the error message). It sounded wrong, but...<<sigh>>

Thanks!
Fundamentals of JavaScript

Learn the fundamentals of the popular programming language JavaScript so that you can explore the realm of web development.

Author

Commented:
Philip: your recommendation makes sense, and it's the last thing I'll try before connecting one drive to the motherboard for boot, and putting the others in a NAS box. :)

I will try it.

BUT, how did Dell ever do it when the system shipped?

Thanks,
Dana
Philip ElderTechnical Architect - HA/Compute/Storage

Commented:
Another option that I can think of off the top.

Set up the single array.

Boot to Installer and choose Repair/Recover then head into CMD.

You may need to load the RAID driver prior.

Once in, use DiskPart to set up a single GPT volume leaving 1GB at the end that Windows will use for the boot partition(s).

Once the partition is complete, you may need to head into the server's BIOS to verify the RAID array/logical disk is in Position 0.

Using the Windows installer you should be able to install from there.

Make sure the BIOS is set to uEFI Mode!

Author

Commented:
Eep. The first one sounds easier. :)
Thanks! I'll try the first option.
Philip ElderTechnical Architect - HA/Compute/Storage

Commented:
It reminds me of the hoops we had to jump through to get Windows NT and/or Windows 95 to install into a partition that was larger than I think it was 2GB!
Top Expert 2014

Commented:
Slicing 2TB+ arrays up in hardware and then sticking them together again using dynamic disks was just nasty :(

Knowing the serial no or the model of the original and new controllers we could probably see why it wouldn't import. Dell probably used a PERC and although they are from LSI and run their RAID stack the metadata may well be incompatible with each other.

Author

Commented:
Andy: I got past the non-import. I just recreated the array. Even though it feels a little like defeat, I'm going to try Philip's suggestion before giving up and sticking the drives in a NAS box. :)
Top Expert 2014

Commented:
You did ask "BUT, how did Dell ever do it when the system shipped? [and why can't I] " and we could possibly find out from the SN/asset tag as dell's support site sometimes has the RAID and OS configuration as well as the bill of materials for the individual machine build. Just as a matter of interest, Philip's method is the answer.

Author

Commented:
I could NOT call this "my own solution", because Philip helped get me there. I created a second virtual drive (500 GB). It offered to allow me to install Windows on either the 500 GB partition, OR the remaining 7.5 TB of unallocated space, once I turned it into a partition.

Put WIndows on the C partition, and the D partition was 7.5 TB, and I could write to it. I now see that the user's image (only backup) has everything (data, OS, applications) on the C partition. Reimaging the drive  would require the whole 8.7 TB on one partition. SO, I tried everything again, reconfiguring it as only ONE Virtual Drive. (RAID BIOS was only available in Legacy mode). After going back to UEFI mode, I booted from the USB stick, loaded the RAID controller driver, saw 1 big partition, pointed WIndows at it, and we're off and running. I have no explanation for why it worked. I'm sure SOMETHING changed, but I don't know what. Regardless, your help was invaluable in getting me there. (Invaluable is, of course, the opposite of what some might think it means. I could not place a value on it.). THANKS. HAPPY NEW YEAR!
Commented:
See comment above. It wasn't really all me, but this is how we close cases out here. THANK YOU, ALL! :)

Author

Commented:
Thank you all! Happy New Year! :)
Philip ElderTechnical Architect - HA/Compute/Storage

Commented:
A Happy New Year to all y'all! :)

Author

Commented:
Postscript: the array kept crashing, and the Windows install kept getting  trashed during driver installations. I told the user that continuing to troubleshoot five year old hardware is not advisable.  We're getting her a fast machine, a NAS, and a good local and cloud backup.

Do more with

Expert Office
Submit tech questions to Ask the Experts™ at any time to receive solutions, advice, and new ideas from leading industry professionals.

Start 7-Day Free Trial