Second HD not seen until after UEFI boot

I'm hoping that someone can help me cut through the thicket of my own ignorance concerning UEFI booting.

I installed Windows 7 Pro x64 to a GPT HD on a Lenovo TS140 server computer, so as to boot via UEFI. This is my first and only experience with UEFI. After an appropriate learning curve in installing, I now have a system that is reliable and very fast.

However, I have not been able to do something that I have been doing for years on BIOS/MBR systems--namely, boot from an alternate partition that contains a clone of my main Win7 boot partition. My strategy is to have a second boot partition on a second HD, which I refresh periodically using Casper 8 software. There are two entries in the boot menu: Win7 and Win7_alt.

On BIOS systems, this strategy works great. If I have a problem with the main boot partition, I can boot from the alternate, and if needed, I can restore the alternate back to the main.

But, on the UEFI machine, the second HD is not even visible during POST/BIOS setup as a bootable machine. It just isn't there, and consequently I can't boot from it. Once I'm booted, however, whether in Win7 or in a non-Windows CD/USB, drive 2 is alive and well and normal.

I'm reasonably sure that I'm the cause of the problem. I created the alternate partition originally by cloning HD 1 to HD 2. Casper seemed to do exactly what I asked. That is, it created a bootable partition and a healthy EFI System partition on HD 2. I suspect it's a problem that, as a clone, the second HD is identical to the first. Therefore, the UEFI software sees only one bootable partition.

Someone advised me that the drives definitely need to have different UUIDs, whatever those are. I have looked into software that purportedly lets me view and edit UEFI variables, but as a certified UEFI dunce, that would be like my performing brain surgery after consulting Google. While I would love to continue my backup-boot strategy with UEFI, I really don't want to hose my otherwise perfectly working system.

Any, and I do mean any, advice, thoughts, or hard truths will be greatly appreciated. In any case, thank you for taking the time to read this.

Bookmarked for future reference, thanks for sharing :)

Thanks for chiming in rvcjew, TVeblen, and GokAy.

The boot menu (yes, it is F12 on the TS140) does not show HD 2, just these:

SATA 4 (DVD ROM)
SATA 0 (HD 1) UEFI: Windows Boot Manager
Network 1


Here's the BIOS setup:

All SATA ports are enabled. CSM (Compatibility Support--booting via BIOS/MBR) is Enabled, and Boot Priority is UEFI First, but the symptoms are the same with CSM Disabled and with UEFI Only. I've also tried setting Hard Disk Pre-delay up to 30 seconds, in case HD 2 needed a little time to power up.

Boot Sequence is set as USB Key, DVDROM, and HD 1. HD 2 does not appear in the BIOS Boot Sequence menu.

Once I'm booted, HD 2 is alive and well. I just can't boot from it. It's not present on the BIOS (F12) boot menu. If I select Win7_alt (HD 2) from the Windows Boot Manager, it goes into Windows Recovery and then gives up and restarts, leading back to Windows Boot Manager.

I'm really out of my element here, but because HD 2 is a clone of HD 1, it makes sense to me that the UEFI boot software sees only one boot device. But, I don't know nearly enough about UEFI to start twiddling around with its innards. It seems that, somehow, I need to set UEFI up, such that it sees two distinct boot instances. But, that's just a guess.

Thanks again for weighing in.

TVeblen said:

So as an experiment you might try deleting the ESP on the second hard drive to see if that will clear up the problem. I don't believe an ESP is necessary on secondary drives for the file system. But, I have not tried this.

Good idea, TVeblen. That is certainly worth a try. Thanks for the suggestion. I will report back after I have tried this.