EFI Partition Order - Does it Matter?

rowlands111 · 17 Oct 2015

Hello everyone,

I decided to dedicate my Saturday evening off to somehow moving the EFI/Recovery/MSR partitions from my original SSD(Windows 8.1) to my new SSD (Windows 10) - when proceeding with dual booting Windows 10 I had left my old SSD attached, and I require the flexibility of being able to remove the new SSD and thus require the system partitions to be present on it.

Anyway, I ended up using Macrium to system image the system partitions from SSD 1 - then unallocated ~1GB space from SSD 2, and simply restored the three partitions via Macrium to the unallocated space.

It worked, I can boot etc. and the SSDs are not reliant on one another.

Is this partition order OK in terms of performance and best practice? (Nothing 'best practice' about using Macrium to transfer system partitions, I know)

EFI Partition Order - Does it Matter?-capture.png

Thank you

EDIT* I now dual boot via BIOS/UEFI - one listing is Windows Boot Manager, the other is UEFI:blahblah

fdegrove · 17 Oct 2015

Hi,

Although Windows may complain during it's installation when it sees itself forced to mess up the partition order, in practice I've never encountered any problem with it.

Note that Macrium Reflect allows you to fix that quite easily should you want to. Just make a backup of all partitions which are system related and restore the partitions in the correct order by dragging them one by one from the backup image to te destination disk in Macrium Reflect.

The only partition that may be critical is the MSR partition which is created when a MBR or RAW disk is converted from MBR to GPT. That one isn't visible is MS Disk Management but Macrium Reflect does show it IIRC.
I've never actually moved that one about so don't take my word for it.

In a multi-boot EFI system there would only be one EFI system partition which contains the BCD stores that allow you to launch the OS of your choice. This regardless whether a single HD is used or several ones.

But, since you're using the bootmenu from the EFI bios this doesn't really apply. As far as Windows is concerns you're running just a single system.

Cheers,

rowlands111 · 17 Oct 2015

Thanks very much for that :)

Definitely needed a second opinion from someone with experience.

Interesting you mention in a multi-boot EFI system there is only one EFI partition - honestly that's the conclusion I came too, and the only other alternative was to use the BIOS to select the bootable drive.
I understand what you mean regarding Windows and single system - as when an OS is booted from the BIOS; the drive that is booted is partitioned only with one OS.

Many thanks for your insight.

rowlands111 · 17 Oct 2015

fdegrove said:

Note that Macrium Reflect allows you to fix that quite easily should you want to. Just make a backup of all partitions which are system related and restore the partitions in the correct order by dragging them one by one from the backup image to te destination disk in Macrium Reflect.

I can already see my next night off being occupied with this now... darn, ignorance was so bliss!
Just kidding, I'll stick with what was said in that there are no issues with the particular order.