Is UEFI/GPT difficult

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Bob Coleman
Posts: 785
Joined: Fri Aug 12, 2011 5:58 pm

Re: Is UEFI/GPT difficult

Post by Bob Coleman »

Brian K wrote:
> Bob,
>
> I just installed BIU to a 5 year old computer and saw issues similar to the
> ones you described. BIU wasn't in Boot Priorities until it was installed
> twice. The USB mouse didn't work in BIU. "Current" was
> temporarily in the Boot Priorities and it didn't boot BIU. I couldn't get
> rid of unwanted items in Boot Priorities. They would Disable but would
> reappear after the next boot.
>
> Now, apart from the mouse, BIU does work. It's an old computer and it will
> be going back into storage. It certainly looks like you need recent UEFI
> Firmware.

Interesting. There is a "PC BIOS Update" available from HP, but I have no reason to believe it has anything with this issue and am not sure I care to risk installing it.
TeraByte Support
Posts: 3598
Joined: Thu May 05, 2011 10:37 pm

Re: Is UEFI/GPT difficult

Post by TeraByte Support »

You can choose to boot any file you want, provided it's an UEFI executable.

UEFI spec requires a ESP.





brucebne
Posts: 159
Joined: Sat Jan 19, 2019 11:01 am

Re: Is UEFI/GPT difficult

Post by brucebne »

TeraByte Support wrote:
> You can choose to boot any file you want, provided it's an UEFI
> executable.
>
> UEFI spec requires a ESP.

UEFI spec requires an ESP folder for windows, mac, and boot managers, like BootIt.
But not for Linux OS.

A boot manager passes control to a boot loader.
Linux kernel files such as vmlinuz-4.19-x86_64, have a built in boot loader (boot stub).

So a boot manager like BIU, installed on ESP, can pass control directly to the kernel file's integrated boot loader....
This cuts out the need of each Linux OS to have grub install a folder on ESP, and avoids all the issues that can arise when deleting, restoring, moving Linux OS partitions.
Brian K
Posts: 2214
Joined: Fri Aug 12, 2011 1:11 am
Location: NSW, Australia

Re: Is UEFI/GPT difficult

Post by Brian K »

Bruce,

Can you delete the ESP and still boot a Linux OS? Or are you using BIU to boot the stub? Can you install a Linux OS to a GPT disk in a computer that doesn't have an ESP? I haven't tried these scenarios.
brucebne
Posts: 159
Joined: Sat Jan 19, 2019 11:01 am

Re: Is UEFI/GPT difficult

Post by brucebne »

Brian K wrote:
> Bruce,
>
> Can you delete the ESP and still boot a Linux OS? Or are you using BIU to
> boot the stub? Can you install a Linux OS to a GPT disk in a computer that
> doesn't have an ESP? I haven't tried these scenarios.



Brian,

1.
I haven't experimented deleting ESP. I need ESP to install and run a boot manager like BIU or rEFInd, and windows 10.....

2.
No I can't boot the stub with BIU because BIU only recognizes *.efi files as boot loaders.
It doesn't recognize the kernel files as able to boot the system.
So I boot Linux via *.efi files on the Linux partition.... either /boot/grub/x86_64-efi/core.efi or /grub.efi
This way I don't have to worry about ESP folders.

OTOH, rEFInd does recognize kernel files as boot loaders, and makes a boot item entry for i.e.
/boot/vmlinuz-4.20-x86_64
This totally negates the need for grub.

3.
You are asking the same question essentially as 1.
This should be possible because Linux OSs do not need ESP, which is how rEFInd works.
However, in practice, this no doubt depends on UEFI firmware capabilities....and as we both know, these vary significantly.
AGH1965
Posts: 85
Joined: Sat Jul 09, 2016 1:36 pm
Location: Netherlands

Re: Is UEFI/GPT difficult

Post by AGH1965 »

After a few weeks of struggling with BIU this longtime BIBM user concludes that BIU is more difficult to use than BIBM because of UEFI and GPT.

BIBM with EMBR was so easy to use. Especially configuring the Boot Menu was very straightforward. Partitions could easily be exchanged by simply putting another partition in a certain MBR slot. No Microsoft.00x folders or GUIDs that make exchanging partitions a painful job.

In my opinion BIU could be easier to use if OS partitions and Microsoft.00x folders would be unseparatable couples. If for example an OS partition named WIN123 would be accompanied by a Microsoft.WIN123 folder in which the BCD always "points" to OS partition WIN123, then configuring the Boot Menu could become more simple. Just select the desired OS partition and unvisible for the user BIU could select the corresponding Microsoft.WIN123 folder. Then it would also become possible to use the BCD editor of Partition Work by selecting the OS partition of which you want to edit the (corresponding) BCD.

Furthermore BIU could be easier to use if it would be possible to exchange the GUIDs of partitions in the Boot Menu. Windows uses the GUIDs for assigning drive letters. Since every partition in BIU has its own GUID, attempts to exchange partitions results in different drive letters assigned by Windows. Of course that can be fixed in Windows, but it would be nicer if this additional work could be prevented by BIU.

Maybe this all sounds very negative, but that is not intentional. Despite some peculiarities I find BIU a fantastic tool!
TeraByte Support
Posts: 3598
Joined: Thu May 05, 2011 10:37 pm

Re: Is UEFI/GPT difficult

Post by TeraByte Support »

If you copy a single partition over an existing one using disk imaging,
it will attempt to use the existing guid unless you force a change of guids.

On 12/31/2019 7:29 AM, AGH1965 wrote:
>
> Furthermore BIU could be easier to use if it would be possible to exchange the GUIDs of partitions in the Boot Menu. Windows uses the GUIDs for assigning drive letters. Since every partition in BIU has its own GUID, attempts to exchange partitions results in different drive letters assigned by Windows. Of course that can be fixed in Windows, but it would be nicer if this additional work could be prevented by BIU.
Eric
Posts: 224
Joined: Mon Sep 05, 2011 6:53 pm
Location: France

Re: Is UEFI/GPT difficult

Post by Eric »

You can pre-assigned letters in Windows with setwindl.tbs.

AGH1965 wrote:
> Furthermore BIU could be easier to use if it would be possible to exchange
> the GUIDs of partitions in the Boot Menu. Windows uses the GUIDs for
> assigning drive letters.
AGH1965
Posts: 85
Joined: Sat Jul 09, 2016 1:36 pm
Location: Netherlands

Re: Is UEFI/GPT difficult

Post by AGH1965 »

TeraByte Support wrote:
> If you copy a single partition over an existing one using disk imaging,
> it will attempt to use the existing guid unless you force a change of
> guids.

That's what I hoped, although I tried something slightly different. I restored an image of another partition over an existing partition. This resulted in the "hide" setting of two partitions being coupled for all Boot Menu items. If I hided one partition, both partitions became hidden; if I unhided one partition, both partitions became visible.
AGH1965
Posts: 85
Joined: Sat Jul 09, 2016 1:36 pm
Location: Netherlands

Re: Is UEFI/GPT difficult

Post by AGH1965 »

Eric wrote:
> You can pre-assigned letters in Windows with setwindl.tbs.

Thanks for the tip, but that is far beyond my skill level. Neither tbosdt_en_manual.pdf nor the readable part of setwindl.tbs gave me enough selfconfidence to give it a try.
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