Is UEFI/GPT difficult

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

Re: Is UEFI/GPT difficult

Post by brucebne »

Brian K wrote:
> Bruce,
>
> I assume you are using BIU. For each Linux install select the ESP in the
> "Device for boot loader installation" field.
>
> Each Linux install will create its own folder in the ESP. For example, if
> you installed Mint Cinnamon, Ubuntu and Fedora you would have these folders
> in the ESP. ubuntu.001, ubuntu.002 and fedora.001. Each folder contains
> grub, etc.
>
> Or did you mean something else?

Hi Brian,

OK, I just did a fresh install of Manjaro to ensure I got my explanation straight.

For install, I did the following:

- ensured ESP was recognized, and that boot and EFI flags were ticked.
- ensured the OS partition did not have a boot flag ticked.

The result on reboot is

- BIU was bypassed, and a Manjaro grub installation presented a boot menu.
- on getting into the OS, ESP has had the following folder added /EFI/Manjaro.
- no other folders have been added to ESP
- within /EFI/Manjaro/ is one file = grubx64.efi

So where are the grub program's files installed?
They are installed on the Manjaro OS partition at
/boot/efi/grub/

There are three folders
/fonts/
/themes/
/x86_64-efi/

and 2 files in the main folder
grub.cfg
grubenv

So in this setup, Manjaro has been registered with UEFI as the default system to boot.

So on bootup, UEFI passes control to
ESP at /EFI/Manjaro/grubx64.efi

This file passes control to grub which displays the boot menu.
And selecting the Manjaro option passes control to the Manjaro kernel with its integrated boot stub.

The kernel file in this case is
/boot/vmlinuz-4.19-x86_64

--------------------------------------------------------

OK, that's a pretty clear explanation of a reasonably clear Linux installation.
Grub can be reinstalled and updated, and the only thing that will change on ESP is /EFI/Manjaro/grubx64.efi

However, some Linux distros install the grub program in its entirety on ESP under a folder called /EFI/grub/....other distros install selected grub program files on ESP under /EFI/ubuntuxxx/


My question relates to this variation between Linux OSs in what folders/files they place in ESP.

This is especially pertinent when one starts running clones of the same Linux OS.
Because a clone OS will need its own install of the grub program in addition to its own folder i.e. ESP /EFI/ubuntu.00x+1

THis is important so as to keep independent installs of grub program for each incidence of an OS especially when there's an original OS and a clone of it.

---------------------------------------------------

These variations in what each OS installation does on ESP are why I think a boot menu program such as BIU would be simpler if it probed for Linux OS kernel files and made boot menu items for these. This bypasses the confusion generated when using grub as an intermediary, especially so when booting from original and clone OSs.
Brian K
Posts: 2221
Joined: Fri Aug 12, 2011 1:11 am
Location: NSW, Australia

Re: Is UEFI/GPT difficult

Post by Brian K »

brucebne wrote:

> However, some Linux distros install the grub program in its entirety on ESP under a
> folder called /EFI/grub/....other distros install selected grub program files on ESP
> under /EFI/ubuntuxxx/
>
>

Bruce, which ones create /EFI/grub/...? I must have been fortunate to miss those ones.

I've been concentrating on distros that support Secure Boot and Manjaro misses out. I did disable Secure Boot and install Manjaro and as you noticed, there was only a single file in Manjaro.001. I've since removed Manjaro.

I have the 3 Mints, Ubuntu, Kubuntu, OpenSUSE, Fedora and CentOS all working with Secure Boot.
brucebne
Posts: 159
Joined: Sat Jan 19, 2019 11:01 am

Re: Is UEFI/GPT difficult

Post by brucebne »

Brian K wrote:
> Bruce, which ones create /EFI/grub/...? I must have been fortunate to miss those
> ones.
>
> I've been concentrating on distros that support Secure Boot and Manjaro misses out. I
> did disable Secure Boot and install Manjaro and as you noticed, there was only a
> single file in Manjaro.001. I've since removed Manjaro.
>
> I have the 3 Mints, Ubuntu, Kubuntu, OpenSUSE, Fedora and CentOS all working with
> Secure Boot.

Ahh...so another point of difference is secure boot compatibility.
that complicates things further.

It's been a few weeks since I experimented Brian, and deleted due to time consumed.
I tried Mint, Elementary, Debian, Suse, MX, Manjaro, Lubuntu, Ubuntu, Peppermint, and I think 2 more.
They each had a slightly different way of installing grub.
This is what makes UEFI/GPT difficult, at least for Linux, and at least for cloning.

I am left with Mint and Manjaro ....once I sorted the boot pecularities, they are both excellent for my mostly business needs. though there's a couple of pieces of proprietary software I need to retain Win10 for.
i.e.
intelerad inteleviewer
Brian K
Posts: 2221
Joined: Fri Aug 12, 2011 1:11 am
Location: NSW, Australia

Re: Is UEFI/GPT difficult

Post by Brian K »

Bruce,

I just noticed a few differences with our Manjaro installs. You had...

> /EFI/Manjaro/

I had /EFI/Manjaro.001/

You mentioned "So where are the grub program's files installed?
They are installed on the Manjaro OS partition at
/boot/efi/grub/"

I don't have Manjaro installed anymore but I do have a backup image. TBIView shows the /boot/efi folder to be empty. There is no /boot/efi/grub/
Is /boot/efi/grub/ present in your backup image?

We noticed a similar finding with Mint, earlier in this thread, and concluded /boot/efi/grub/ was similar to a Junction point in Windows. It's all very confusing.

TBIView does show /boot/grub which contains...

/fonts/
/themes/
/x86_64-efi/

and 2 files
grub.cfg
grubenv
brucebne
Posts: 159
Joined: Sat Jan 19, 2019 11:01 am

Re: Is UEFI/GPT difficult

Post by brucebne »

Brian K wrote:
> Bruce,
>
> I just noticed a few differences with our Manjaro installs. You had...
>


Brian,

The insto I did yesterday I chose to boot via ESP and grub, as opposed to making a BIU boot menu item using an *.efi in the Manjaro fs.

So confirming the Manjaro fs:
- yes there is a junction point to ESP
i.e.
Manjaro root /boot/efi/ are folders/files on the Manjaro fs.

/boot/efi/EFI/* is the junction point to ESP's fs

I can confirm this by unmounting ESP, which makes /EFI/* disappear from Manjaro's fs.

________________________________________


As for Manjaro root /boot/efi/grub/
So I just rechecked, and I am terribly sorry but I got that address wrong.

grub is installed on Manjaro fs at /boot/grub/ NOT /boot/efi/grub/
DrTeeth
Posts: 1289
Joined: Fri Aug 12, 2011 6:58 pm

Re: Is UEFI/GPT difficult

Post by DrTeeth »

On Mon, 11 Feb 2019 19:07:00 PST, just as I was about to take a herb,
Bob Coleman disturbed my reverie and wrote:

> but also so I will have some experience with these things if I ever buy another UEFI/GPT PC.

Hi Bob,

I get computers built to my spec. That means no hard drives and I just
transfer my hard drives from one computer to another. I only use MBR.
--
Cheers,

DrT

** Amateurs built the Ark, but professionals built the Titanic.**
Brian K
Posts: 2221
Joined: Fri Aug 12, 2011 1:11 am
Location: NSW, Australia

Re: Is UEFI/GPT difficult

Post by Brian K »

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

Re: Is UEFI/GPT difficult

Post by brucebne »

An additional difficulty with UEFI/GPT is this:

BIU does not permit booting Linux OSs via the OS kernel file (with its built in boot stub).

Therefore BIU requires each Linux install be mediated by grub, so that a folder is created on ESP.
If an OS has no folder on ESP, then the OS cannot be booted reliably via a BIU boot menu item.

So, if you are experimenting with distros, every time you create or delete or restore an OS, you have to ensure that OS's ESP folder is created, deleted, or restored.

This is a ridiculous scenario.
It means essentially that no longer is an OS partition an independent and self contained unit.
Rather, it's most critical folder is not on the OS partition.
Brian K
Posts: 2221
Joined: Fri Aug 12, 2011 1:11 am
Location: NSW, Australia

Re: Is UEFI/GPT difficult

Post by Brian K »

brucebne wrote:

> Rather, it's most critical folder is not on the OS partition.

Microsoft started doing this with Win7. (Having the booting files in a non OS partition) It's not going to change with Windows10 and beyond.

I think the Linux booting files need to be in the ESP for Secure Boot to work.
brucebne
Posts: 159
Joined: Sat Jan 19, 2019 11:01 am

Re: Is UEFI/GPT difficult

Post by brucebne »

Brian K wrote:
> brucebne wrote:
>
> > Rather, it's most critical folder is not on the OS partition.
>
> Microsoft started doing this with Win7. (Having the booting files in a non OS
> partition) It's not going to change with Windows10 and beyond.
>
> I think the Linux booting files need to be in the ESP for Secure Boot to work.

Yes, I think you are right that Linux will not boot under Secure Boot, unless Linux has an ESP folder.

However,
- Windows needs an ESP folder.
- Linux doesn't. Linux doesn't even need an ESP partition.

ESP is an unnecessary convoluted complication created by Microsoft....and makes experimenting with, setting up and maintaining multiboot systems fraught with time consuming and unpredictable problems.

ESP creates an environment that is totally different to MBR, and its mgt by BING and BIBM.

For those wanting to enter the realm of Linux, BIU would benefit from having an OS probe that identifies and permits booting from Linux kernel files
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