Can I boot from more than one GPT partition?

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Re: Can I boot from more than one GPT partition?

Postby Bob Coleman » Fri Mar 10, 2017 11:40 am

DrTeeth wrote:
> On Thu, 9 Mar 2017 14:21:39 PST, just as I was about to take a herb,

> I would love to know the reason for this too! It has been known about
> for ages and I assume that if it were popular, it would have been done
> by now.

I assume you meant "... if it were POSSIBLE ...".
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Re: Can I boot from more than one GPT partition?

Postby mashedmitten » Fri Mar 10, 2017 12:08 pm

MBR disks all store the first part of the boot loader in the first sector and then hand off to the partition boot info. Just a guess, but one of the differences with GPT is that it stores boot data for all bootable partitions in multiple locations on the disk instead of the first sector, like MBR disks, and if one of those "becomes corrupted" Windows (don't know about other OS's) will automatically try to repair it. I can see where that would play havoc with a 3rd party boot loader. Also, the GUID string is so long, it's thought no two disks in the world would share the same ID. Guessing that may be a sticking point dev-wise, also.
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Re: Can I boot from more than one GPT partition?

Postby DrTeeth » Sat Mar 11, 2017 5:26 am

On Fri, 10 Mar 2017 10:40:06 PST, just as I was about to take a herb,
Bob Coleman disturbed my reverie and wrote:

>I assume you meant "... if it were POSSIBLE ...".

Sir, your presumption is indeed correct.

I must add another mark to my "senior moments" list, LOLZ.
--
Cheers,

DrT

"If you want to find out what is wrong
with democracy, spend five minutes with
the average voter." - Winston Churchill
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Re: Can I boot from more than one GPT partition?

Postby auryx » Tue Jan 01, 2019 6:09 am

Happy New Year all!

Sorry to perform "thread necromancy" on my old thread, but I spotted that BootIt UEFI is now released, and I was wondering if it now allowed booting from more than one GPT partition on the same drive? This remains my biggest (and only) gripe with BootIt BM.

Thanks! :-)
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Re: Can I boot from more than one GPT partition?

Postby TeraByte Support » Tue Jan 01, 2019 10:53 am

booting a GPT in UEFI mode works completely different than normal BIOS
booting. If in UEFI mode, you use BootIt UEFI, if in normal mode, than
BootIt BM. In UEFI, you can put the OS in different partitions, but they
will all boot through the EFI System partition.


"auryx" wrote in message news:16192@public.bootitbm...

Happy New Year all!

Sorry to perform "thread necromancy" on my old thread, but I spotted that
BootIt UEFI is now released, and I was wondering if it now allowed booting
from more than one GPT partition on the same drive? This remains my biggest
(and only) gripe with BootIt BM.

Thanks!

![:-)]({SMILIES_PATH}/icon_e_smile.gif)


TeraByte Support
 
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Re: Can I boot from more than one GPT partition?

Postby auryx » Sat Jan 05, 2019 10:42 am

Thanks TeraByte Support. Sorry for the delayed reply.

Unfortunately, I don't quite understand your answer. I understand the difference between BIOS booting and UEFI booting. However, the scenario I want to achieve is as follows:

- I have a 4TB disk drive
- The drive is formatted using GPT not MBR
- I have (say) 3 OS partitions on that drive
- Each partition has a different OS on it (for example, 3 different Linux distros)
- Each partition has a bootloader for that specific OS only, installed in that partition
- I wish to use BootIT BM (either version) to select any one of those 3 individual partitions to boot from, at system startup.

Does that make sense? Maybe my question is misguided because I don't understand the boot process correctly - happy to be corrected if so.

Thanks again in advance :-)
auryx
 
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Re: Can I boot from more than one GPT partition?

Postby TeraByte Support » Sat Jan 05, 2019 1:28 pm

you'd have to use UEFI to boot GPT using BIU.

Using BIBM, you use MBR/EMBR and normal BIOS to boot.

There is no hybrid booting.


"auryx" wrote in message news:16209@public.bootitbm...

Thanks TeraByte Support. Sorry for the delayed reply.

Unfortunately, I don't quite understand your answer. I understand the
difference between BIOS booting and UEFI booting. However, the scenario I
want to achieve is as follows:

- I have a 4TB disk drive
- The drive is formatted using GPT not MBR
- I have (say) 3 OS partitions on that drive
- Each partition has a different OS on it (for example, 3 different Linux
distros)
- Each partition has a bootloader for that specific OS only, installed in
that partition
- I wish to use BootIT BM (either version) to select any one of those 3
individual partitions to boot from, at system startup.

Does that make sense? Maybe my question is misguided because I don't
understand the boot process correctly - happy to be corrected if so.

Thanks again in advance

![:-)]({SMILIES_PATH}/icon_e_smile.gif)


TeraByte Support
 
Posts: 2737
Joined: Thu May 05, 2011 3:37 pm

Re: Can I boot from more than one GPT partition?

Postby Brian K » Sat Jan 05, 2019 4:16 pm

auryx wrote:
>
>
> - I have a 4TB disk drive
> - The drive is formatted using GPT not MBR
> - I have (say) 3 OS partitions on that drive
> - Each partition has a different OS on it (for example, 3 different Linux
> distros)
> - Each partition has a bootloader for that specific OS only, installed in
> that partition
> - I wish to use BootIT BM (either version)

Michael,

You can use BIU to boot as many Linux or Windows OS on that GPT disk as you desire but the OS must be installed with their booting files in the EFI System Partition. There will be a single EFI System Partition and it will contain booting files for all your OS. What you have at present won't work.
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Location: NSW, Australia

Re: Can I boot from more than one GPT partition?

Postby auryx » Sun Jan 06, 2019 2:49 am

Hi TeraByte and Brian,

Ok, many thanks for both your replies - that's clear to me now. Was hoping the answer would be otherwise but it's not the end of the world :-)

Thanks again!

Michael.
auryx
 
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