Can I boot from more than one GPT partition?

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auryx
Posts: 15
Joined: Sat Mar 19, 2016 12:49 pm

Can I boot from more than one GPT partition?

Post by auryx »

Hi folks,

My BIBM install usually "just works" in perfect fashion, but I'm having trouble achieving something today and I wonder if it's not possible.

One of my many HDDs (HDD 3) is 4TB in size and so formatted as GPT. Currently, I use BIBM to boot from an Arch Linux install (Syslinux bootloader) on partition 1. In the BIBM boot edit screen, the entry just points to HDD3, and the "boot" field is blank. This works fine.

I've now installed Ubuntu into partition 2 on the same HDD. I want to add a new boot entry to BIBM, such that I can boot directly to that partition on the GPT drive, separately of the original Arch Linux install. But I can't work out how to do it. The boot menu won't let me specify a GPT partition to boot from; seems it's the whole disk or nothing.

Am I missing something? :?

Thanks!

Michael.
mashedmitten
Posts: 151
Joined: Sun Dec 04, 2016 2:16 am

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

Post by mashedmitten »

When I set up a couple of Linux OS's, I installed GRUB to it's own partition, set BIBM to boot to it and then GRUB took over to get to the Linux OS.
auryx
Posts: 15
Joined: Sat Mar 19, 2016 12:49 pm

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

Post by auryx »

Thanks for the reply. Yes, I've just configured my Arch Linux Syslinux bootloader to be able to chainload GRUB for Ubuntu, so I can get to it that way - i.e. use BIBM to boot the Arch partition, which loads Syslinux, from which I select the Ubuntu partition, which loads GRUB, which loads Ubuntu. It works, but it's pretty clunky :-)

What I really want to do is be able to boot directly to the Ubuntu partition from BIBM, and I don't appear to be able to do that (or haven't managed to figure it out). Any ideas?

Michael.
CyberSimian
Posts: 137
Joined: Wed Aug 10, 2016 12:13 pm

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

Post by CyberSimian »

auryx wrote:
> What I really want to do is be able to boot directly to the Ubuntu
> partition from BIBM, and I don't appear to be able to do that (or haven't
> managed to figure it out). Any ideas?

As I understand it, BIBM cannot multi-boot GPT partitions. This is a capability that many BIBM users would like, but which does not yet exist. See this thread:

http://www.terabyteunlimited.com/ucf/vi ... f=2&t=2082

The workaround? Consign your 4 TB drive to the trash can and buy two 2 TB drives. Configure those drives to use MBR partition tables. I purchased a new laptop last year, which I have converted from UEFI/GPT to EMBR so that I can multiboot operating systems, but (of course) I won't be installing a 4 TB disk in the laptop anytime soon!

-- from CyberSimian in the UK
DrTeeth
Posts: 1289
Joined: Fri Aug 12, 2011 6:58 pm

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

Post by DrTeeth »

On Sat, 4 Mar 2017 01:34:00 PST, just as I was about to take a herb,
CyberSimian disturbed my reverie and wrote:

>As I understand it, BIBM cannot multi-boot GPT partitions.

I am not sure if that is the case or it cannot be installed on the
wanted drive. I am sure that if this were fixable, David would have
fixed it by now. I will never have GPT drives because of this. I do
not know if one has BIBM installed on the first (and MBR) drive, it
can be used to swap partitions on a GPT data drive. Until 2TB drives
become obsolete, I'll be okay*

*Until I upgrade my MB and CPU in a couple of months and find that the
mouse or some such things decides not to work/.
--
Cheers,

DrT

"If you want to find out what is wrong
with democracy, spend five minutes with
the average voter." - Winston Churchill
auryx
Posts: 15
Joined: Sat Mar 19, 2016 12:49 pm

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

Post by auryx »

Thanks all.

I don't want to throw away my 4TB drive, having only recently purchased it, and besides, that would seem like a step backwards :-) But I appreciate the advice. It's good to know others are in the same position.

If it is indeed the case that BIBM cannot multi-boot from GPT drives, I'd be curious to know why - it's a pity and it cripples my use of the product somewhat. If the Linux boot loader on the disk boot sector (vague term used to cover my ignorance....) can successfully chainload different boot loaders in the GPT partitions, why can't BIBM just replicate the same functionality? Maybe I need to do some googling on this to understand if it's a wider GPT limitation rather than a missing feature of the product.

Cheers,

Michael.
George
Posts: 38
Joined: Tue Aug 30, 2011 5:28 pm

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

Post by George »

Auryx,
You don't have to throw away your new 4TB drive just because it doesn't
work in your laptop.
Presently, I have a 2TB drive that I installed in an external drive
enclosure. Using IFL, I back up various computers to that drive. All
you have to do is make sure you can use the fastest connection between
devices. My enclosure has both eSATA and USB connections. I use the
eSATA connection for all but one computer so the cable transfer rate is
not the bottleneck.
Your GPT-enabled drive should work perfectly, as long as your bios can
handle GPT drives.

George
---
There are 10 kinds of people in the world.
Those who understand binary and
Those who don't.
auryx
Posts: 15
Joined: Sat Mar 19, 2016 12:49 pm

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

Post by auryx »

Thanks George.

My plan for my 4TB drive was to run many different OSes on it, each one bootable separately from BIBM. Unfortunately, it seems that is unworkable due to BIBM limitations on GPT....however, I'll just chainload all the other boot loaders from the primary one, so it's clunky but not the end of the world :-)

Anyone from Terabyte able to explain the limitation with GPT multiboot and suggest if it will ever be possible in future product versions?

Cheer,s

Michael.
CyberSimian
Posts: 137
Joined: Wed Aug 10, 2016 12:13 pm

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

Post by CyberSimian »

auryx wrote:
> My plan for my 4TB drive was to run many different OSes on it, each one
> bootable separately from BIBM. Unfortunately, it seems that is unworkable
> due to BIBM limitations on GPT....however, I'll just chainload all the
> other boot loaders from the primary one, so it's clunky but not the end of
> the world :-)

I have never chainloaded bootloaders, so I don't know how usable that will be. But if it turns out to be too inconvenient or error prone, another solution would be to retain your 4 TB drive, but partition it as MBR/EMBR, which would limit you to 2 TB. You should be able to use BIBM to multiboot, and you would not have to purchase any new hardware (but obviously you would not be getting full value out of your 4 TB drive).

-- from CyberSimian in the UK
DrTeeth
Posts: 1289
Joined: Fri Aug 12, 2011 6:58 pm

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

Post by DrTeeth »

On Thu, 9 Mar 2017 14:21:39 PST, just as I was about to take a herb,
auryx disturbed my reverie and wrote:

>Anyone from Terabyte able to explain the limitation with GPT multiboot and suggest if it will ever be possible in future product versions?

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.

TBH, I'll be long gone before I need a drive larger than 2GB.
--
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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