Ubuntu server 14.04.3 can be installed only with EFI partition but I can't boot

Petter Adsen petter at synth.no
Tue Oct 27 09:35:34 UTC 2015


On Tue, 27 Oct 2015 08:13:13 +0200
Victor Sterpu <victor at casnt.ro> wrote:

> I created MSDOS partition table instead of GPT and this solved the problem.

Are you also booting in Legacy/BIOS mode now? (Some computers will fall
back to booting in Legacy mode if they fail to detect any UEFI
applications/bootloaders.) If so, you will be using grub-pc, which the
BIOS will find in the MBR. GPT has no MBR, so grub-efi needs to be
located in the ESP/EFI boot partition.

Check if the directory /sys/firmware/efi exists. If it doesn't exist,
then you are not booted in UEFI mode.

You also need to check that the correct GRUB package is installed, as
otherwise upgrades won't work correctly - grub-efi-amd64 (or
grub-efi-ia32 in some cases) for UEFI boot and grub-pc for Legacy.

https://wiki.archlinux.org/index.php/UEFI#Boot_Process_under_UEFI
https://help.ubuntu.com/community/UEFI

If you are indeed booting in Legacy mode, then you can get rid of the
EFI boot partition altogether, as it will not be needed. Hence, there
is no need to RAID it either. For *Legacy* mode, the boot disk does need
to have an MBR/MSDOS partition table, as GPT has no MBR. Most UEFI
implementations can boot from either, but there are some UEFI firmwares
that can only boot from a GPT disk.

> Manualy synchronizing the EFI partition would be a complication.

http://askubuntu.com/questions/66637/can-the-efi-system-partition-be-raided
https://wiki.archlinux.org/index.php/UEFI#ESP_on_RAID

"It is possible to make the ESP part of a RAID1 array, but doing so
brings the risk of data corruption, and further considerations need to
be taken when creating the ESP. See
https://bbs.archlinux.org/viewtopic.php?pid=1398710#p1398710 and
https://bbs.archlinux.org/viewtopic.php?pid=1390741#p1390741 for
details."

Besides, it's not a big complication. Set up a cron job as it can
easily be automated. Or just boot in Legacy mode if you don't need or
want UEFI and GPT.

> Do I have disavantages if I use MSDOS partition table?

Some. See:

https://wiki.archlinux.org/index.php/GPT#Problems_with_MBR
https://wiki.archlinux.org/index.php/GRUB2#UEFI_systems

"An EFI System Partition (ESP) is needed on every disc you want to boot
using EFI. GPT is not strictly necessary, but it is highly recommended
and is the only method currently supported in this article."

The most important limitations of the MBR/MSDOS partitioning scheme is
that you cannot define partitions beyond 2TiB, and that some UEFI
firmwares can't boot from MBR disks in UEFI mode.

As most of these articles I've linked to are written for Arch, you will
need to be careful if you choose to follow any of them, as some details
will be different for Ubuntu. I included them because they were the
most detailed technical references I could find for Linux.

Petter

> 
> On 26.10.2015 13:08, Petter Adsen wrote:
> > On Mon, 26 Oct 2015 12:26:07 +0200
> > Sergiu Mihuleac <mihuleac.sergiu at gmail.com> wrote:
> >  
> >> On what hdd is grub installed? Make sure bios boots from it. Second for dos
> >> you may need to recrete partition table, boot from an live usb with gpart
> >> and at device you will find create partition tabe then selec dos.  
> > The partition table type is completely irrelevant. The problem is that
> > the firmware does not understand mdadm RAID. You can either place the
> > EFI boot partition on a non-RAID partition, put it on a USB stick and
> > boot from that, or manually duplicate a non-RAID EFI boot partition to
> > the other disk and add UEFI boot entries for it with 'efibootmgr'.
> >
> > Petter
> >  
> >> On Oct 26, 2015 12:16 PM, "Petter Adsen" <petter at synth.no> wrote:
> >>  
> >>> On Mon, 26 Oct 2015 12:02:54 +0200
> >>> Victor Sterpu <victor at casnt.ro> wrote:
> >>>     
> >>>> Hello
> >>>>
> >>>> I installed Ubuntu server 14.04.3 a lot of times today.
> >>>> My setup is 2 HDD in RAID 1, /boot, root and swap partitions.
> >>>> If I install Ubuntu without a EFI partition I receive the error "This
> >>>> GPT partition label contains no BIOS Boot Partition" when grub installs
> >>>> and I can't boot.
> >>>>
> >>>> If I create a new partition of type EFI(RAID1) then grub install fine
> >>>> but I can't boot from the system.
> >>>> The Bios is in UEFI mode.
> >>>> How can I fix this?  
> >>> Put the EFI boot partition outside the RAID?
> >>>
> >>> Petter
> >>>
> >>> --
> >>> "I'm ionized"
> >>> "Are you sure?"
> >>> "I'm positive."
> >>>
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> >>> ubuntu-users mailing list
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> >
> >  
> 
> 



-- 
"I'm ionized"
"Are you sure?"
"I'm positive."



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