Booting to local disk from UEFI_PXE booted grub

Booting to local disk from UEFI_PXE booted grub

[Holger Goetz]

Hi all,

I'm looking for the equivalent of "Local boot / boot from HD" for BIOS 
mode when running in grub stared in UEFI-PXE.

With (U)EFI it's no longer easy to say, "boot from HD" as there could be 
multiple bootloaders present on the EFI  System Partition (ESP).  
Basically only the UEFI boot system knows which one to boot from the 
"Bootorder" or "Bootnext" EFI Variable(s).
Any approach ? Or is there a way to access these EFI variables from the 
grub config file?

Thanks,
Holger

Re: Booting to local disk from UEFI_PXE booted grub

[Andrey Borzenkov]

On Mon, Nov 18, 2013 at 12:33 PM, Holger Goetz <holgerg@hgsys.de> wrote:
> Hi all,
>
> I'm looking for the equivalent of "Local boot / boot from HD" for BIOS mode
> when running in grub stared in UEFI-PXE.
>
> With (U)EFI it's no longer easy to say, "boot from HD" as there could be
> multiple bootloaders present on the EFI  System Partition (ESP).  Basically
> only the UEFI boot system knows which one to boot from the "Bootorder" or
> "Bootnext" EFI Variable(s).

If you exit grub EFI firmware should continue with next boot menu
entry. Would it be OK for you?

> Any approach ? Or is there a way to access these EFI variables from the grub
> config file?
>
> Thanks,
> Holger
>
>
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> https://lists.gnu.org/mailman/listinfo/grub-devel

Re: Booting to local disk from UEFI_PXE booted grub

[Holger Goetz]

On 20.11.2013 16:18, Andrey Borzenkov wrote:
> On Mon, Nov 18, 2013 at 12:33 PM, Holger Goetz <holgerg@hgsys.de> wrote:
>> Hi all,
>>
>> I'm looking for the equivalent of "Local boot / boot from HD" for BIOS mode
>> when running in grub stared in UEFI-PXE.
>>
>> With (U)EFI it's no longer easy to say, "boot from HD" as there could be
>> multiple bootloaders present on the EFI  System Partition (ESP).  Basically
>> only the UEFI boot system knows which one to boot from the "Bootorder" or
>> "Bootnext" EFI Variable(s).
> If you exit grub EFI firmware should continue with next boot menu
> entry. Would it be OK for you?

Hi Andrey,

yes, thanks, i figured in the meantime that it looks like the is the 
best option to do.

Have dropped ideas to write a module that adds a command to read (U)EFI 
environment variables like "BootOrder". Although reading (U)EFI EVs 
might be handy in other use cases, and base functionality is already 
available, just not as a command.

Thanks,
Holger

>> Any approach ? Or is there a way to access these EFI variables from the grub
>> config file?
>>
>> Thanks,
>> Holger
>>
>>
>> _______________________________________________
>> Grub-devel mailing list
>> Grub-devel@gnu.org
>> https://lists.gnu.org/mailman/listinfo/grub-devel
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> https://lists.gnu.org/mailman/listinfo/grub-devel
>
>

Re: Booting to local disk from UEFI_PXE booted grub

[Vladimir 'φ-coder/phcoder' Serbinenko]

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On 18.11.2013 09:33, Holger Goetz wrote:
> Hi all,
> 
> I'm looking for the equivalent of "Local boot / boot from HD" for BIOS
> mode when running in grub stared in UEFI-PXE.
> 
> With (U)EFI it's no longer easy to say, "boot from HD" as there could be
> multiple bootloaders present on the EFI  System Partition (ESP). 
> Basically only the UEFI boot system knows which one to boot from the
> "Bootorder" or "Bootnext" EFI Variable(s).
> Any approach ? Or is there a way to access these EFI variables from the
> grub config file?
> 
I would just show menu entries for every available /EFI/*/*.EFI. This
woud add more flexibility.
> Thanks,
> Holger
> 
> 
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> https://lists.gnu.org/mailman/listinfo/grub-devel
> 



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Re: Booting to local disk from UEFI_PXE booted grub

[Holger Goetz]

On 20.11.2013 16:53, Vladimir 'φ-coder/phcoder' Serbinenko wrote:
> On 18.11.2013 09:33, Holger Goetz wrote:
>> Hi all,
>>
>> I'm looking for the equivalent of "Local boot / boot from HD" for BIOS
>> mode when running in grub stared in UEFI-PXE.
>>
>> With (U)EFI it's no longer easy to say, "boot from HD" as there could be
>> multiple bootloaders present on the EFI  System Partition (ESP).
>> Basically only the UEFI boot system knows which one to boot from the
>> "Bootorder" or "Bootnext" EFI Variable(s).
>> Any approach ? Or is there a way to access these EFI variables from the
>> grub config file?
>>
> I would just show menu entries for every available /EFI/*/*.EFI. This
> woud add more flexibility.
Hi Vladimir,

Is there easy way of doing this?
That was one idea in mind which could be done based on the info from the 
(U)EFI EVs to be displayed. Or it means to (1) search for the files and 
(2) dynamically puzzle together a (sub) menu i guess.

Thanks,
Holger

Re: Booting to local disk from UEFI_PXE booted grub

[Vladimir 'φ-coder/phcoder' Serbinenko]

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On 20.11.2013 16:58, Holger Goetz wrote:
> On 20.11.2013 16:53, Vladimir 'φ-coder/phcoder' Serbinenko wrote:
>> On 18.11.2013 09:33, Holger Goetz wrote:
>>> Hi all,
>>>
>>> I'm looking for the equivalent of "Local boot / boot from HD" for BIOS
>>> mode when running in grub stared in UEFI-PXE.
>>>
>>> With (U)EFI it's no longer easy to say, "boot from HD" as there could be
>>> multiple bootloaders present on the EFI  System Partition (ESP).
>>> Basically only the UEFI boot system knows which one to boot from the
>>> "Bootorder" or "Bootnext" EFI Variable(s).
>>> Any approach ? Or is there a way to access these EFI variables from the
>>> grub config file?
>>>
>> I would just show menu entries for every available /EFI/*/*.EFI. This
>> woud add more flexibility.
> Hi Vladimir,
> 
> Is there easy way of doing this?
> That was one idea in mind which could be done based on the info from the
> (U)EFI EVs to be displayed. Or it means to (1) search for the files and
> (2) dynamically puzzle together a (sub) menu i guess.
> 
Have a look at autoiso.cfg and osdetect.cfg for how to find files.
> Thanks,
> Holger
> 



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Re: Booting to local disk from UEFI_PXE booted grub

[Holger Goetz]

On 20.11.2013 17:03, Vladimir 'φ-coder/phcoder' Serbinenko wrote:
> On 20.11.2013 16:58, Holger Goetz wrote:
>> On 20.11.2013 16:53, Vladimir 'φ-coder/phcoder' Serbinenko wrote:
>>> On 18.11.2013 09:33, Holger Goetz wrote:
>>>> Hi all,
>>>>
>>>> I'm looking for the equivalent of "Local boot / boot from HD" for BIOS
>>>> mode when running in grub stared in UEFI-PXE.
>>>>
>>>> With (U)EFI it's no longer easy to say, "boot from HD" as there could be
>>>> multiple bootloaders present on the EFI  System Partition (ESP).
>>>> Basically only the UEFI boot system knows which one to boot from the
>>>> "Bootorder" or "Bootnext" EFI Variable(s).
>>>> Any approach ? Or is there a way to access these EFI variables from the
>>>> grub config file?
>>>>
>>> I would just show menu entries for every available /EFI/*/*.EFI. This
>>> woud add more flexibility.
>> Hi Vladimir,
>>
>> Is there easy way of doing this?
>> That was one idea in mind which could be done based on the info from the
>> (U)EFI EVs to be displayed. Or it means to (1) search for the files and
>> (2) dynamically puzzle together a (sub) menu i guess.
>>
> Have a look at autoiso.cfg and osdetect.cfg for how to find files.
Yes - thanks. Checked that - it could be a way.

The drawback is that it basically bypasses the (U)EFI bootsystem w/ the 
bootorder and the labels stored w/ each bootloader entry.  By retrieving 
the (U)EFI EVs (1) the proper sequence and (2) the proper labeling  
could be represented in the menu entries as well.

eg. in the default path you could find /efi//boot/bootx64.efi which 
could be a microsoft windows boot loader OR a renamed grub.efi ... 
clearer when it's a non default path like /efi/SuSE/elilo.efi or 
/efi/redhat/grub.efi. But you still would guess on the OS name SLES11sp3 
or sp5? Having the info from the (U)EFI  EVs this would be clear.

Thanks,
Holger

>> Thanks,
>> Holger
>>
>
>
>
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
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