Using GRUB2 to access/change GRUB legacy partitions

Using GRUB2 to access/change GRUB legacy partitions

[Philip Rhoades]

People,

I have a Gateway LT30 netbook that I am using for on the road that does 
everything I want:

- WiFi

- Broadband Wireless

with Fedora 13 - except:

- sound input is a problem (maybe it is a faulty microphone but I am not 
sure

- F13 is a bit slow on this little computer

so I have been checking out LOTS of the other distros.  F13 uses GRUB 
legacy.  Most of the other distros have a problem either installing or 
actually running and some use GRUB2.  GRUB2 imports all the setup stuff 
I have for GRUB legacy on F13 (/dev/sda1) but if I want to simply delete 
the new distro from it's partition and go back to F13 with GRUB legacy, 
I have to boot on an F13 Live CD and run GRUB from a shell to reset the 
system to boot from the /dev/sda1 (hd0,0) partition.  After doing this a 
lot I am wondering if there isn't an easier way of doing it?  Shouldn't 
I be able to restore the original setup from the newly installed distro 
running GRUB2?  (I have Googled and looked through the GRUB mail archives).

Thanks,

Phil.
-- 
Philip Rhoades

GPO Box 3411
Sydney NSW	2001
Australia
E-mail:  phil@pricom.com.au

GRUB2 facility to boot ISOs?

[Philip Rhoades]

People,

I started this thread quite a while ago (I have asked LQ why it has 
another user's name on it):

http://www.linuxquestions.org/questions/linux-software-2/booting-of-raw-iso-from-grub-lilo-though-preferably-grub-367901/

but haven't ever gotten a workable response.  I realise that ISOs from 
different distros are set up differently but is it a feasible/desirable 
feature to think about for GRUB2?

Thanks,

Phil.
-- 
Philip Rhoades

GPO Box 3411
Sydney NSW	2001
Australia
E-mail:  phil@pricom.com.au

Re: Using GRUB2 to access/change GRUB legacy partitions

[Vladimir 'φ-coder/phcoder' Serbinenko]

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Philip Rhoades wrote:
> People,
>
> I have a Gateway LT30 netbook that I am using for on the road that
> does everything I want:
>
> - WiFi
>
> - Broadband Wireless
>
> with Fedora 13 - except:
>
> - sound input is a problem (maybe it is a faulty microphone but I am
> not sure
>
> - F13 is a bit slow on this little computer
>
> so I have been checking out LOTS of the other distros.  F13 uses GRUB
> legacy.  Most of the other distros have a problem either installing or
> actually running and some use GRUB2.  GRUB2 imports all the setup
> stuff I have for GRUB legacy on F13 (/dev/sda1) but if I want to
> simply delete the new distro from it's partition and go back to F13
> with GRUB legacy, I have to boot on an F13 Live CD and run GRUB from a
> shell to reset the system to boot from the /dev/sda1 (hd0,0)
> partition.  After doing this a lot I am wondering if there isn't an
> easier way of doing it?  Shouldn't I be able to restore the original
> setup from the newly installed distro running GRUB2?  (I have Googled
> and looked through the GRUB mail archives).
>
This isn't a tech support list. Please use help-grub@gnu.org or IRC #grub.
> Thanks,
>
> Phil.


-- 
Regards
Vladimir 'φ-coder/phcoder' Serbinenko



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Re: GRUB2 facility to boot ISOs?

[Colin Watson]

On Tue, May 18, 2010 at 05:12:17PM +1000, Philip Rhoades wrote:
> I started this thread quite a while ago (I have asked LQ why it has  
> another user's name on it):
>
> http://www.linuxquestions.org/questions/linux-software-2/booting-of-raw-iso-from-grub-lilo-though-preferably-grub-367901/
>
> but haven't ever gotten a workable response.  I realise that ISOs from  
> different distros are set up differently but is it a feasible/desirable  
> feature to think about for GRUB2?

GRUB is entirely capable of reading the kernel and initrd from an ISO
using its loopback module, but after that the OS starts up with
basically bare metal and a set of command-line arguments, and it's up to
it to figure out how to mount its root filesystem.  There's no way for
GRUB to give it any more help than it already does.

(That said, we've talked about trying to establish a standard whereby an
OS can advertise to GRUB that it supports this so that appropriate
configuration stanzas can be generated automatically, and this may
happen.)

-- 
Colin Watson                                       [cjwatson@ubuntu.com]

Re: GRUB2 facility to boot ISOs?

[Frombenny]

Here's an example to launch an iso of gpartedlivecd from Grub2. I always 
add it on my 40_custom file :

menuentry "ISO Live - GParted Live" {
insmod loopback
insmod iso9660
set isofile="/iso/gparted-live-0.5.2-1.iso"
loopback loop (hd0,5)$isofile
set gfxpayload=800x600x16, 800x600
linux (loop)/live/vmlinuz locale=fr_FR keyb=fr console-setup/layoutcode=fr gl_kbd=fr gl_lang=fr_FR gl_numlk=off gl_batch boot=live union=aufs noswap noprompt ip=frommedia toram=filesystem.squashfs findiso=$isofile
initrd (loop)/live/initrd.img
}

There are others examples on this page : 
http://doc.ubuntu-fr.org/tutoriel/grub2_lancer_des_images_iso

You can use the soft here : http://liveusb.info/ to launch one or more 
iso(s) from an USB key.

In short, Grub2 have made a great job yet.. Now to spread it, it depends 
on linux distributions to implement it in their isos.

Benoit

Le 18/05/2010 09:12, Philip Rhoades a écrit :
> People,
>
> I started this thread quite a while ago (I have asked LQ why it has 
> another user's name on it):
>
> http://www.linuxquestions.org/questions/linux-software-2/booting-of-raw-iso-from-grub-lilo-though-preferably-grub-367901/ 
>
>
> but haven't ever gotten a workable response.  I realise that ISOs from 
> different distros are set up differently but is it a 
> feasible/desirable feature to think about for GRUB2?
>
> Thanks,
>
> Phil.