[grub2 newbie] Chainload grub-legacy from grub2

[grub2 newbie] Chainload grub-legacy from grub2

[Issac Goldstand]

Hi all,
  I am trying to use grub2 to boot from an iso image.  The iso is for a
live cd which in turn runs grub-legacy.  I've gotten the loopback
figured out (awesome feature!!!) but can't get the old grub-legacy to boot.

Currently, I do:
loopback cd (hd0,1)/path/to/image.iso
root=(cd)
chainloader +1

But I get
error: invalid signuature.

Am I missing something?

  Issac

(PS - I saw that initial gfxterm support is forthcoming.  Vesa++)

Re: [grub2 newbie] Chainload grub-legacy from grub2

[Marco Gerards]

Issac Goldstand <margol@beamartyr.net> writes:

Hi,

>   I am trying to use grub2 to boot from an iso image.  The iso is for a
> live cd which in turn runs grub-legacy.  I've gotten the loopback
> figured out (awesome feature!!!) but can't get the old grub-legacy to boot.
>
> Currently, I do:
> loopback cd (hd0,1)/path/to/image.iso
> root=(cd)
> chainloader +1
>
> But I get
> error: invalid signuature.
>
> Am I missing something?

Yeah, loopback should be used to boot by loading from the filesystem.
So if it is a GNU/Linux CDROM you can just load the kernel.  But in
that case the distribution should also understand this feature somehow
and mount the loopback image as well.

The problems with chainloading is that this might work differently for
CDROMs.  One thing is that you have to read 2048 bytes instead of
512.  Besides that, the code in this sector is not enough to boot the
CDROM usually and the boot code will not find the CDROM, because it is
not in the CDROM drive.

So in your case this feature is not as useful as it seemed to be, I
think.

--
Marco