Bug#561294: core.img is unusually large, grub-pc fails to install grub mbr

[Felix Zielcke]

Am Donnerstag, den 17.12.2009, 14:30 -0700 schrieb Thomas Fjellstrom:
> On Fri December 18 2009, Miguel Landaeta wrote:
> > On Fri, Dec 18, 2009 at 4:08 PM, Thomas Fjellstrom
> <tfjellstrom at shaw.ca> 
> wrote:
> > > My core.img file is 31.13KB in size. Also the auto generated
> grub.conf
> > > seems to include a "raid" module that probably isn't needed? (it
> also
> > > includes mdraid and lvm) Is there a way I can remove it?
> > >
> > > And as I mentioned, I asked about this in the #grub channel on
> > > irc.freenode.net and they seemed to hint at the fact that debian's
> grub
> > > package is known to make the driver modules larger in size that
> stock
> > > grub does.
> > 
> > Ok, my core.img file was ~50KB so I had to repartition.
> > 
> > In your case, you could use grub-mkimage to generate a new core.img,
> >  remove some unused modules and see if you image can fit.
> > 
> 
> I'm not sure how to do that. I've run grub-mkimage and overwrote
> core.img 
> which gets me to a 20KB file, and grub-install overwrites it with a
> larger 
> 31KB file. Changing grub.cfg is impossible as update-grub overwrites
> that 
> every time. I can't see a reliable way of configuring grub2.

grub-install should only use the modules for core.img which are required
to access /boot/grub.
You can see the list with something like
bash -x grub-install /dev/sda 2>&1 ¦ grep core.img

-- 
Felix Zielcke
Proud Debian Maintainer and GNU GRUB developer