Re: Linux and Windows Disk Drive imaging

On a sunny day (Wed, 2 Dec 2009 17:58:46 -0800) it happened
dplatt@xxxxxxxxxxxx (Dave Platt) wrote in <mjiju6-5pg.ln1@xxxxxxxxxxxx>:


In article <PpDRm.72639$mn3.16186@xxxxxxxxxxxxxxxxxxxxxxxxxxx>,
Joel Koltner <zapwireDASHgroups@xxxxxxxxx> wrote:
Thanks Dave; that's a reasonably simple approach. One last question: Is /grub
part of the "regular old file system" on a given partition (i.e., menu.lst,
etc. are stored within your, say, ext2 filesystem just like any other file),
or is it a special filesystem that GRUB understands but that actually occupies
parts of a partition separate from the rest of your files?

The former.

The only part of GRUB which isn't part of a normal filesystem, is the
boot-sector itself - the very first level. The later stages are all
stored in a standard filesystem.

I ask in that it's never been clear to me how, if menu.lst, etc. are all just
regular files, GRUB manages to access them since first it would have to be
able to find the ext2 or ext3 or reiserfs or jfs or a myriad of other
filesystem driver, which seems like a chick-and-egg problem.

When you run "install-grub", the installer asks your filesystem code
(e.g. ext2) where the later-stage loading files are (that is, their
actual sector offsets within the filesystem partition in which they
live). Specifically, it needs to know where "stage1" is, and the
"stage1_5" files for any filesystem formats you may need to use to
locate your kernel. I'm not sure whether it needs to know where
"stage2" is.

'grub-install' may fail o nsome systems, cant remember teh reason,
but you can start grub manually ,and enter the commands.
Here is the kernel-howto I wrote for myself, grub install on variuos media is at the end.
This works, as I have compiled and installed many kernels on this system using that. howto.
It was once intended to be a script, but bette just read it.. and do it manually.


Kernel update howto copyright Jan Panteltje 2009-always, released under GPL2


# Instructions how to update kernel

Change the link in /usr/src for 'linux' to point to the new kernel with rm linux;ln -s new-kernel linux.

cd /usr/src/linux


# UPDATE DVB DRIVER (only if you use xdipo and associated software for satellite).
joe /usr/src/linux/drivers/media/dvb/dvb-core/dmxdev.h
# change #define DVR_BUFFER_SIZE (10*188*1024) to:
# #define DVR_BUFFER_SIZE (100*188*1024)


#SAVE THE .config file!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
cp .config .config.LAST


make mrproper

### SELECT xterm, NOT rxvt, else config crashes!!!!!!
### Use ctl BACKSPACE for backspace

make menuconfig

Load latest config from /root/kernel/

cp .config NEW_CONFIG_XXXX

make
make modules_install


# Copy image and map
#mv /boot/vmlinuz-$1 /boot/vmlinuz-$1.old
#cp /usr/src/linux/arch/i386/boot/bzImage /boot/vmlinuz-$1
#cp /usr/src/linux/System.map /boot/System.map-$1

# for boot with grub from ext2 on hdc6
mount /dev/hdd6 /mnt/hdd6
cp /usr/src/linux/arch/i386/boot/bzImage /mnt/hdd6/vmlinuz-$1
cp /usr/src/linux/System.map /mnt/hdd6/System.map-$1

umount /dev/hdd6


# Test new kernel like this from grub command line:
# >kernel (hd2,5)/vmlinuz-XXXXXX root=/dev/hdc7
# >boot


# Make a grub boot CD-RW or DVD+RW
#joe iso/boot/grub/menu.lst
cd
mkdir -p iso/boot/grub
cp /lib/grub/i386-pc/stage2_eltorito iso/boot/grub
mkisofs -R -b boot/grub/stage2_eltorito -no-emul-boot -boot-load-size 4 -boot-info-table -o grub.iso iso
ls -rtl *.iso
#burn-cd-image grub.iso
# Use a DVD-RW
burn-dvd-image grub.iso


# Installing grub to hda:
#Copy all grub files, including stage1 and stage2 to /mny/hda1/boot/grub

#mount /dev/hda1 /mnt/hda1
#hdparm -d 1 /dev/hda
mkdir -p /dev/hda1/boot/grub

#mount /dev/hdb3 /mnt/hdb3
#hdparmn -d 1 /dev/hdb

########cp -ip /mnt/hdb3/lib/grub/i386-pc/* /mnt/hda1/
#cp -ip /root/kernel/boot-grub/* /mnt/fd0/boot/grub/

#Install manually from the Grub shell with:
grub
#root (hd0,0)
#setup (hd0)
#quit

#umount /dev/hda1
#umount /dev/hdb3
#hdparm -Y /dev/hda
#hdparm -Y /dev/hdb


# Maing a grub boot floppy
#mke2fs /dev/fd0
#mount /dev/fd0 /mnt/fd0
#mkdir -p /mnt/fd0/boot/grub
######cp -ip /mnt/hdb3/lib/grub/i386-pc/* /mnt/fd0/boot/grub/
#cp -ip /root/kernel/boot-grub/* /mnt/fd0/boot/grub/
#device (fd0) /dev/fd0
#grub
## in gub type
#root (fd0)
#setup (fd0)
#quit


.

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