source: npl/system/grub/syn3-install-grub @ b4abfab

#!/bin/bash
#syn-3 grub installer (C)DatuX
#Fully automaticly install grub in the MBR of all discs in /dev/md0


#mount boot als hij nog niet gemount is
mount /boot
ERR=$?
[ "$ERR" != "0" ] && [ "$ERR" != "32" ] && exit 1

#kopieer eenmalig, zorg dat stage2 NOOIT meer veranderd
#ivm secondary DRBD node!
if ! [ -f /boot/grub/stage2 ]; then
        mkdir /boot/grub &>/dev/null
        cp -a /usr/lib/grub/i386-pc/* /boot/grub || exit 1
fi

#bepaal welke partities we hebben in onze boot raid array md0
PARTS=`
    mdadm --detail /dev/md0|
    grep -v /dev/md0|
    grep /dev|
    sed 's#^[^/]*##g' #remove spaces
` || exit 1


#bepaal bijbehorende discs
for PART in $PARTS; do
        DISCS="$DISCS `getdisk $PART`"
done

#unmount boot, omdat grub de schijf rechstreeks benaderd
umount /boot || exit 1

#installeer grub
touch /tmp/device.map
ERROR=
for DISC in $DISCS; do
    echo "Installing grub on $DISC..."
    echo -e "device (hd0) $DISC\nroot (hd0,0)\nsetup (hd0)\nquit" > /tmp/grub.$$ 
    if ! grub --device-map=/tmp/device.map --batch < /tmp/grub.$$ ; then
        echo error
        ERROR=1
    fi
done
rm /tmp/grub.$$

#mount boot weer
mount /boot || exit 1

#default keuze is normaal 0
grub-set-default 0 || exit 1

[ "$ERROR" ] && exit 1

exit 0