Плавный переход с Ubuntu на Gentoo

mkdir /mnt/ubutnu
mount /dev/disk/by-label/ubuntu /mnt/ubutntu
ls -l /dev/disk/by-uuid
ls -l /dev/disk/by-label
nano -w /mnt/ubuntu/fstab

mount -t proc none /mnt/ubuntu/proc
mount --rbind /dev /mnt/ubuntu/dev
chroot /mnt/ubuntu

mkdir /media/boot
mount /dev/disk/by-label/boot /media/boot
grub-install --boot-directory=/media/boot /dev/sda

cp /boot/vmlinuz-3.0.0-14-generic \
   /boot/vmcoreinfo-3.0.0-14-generic \
   /boot/System.map-3.0.0-14-generic \
   /boot/initrd.img-3.0.0-14-generic \
   /boot/abi-3.0.0-14-generic \
   /boot/config-3.0.0-14-generic \
   /boot/memtest86+.bin \
   /boot/memtest86+_multiboot.bin \
   /media/boot/
mv /boot /boot.old
mkdir /boot
umount /media/boot
mount /dev/disk/by-label/boot /boot

update-grub

tar xvjpf stage3-*.tar.bz2
tar xvjf /mnt/gentoo/portage-latest.tar.bz2 -C /mnt/gentoo/usr

# /boot/grub/grub.cfg

### BEGIN /etc/grub.d/00_header ###
if [ -s $prefix/grubenv ]; then
  set have_grubenv=true
  load_env
fi
set default="0"
if [ "${prev_saved_entry}" ]; then
  set saved_entry="${prev_saved_entry}"
  save_env saved_entry
  set prev_saved_entry=
  save_env prev_saved_entry
  set boot_once=true
fi

function savedefault {
  if [ -z "${boot_once}" ]; then
    saved_entry="${chosen}"
    save_env saved_entry
  fi
}

function recordfail {
  set recordfail=1
  if [ -n "${have_grubenv}" ]; then if [ -z "${boot_once}" ]; then save_env recordfail; fi; fi
}

function load_video {
  insmod vbe
  insmod vga
  insmod video_bochs
  insmod video_cirrus
}

insmod part_msdos
insmod ext2
set root='(hd0,msdos7)'
search --no-floppy --fs-uuid --set=root e12efc8c-8057-4a14-bdf0-448e26437e77
if loadfont /usr/share/grub/unicode.pf2 ; then
  set gfxmode=auto
  load_video
  insmod gfxterm
  insmod part_msdos
  insmod ext2
  set root='(hd0,msdos1)'
  search --no-floppy --fs-uuid --set=root aec1d4c6-8332-46b8-a024-244e5fa90df4
  set locale_dir=($root)/grub/locale
  set lang=ru_RU
  insmod gettext
fi
terminal_output gfxterm
if [ "${recordfail}" = 1 ]; then
  set timeout=-1
else
  set timeout=3
fi
### END /etc/grub.d/00_header ###

### BEGIN /etc/grub.d/05_debian_theme ###
set menu_color_normal=white/black
set menu_color_highlight=black/light-gray
if background_color 44,0,30; then
  clear
fi
### END /etc/grub.d/05_debian_theme ###

### BEGIN /etc/grub.d/10_linux ###
if [ ${recordfail} != 1 ]; then
  if [ -e ${prefix}/gfxblacklist.txt ]; then
    if hwmatch ${prefix}/gfxblacklist.txt 3; then
      if [ ${match} = 0 ]; then
        set linux_gfx_mode=keep
      else
        set linux_gfx_mode=text
      fi
    else
      set linux_gfx_mode=text
    fi
  else
    set linux_gfx_mode=keep
  fi
else
  set linux_gfx_mode=text
fi
export linux_gfx_mode
if [ "$linux_gfx_mode" != "text" ]; then load_video; fi
menuentry 'Ubuntu, с Linux 3.0.0-14-generic' --class ubuntu --class gnu-linux --class gnu --class os {
        recordfail
        set gfxpayload=$linux_gfx_mode
        insmod gzio
        insmod part_msdos
        insmod ext2
        set root='(hd0,msdos1)'
        search --no-floppy --fs-uuid --set=root aec1d4c6-8332-46b8-a024-244e5fa90df4
        linux   /vmlinuz-3.0.0-14-generic root=UUID=e12efc8c-8057-4a14-bdf0-448e26437e77 ro   quiet splash vt.handoff=7
        initrd  /initrd.img-3.0.0-14-generic
}
menuentry 'Ubuntu, с Linux 3.0.0-14-generic (режим восстановления)' --class ubuntu --class gnu-linux --class gnu --class os {
        recordfail
        insmod gzio
        insmod part_msdos
        insmod ext2
        set root='(hd0,msdos1)'
        search --no-floppy --fs-uuid --set=root aec1d4c6-8332-46b8-a024-244e5fa90df4
        echo    'Загружается Linux 3.0.0-14-generic ...'
        linux   /vmlinuz-3.0.0-14-generic root=UUID=e12efc8c-8057-4a14-bdf0-448e26437e77 ro recovery nomodeset
        echo    'Загружается начальный ramdisk ...'
        initrd  /initrd.img-3.0.0-14-generic
}
### END /etc/grub.d/10_linux ###

### BEGIN /etc/grub.d/20_linux_xen ###
### END /etc/grub.d/20_linux_xen ###

### BEGIN /etc/grub.d/20_memtest86+ ###
menuentry "Memory test (memtest86+)" {
        insmod part_msdos
        insmod ext2
        set root='(hd0,msdos1)'
        search --no-floppy --fs-uuid --set=root aec1d4c6-8332-46b8-a024-244e5fa90df4
        linux16 /memtest86+.bin
}
menuentry "Memory test (memtest86+, serial console 115200)" {
        insmod part_msdos
        insmod ext2
        set root='(hd0,msdos1)'
        search --no-floppy --fs-uuid --set=root aec1d4c6-8332-46b8-a024-244e5fa90df4
        linux16 /memtest86+.bin console=ttyS0,115200n8
}
### END /etc/grub.d/20_memtest86+ ###

### BEGIN /etc/grub.d/30_os-prober ###
menuentry "Gentoo" --class gnu-linux --class gnu --class os {
        insmod part_msdos
        insmod ext2
        set root='(hd0,msdos1)'
        linux /gentoo-2.6.38-tuxonice root=/dev/sda6 resume=swap:/dev/sda1
}
### END /etc/grub.d/30_os-prober ###

### BEGIN /etc/grub.d/40_custom ###
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
### END /etc/grub.d/40_custom ###

### BEGIN /etc/grub.d/41_custom ###
if [ -f  $prefix/custom.cfg ]; then
  source $prefix/custom.cfg;
fi
### END /etc/grub.d/41_custom ###