grub.cfg of multi-bootable disk.

grub.cfg

# ============================================================
#  Author: 凍仁翔 / chusiang.lai (at) gmail.com
#  Blog: http://note.drx.tw
#  Filename: grub.cfg
#  Modified: 2015-01-14 23:05
#  Description: grub configure of multi-bootable disk.
#
#   Now, we can boot with:
#    * Try Ubuntu 14.04.1 Desktop (EFI)
#    * Try Ubuntu 12.04.5 Desktop (EFI)
#    * Install Ubuntu 14.04.1 Desktop (EFI)
#    * Install Ubuntu 14.04.1 Server
#    * Install Ubuntu 12.04.5 Desktop (EFI)
#    * Install Ubuntu 12.04.5 Server
#    * Install Debian 7.7
#
#  Reference: 
#
#   * 自製 Ubuntu 13.04/12.10/12.04.2 與 Debian 7.0 測試硬體安裝使用的 USB 隨身碟 | FourDollars
#     - http://fourdollars.blogspot.tw/2013/05/ubuntu-1304121012042-debian-70-usb.html
#   * grub.cfg | fourdollars
#     - https://gist.github.com/fourdollars/5479632
#
# =========================================================== 

function load_efi_video {
    set gfxmode=auto
    insmod efi_gop
    insmod efi_uga
    insmod gfxterm
    terminal_output gfxterm
}

function load_video {
    set gfxmode=auto
    insmod vbe
    insmod vga
    insmod video_bochs
    insmod video_cirrus
    insmod gfxterm
    terminal_output gfxterm
}

if loadfont ($root)/boot/grub/fonts/unicode.pf2 ; then
    if load_efi_video ; then
        set bios="UEFI BIOS"
    else
        load_video
        set bios="Legacy BIOS"
    fi
fi

set locale_dir=($root)/boot/grub/locale
set lang=en_US
insmod gettext

set menu_color_normal=white/black
set menu_color_highlight=black/light-gray
if background_color 44,0,30; then
    clear
fi


# Try
######

menuentry "Try Ubuntu 14.04.1 Desktop (EFI)" {
	set gfxpayload=keep
	linux	/casper/vmlinuz.efi  file=/cdrom/preseed/ubuntu.seed boot=casper quiet splash --
	initrd	/casper/initrd.lz
}

menuentry "Try Ubuntu 12.04.5 Desktop (EFI)" {
	set gfxpayload=keep
  set isofile=/iso/ubuntu-12.04.5-desktop-amd64.iso
  loopback loop $isofile
  set root=(loop)
  linux (loop)/casper/vmlinuz.efi iso-scan/filename=$isofile file=/cdrom/preseed/ubuntu.seed boot=casper quiet splash locale=en_US.UTF-8 --
  initrd (loop)/casper/initrd.lz
} 

# Install
##########

# - Ubuntu

menuentry "Install Ubuntu 14.04.1 Desktop (EFI)" {
	set gfxpayload=keep
	linux	/casper/vmlinuz.efi  file=/cdrom/preseed/ubuntu.seed boot=casper only-ubiquity quiet splash --
	initrd	/casper/initrd.lz
}

menuentry "Install Ubuntu 14.04.1 Server" {
	set gfxpayload=keep
  set isofile=/iso/ubuntu-14.04.1-server-amd64.iso
  loopback loop $isofile
  set root=(loop)
  linux (loop)/install/vmlinuz iso-scan/filename=$isofile file=/cdrom/preseed/ubuntu-server.seed quiet locale=en_US.UTF-8 --
	initrd (loop)/install/initrd.gz
}

menuentry "Install Ubuntu 12.04.5 Desktop (EFI)" {
	set gfxpayload=keep
  set isofile=/iso/ubuntu-12.04.5-desktop-amd64.iso
  loopback loop $isofile
  set root=(loop)
  linux (loop)/casper/vmlinuz.efi iso-scan/filename=$isofile file=/cdrom/preseed/ubuntu.seed boot=casper only-ubiquity quiet splash locale=en_US.UTF-8 --
  initrd (loop)/casper/initrd.lz
}

menuentry "Install Ubuntu 12.04.5 Server" {
	set gfxpayload=keep
  set isofile=/iso/ubuntu-12.04.5-server-amd64.iso
  loopback loop $isofile
  set root=(loop)
  linux (loop)/install/vmlinuz iso-scan/filename=$isofile file=/cdrom/preseed/ubuntu-server.seed quiet locale=en_US.UTF-8 --
	initrd (loop)/install/initrd.gz
}

# - Debian

menuentry "Install Debian 7.7" {
  set background_color=black
  set isofile=/iso/debian-7.7.0-amd64-CD-1.iso
  loopback loop $isofile
  set root=(loop)
  linux (loop)/install.amd/vmlinuz iso-scan/filename=$isofile vga=788 -- quiet 
  initrd (loop)/install.amd/initrd.gz
} 

# - Other

#menuentry "OEM install (for manufacturers)" {
#	set gfxpayload=keep
#	linux	/casper/vmlinuz.efi  file=/cdrom/preseed/ubuntu.seed boot=casper only-ubiquity quiet splash oem-config/enable=true --
#	initrd	/casper/initrd.lz
#}
#menuentry "Check disc for defects" {
#	set gfxpayload=keep
#	linux	/casper/vmlinuz.efi  boot=casper integrity-check quiet splash --
#	initrd	/casper/initrd.lz
#}

Recovery the grub (If the flash-disk is sdc).

$ sudo mount /dev/sdc /mnt
$ sudo grub-install --root-directory=/mnt/boot /dev/sdc