How to have triple boot Linux Mint 17 Cinnamon/Ubuntu 14.04/Windows 8?

Question

I have installed Ubuntu 14.04 and Windows 8 as a dual boot system, now I want to install Linux Mint 17 and have a triple boot system. How can I have Mint 17 in my triple booting? How can I partitioning my HDD? I want to install that with USB and not using windows installer.

Answer 1

Just install normally. You can boot from your USB and follow the steps of the installer. You can either create a partition manually before installing or use the tools provided by the Mint installer to partition during the installation process.

The only thing you really have to worry about is when the installer asks you whether to install a boot loader (GRUB). Then, you have 2 choices. Since you already have a GRUB installed by Ubuntu, you can either choose to not install a new one from mint and use Ubuntu's or you can install Mint's and overwrite Ubuntu's.

1. Use the existing GRUB.

   When the installer asks you whether to install a boot loader, say no. Once the installation has finished, reboot and load Ubuntu (Mint will not appear in the list of available OSs). From Ubuntu, refresh GRUB so it will detect your new Mint installation:

   sudo update-grub
   

2. Use Mint's GRUB.

   When the installer asks you whether to install a boot loader, say yes. Make sure you install it in the same location where your Ubuntu's GRUB was installed. This will probably be the master boot record (MBR) of your primary hard drive. Reboot and you should now have Mint's GRUB installed and will be able to choose Mint, Ubuntu or Windows.

Answer 2

Most systems support booting different installations from different partitions. I have found multiboot with multiple Linux installations to work best, if each install has its own copy of GRUB.

Loading GRUB from within GRUB is quite simple if you are using a recent version of GRUB.

This /etc/grub.d/40_custom file allows me to multiboot between different versions of Ubuntu. It should look similar on other distributions, though the configuration file might have a different name, and obviously the path to core.img will be different in each case.

#!/bin/sh
exec tail -n +3 $0
# 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.

set timeout=25
set timeout_style=menu

menuentry 'Raring' { multiboot /raring/boot/grub/i386-pc/core.img }
menuentry 'Saucy' { multiboot /saucy/boot/grub/i386-pc/core.img }
menuentry 'Trusty' { multiboot /trusty/boot/grub/i386-pc/core.img }

Booting multiple Linux distributions from a single partition is possible. I don't know any distribution supporting this out-of-the-box, but most distributions can do it with minor changes. I have been using this /usr/share/initramfs-tools/hooks/rootdir file to boot Ubuntu and Debian from a subdirectory rather than from the root of a partition:

#!/bin/sh
# /usr/share/initramfs-tools/hooks/rootdir

set -e

if [ "$1" = prereqs ]; then
    exit 0
fi

. /usr/share/initramfs-tools/hook-functions

DEFAULT_DIR="$(/usr/bin/grub-mkrelpath /)"

mkdir -p "$DESTDIR"/scripts/local-bottom
cat >"$DESTDIR"/scripts/local-bottom/rootdir <<EOF
#!/bin/sh

PREREQ=""
prereqs()
{
     echo "\$PREREQ"
}

case \$1 in
prereqs)
     prereqs
     exit 0
     ;;
esac

ROOTDIR="$DEFAULT_DIR"

for x in \$(cat /proc/cmdline); do
    case \${x} in
    rootdir=*)
        ROOTDIR="\${x#rootdir=}"
        ;;
    esac
done

if [ -n "\${ROOTDIR#/}" ] && [ -d "/root/\${ROOTDIR}" ]
then
    [ -d /rootfs ] || mkdir -m 0700 /rootfs
    mount --move "/root" "/rootfs"
    mount --bind "/rootfs/\${ROOTDIR}" "/root"
    umount "/rootfs"
fi

EOF

chmod 0755 "$DESTDIR"/scripts/local-bottom/rootdir