I want to share my experience of making my computer to have quad boot using Windows XP, Vista, Ubuntu and Fedora. I have a 160GB HDD which I divided into several partitions. First, I install Windows XP on 30GB partition, and then I install Windows Vista on 100GB partition, followed by Ubuntu 8.04 Hardy on 15GB partition. Finally, I install, Fedora Core 9 on the rest of the space (15GB). First, the system will only boot XP, Vista & Fedora only (triple-booting). In order to boot Ubuntu you need to put the *instruction/command manually in menu.lst in /boot/grub folder (in my case: look at title Ubuntu).

*Remember that the system counts from 0, so if /dev/sda6 (my partition for Ubuntu) is equivalent to (hd0,5).

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Below is the content of the menu.lst in /boot/grub

# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,7)
# kernel /vmlinuz-version ro root=/dev/VolGroup00/LogVol00
# initrd /initrd-version.img
#boot=/dev/sda

default=0
timeout=15
splashimage=(hd0,7)/grub/splash.xpm.gz
hiddenmenu

title Windows XP/Windows Vista
rootnoverify (hd0,0)
chainloader +1

title Fedora
root (hd0,7)
kernel /vmlinuz-2.6.25-14.fc9.i686 ro root=UUID=f488b78c-0b37-48f5-81eb-daae2167e966 rhgb quiet
initrd /initrd-2.6.25-14.fc9.i686.img

title Ubuntu 8.04.1
root (hd0,5)
kernel /boot/vmlinuz-2.6.24-19-generic root=UUID=b65a9665-b277-49dd-bc17-84c076b11d7e ro quiet splash
initrd /boot/initrd.img-2.6.24-19-generic
quiet


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Below is my partition information: ($ fdisk –l)

Disk /dev/sda: 160.0 GB, 160041885696 bytes
255 heads, 63 sectors/track, 19457 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x4fb94fb9

Device Boot Start End Blocks Id System
/dev/sda1 * 1 3824 30716248+ 7 HPFS/NTFS
/dev/sda2 3825 19457 125572072+ f W95 Ext'd (LBA)
/dev/sda5 3825 15377 92799441 7 HPFS/NTFS
/dev/sda6 17290 19361 16643308+ 83 Linux
/dev/sda7 19362 19457 771088+ 82 Linux swap / Solaris
/dev/sda8 15378 15402 200781 83 Linux
/dev/sda9 15403 17289 15157296 8e Linux LVM

Partition table entries are not in disk order

Disk /dev/dm-0: 13.3 GB, 13388218368 bytes
255 heads, 63 sectors/track, 1627 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x00000000

Disk /dev/dm-0 doesn't contain a valid partition table

Disk /dev/dm-1: 2080 MB, 2080374784 bytes
255 heads, 63 sectors/track, 252 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x30307800

Disk /dev/dm-1 doesn't contain a valid partition table

Yep, when you install the OS' in the correct order it does work!

Remember, that the last Linux distro that you install and allow it to install grub to the MBR is always going to be the one that creates the boot menu. If that distro does not automagically detect the other Linux installs, you have to manually add that entry. You can just add the entry from the missing distro's menu.lst, assuming that you installed grub for each distro along the way. I suggest that if you add any more Linux distros, not to keep installing a new grub, but get comfortable with editing your Fedora one. Also, try to keep your partition order the same and not change it. You can add another hard drive to add more distros and add them to the menu. I currently have six distros and Windows in my menu.

Nice work!