Ubuntu 10.04 and fedora 14 grub conflict

Question

I tried to triple boot Windows xp, Fedora 14 and Ubuntu 10.04. I first installed Windows xp, then fedora followed by Ubuntu.

The problem is that i don't get option to boot Ubuntu while Xp boots fine. It seems Ubuntu was unable to replace Fedora's grub with its own at MBR. Looking at their grub conf file, Fedora and Ubuntu identifies same harddisk as two different devices and i do have another 80 GB harddisk which doesn't have any OS.

Below is the details on my partitions and partial information from grub files of both OS.

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *          63    40965749    20482843+   7  HPFS/NTFS
/dev/sda2       102414436   312576704   105081134+   f  W95 Ext'd (LBA)
/dev/sda3        40965750   102414374    30724312+  83  Linux - /Home (for fedora)
/dev/sda5       102414438   204812684    51199123+   7  HPFS/NTFS
/dev/sda6       204812748   253634219    24410736   83  Linux -- ubuntu
/dev/sda7       253634283   302455754    24410736   83  Linux -- fedora
/dev/sda8       302455818   312576704     5060443+  82  Linux swap / Solaris

grub.cfg from ubuntu

### BEGIN /etc/grub.d/10_linux ###
menuentry 'Ubuntu, with Linux 2.6.32-21-generic' --class ubuntu --class gnu-linux --class gnu --class os {
    recordfail
    insmod ext2
    set root='(hd1,7)'
    search --no-floppy --fs-uuid --set cd55e078-a2c1-4d8a-9e87-ae838b6f4a05
    linux   /boot/vmlinuz-2.6.32-21-generic root=UUID=cd55e078-a2c1-4d8a-9e87-ae838b6f4a05 ro   quiet splash
    initrd  /boot/initrd.img-2.6.32-21-generic
}
menuentry 'Ubuntu, with Linux 2.6.32-21-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os {
    recordfail
    insmod ext2
    set root='(hd1,7)'
    search --no-floppy --fs-uuid --set cd55e078-a2c1-4d8a-9e87-ae838b6f4a05
    echo    'Loading Linux 2.6.32-21-generic ...'
    linux   /boot/vmlinuz-2.6.32-21-generic root=UUID=cd55e078-a2c1-4d8a-9e87-ae838b6f4a05 ro single 
    echo    'Loading initial ramdisk ...'
    initrd  /boot/initrd.img-2.6.32-21-generic
}
### END /etc/grub.d/10_linux ###

### BEGIN /etc/grub.d/20_memtest86+ ###
menuentry "Memory test (memtest86+)" {
    insmod ext2
    set root='(hd1,7)'
    search --no-floppy --fs-uuid --set cd55e078-a2c1-4d8a-9e87-ae838b6f4a05
    linux16 /boot/memtest86+.bin
}
menuentry "Memory test (memtest86+, serial console 115200)" {
    insmod ext2
    set root='(hd1,7)'
    search --no-floppy --fs-uuid --set cd55e078-a2c1-4d8a-9e87-ae838b6f4a05
    linux16 /boot/memtest86+.bin console=ttyS0,115200n8
}
### END /etc/grub.d/20_memtest86+ ###

### BEGIN /etc/grub.d/30_os-prober ###
menuentry "Microsoft Windows XP Professional (on /dev/sdb1)" {
    insmod ntfs
    set root='(hd1,1)'
    search --no-floppy --fs-uuid --set cad48cc6d48cb5eb
    drivemap -s (hd0) ${root}
    chainloader +1
}
menuentry "Fedora (2.6.35.14-96.fc14.i686) (on /dev/sdb6)" {
    insmod ext2
    set root='(hd1,6)'
    search --no-floppy --fs-uuid --set 6aee34cf-f77a-489a-9361-85d07194b84b
    linux /boot/vmlinuz-2.6.35.14-96.fc14.i686 ro root=UUID=6aee34cf-f77a-489a-9361-85d07194b84b rd_NO_LUKS rd_NO_LVM rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us rhgb quiet
    initrd /boot/initramfs-2.6.35.14-96.fc14.i686.img
}
menuentry "Fedora (2.6.35.6-45.fc14.i686) (on /dev/sdb6)" {
    insmod ext2
    set root='(hd1,6)'
    search --no-floppy --fs-uuid --set 6aee34cf-f77a-489a-9361-85d07194b84b
    linux /boot/vmlinuz-2.6.35.6-45.fc14.i686 ro root=UUID=6aee34cf-f77a-489a-9361-85d07194b84b rd_NO_LUKS rd_NO_LVM rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us rhgb quiet
    initrd /boot/initramfs-2.6.35.6-45.fc14.i686.img
}
### END /etc/grub.d/30_os-prober ### 

grub.conf from fedora

 default=0
timeout=5
splashimage=(hd0,5)/boot/grub/splash.xpm.gz
hiddenmenu
title Fedora (2.6.35.14-96.fc14.i686)
    root (hd0,5)
    kernel /boot/vmlinuz-2.6.35.14-96.fc14.i686 ro root=UUID=6aee34cf-f77a-489a-9361-85d07194b84b rd_NO_LUKS rd_NO_LVM rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us rhgb quiet
    initrd /boot/initramfs-2.6.35.14-96.fc14.i686.img
title Fedora (2.6.35.6-45.fc14.i686)
    root (hd0,5)
    kernel /boot/vmlinuz-2.6.35.6-45.fc14.i686 ro root=UUID=6aee34cf-f77a-489a-9361-85d07194b84b rd_NO_LUKS rd_NO_LVM rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us rhgb quiet
    initrd /boot/initramfs-2.6.35.6-45.fc14.i686.img
title Other
    rootnoverify (hd0,0)
    chainloader +1

Answer 1

Do you have more than one hard drive?

In Grub, (hd1,7) from your Ubuntu grub.conf means the eighth partition of the second hard drive, while (hd0,5) in Fedora's grub.conf means the sixth partition on the first hard drive.

If you are using SCSI drives, your drives' device special files will be /dev/sda*. FireWire, USB, I'm pretty sure Fiber Channel and most RAIDs are considered to be SCSI as well.

The problem with SCSI is that the Linux kernel does not guarantee the drive order in any particular way. I expect your problem is that Ubuntu and Fedora are running different kernels, and that something about those different kernels is changing your drive order.

Your root partitions for both OSes are labeled with GUIDs. I do not know: is it possible to have grub look for the GUIDs instead of the hd0 or hd1?

The hd number is supposed to be the BIOS drive number. If you only had one partition on each drive, then hd0 would be the DOS C: drive while hd1 would be the DOS D: drive, as DOS uses the BIOS to find the drives, rather than going through a kernel and device driver.

If you can figure out why your BIOS drives are in different orders under each OS then I think your problem will be solved. So while I have not answered your question, maybe I have given you some helpful clues.