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I am trying to setup windows xp and fc4 on a sony notebook. As I understand, the BIOS looks to the MBR, the MBR knows where to find GRUB, and ...
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    GRUB MBR /boot and 1024-cylinder limit


    I am trying to setup windows xp and fc4 on a sony notebook.

    As I understand, the BIOS looks to the MBR, the MBR knows where to find GRUB, and GRUB will look for /boot. So if this is correct, I let GRUB control the MBR and there should be no worry about the "/boot" partition beyond the 1024-cylinder limit or say at 20 gig since the MBR is most definitly within the limit.

    Thanks for any explainations.

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    Linux User Stefann's Avatar
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    The MBR is ALWAYS at the start of the disk. The /boot partition needs to reside withing the 1024 cylinder limit because the kernel is not actually running until GRUB loads stage 2 and loads the kernel ramdisk, so therefore the BIOS has no access to files above the 1024 cylinder limit until than, so just make a 50MB /boot partition in the front of your disk and you'll be fine.
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    Quote Originally Posted by Stefann
    The MBR is ALWAYS at the start of the disk. The /boot partition needs to reside withing the 1024 cylinder limit because the kernel is not actually running until GRUB loads stage 2 and loads the kernel ramdisk, so therefore the BIOS has no access to files above the 1024 cylinder limit until than, so just make a 50MB /boot partition in the front of your disk and you'll be fine.
    Stefann, thanks for the reply, but just to clarify - I thought that once GRUB was running the BIOS was no loger in control? So, the BIOS and the bootloader are looking for the kernel to load it? Sorry, I am only a biologist.

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    Linux User Stefann's Avatar
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    Quote Originally Posted by tdxloki
    Quote Originally Posted by Stefann
    The MBR is ALWAYS at the start of the disk. The /boot partition needs to reside withing the 1024 cylinder limit because the kernel is not actually running until GRUB loads stage 2 and loads the kernel ramdisk, so therefore the BIOS has no access to files above the 1024 cylinder limit until than, so just make a 50MB /boot partition in the front of your disk and you'll be fine.
    Stefann, thanks for the reply, but just to clarify - I thought that once GRUB was running the BIOS was no loger in control? So, the BIOS and the bootloader are looking for the kernel to load it? Sorry, I am only a biologist.
    The BIOS is no longer in control, but GRUB can only tell the BIOS to boot what it is able to, in other words GRUB can know exactly where the kernel/windoze bootloader is on the disk, but the BIOS isn't able to access them and boot it, to access to anything aboute the 1024 cylinder limit an actual OS(or kernel ramdisk) needs to be loaded.
    Nothing is worse than ten penguins fighting over which is better, vi or emacs.
    Registered Linux User #404402
    Finally I'm back on LF after a long while.

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