Sorry for the confusion. To clarify, I meant that usually, only one MBR _is written to_ on a machine. That being the first device the system BIOS recognizes.
In Michael's case (I'm assuming here, but from what he said i believe to be true), "/dev/hda" (AKA MBR of primary master IDE) is setup to passoff to the Linux bootloader. If he installs another IDE drive, be it "/dev/hdb" (primary slave), "/dev/hdc" (secondary master), etc.., and attempts to install Windows XP, the Windows setup will re-write the MBR on the first IDE drive the BIOS sees. (IE: "/dev/hda" (primary master). As I understand, you could go into the BIOS and tell it you don't have a "/dev/hda" (primary master), but would feel safer to just disconnect the drive altogether. That way you know the correct MBR will be written to. Of course there are several other solutions that will work as well, I just thought what I stated in the previous post would be the simpliest, most fool-proof way to make sure you don't toast a MBR. That way the linux bootloader will own the MBR on the primary master, and the Win XP bootloader will own the MBR on the primary slave. Then you only need one drive or the other installed in the system to be able to boot from it. Just modify the boot preferences in the system BIOS. (BTW, at this point, it won't matter which drive is the primary master or slave) Or just install the new IDE drive as the primary master and the Linux drive as the primary slave, and then install Win XP and use the system BIOS to boot between the two.. just remember, if one of the OSes modifies the MBR, it's gonna be the one on the first IDE drive the system BIOS sees. you could also modify lilo.conf to install the bootloader on /dev/hda1 (Partition Boot Record on the primary master), then use dd to make an image of the PBR to a file. then save the file to a floppy. then install Win XP (which will overwrite the MBR on primary master (AKA "/dev/hda") then copy the PBR file to the root of Win XP and add a line to the boot.ini of Win XP so that you could boot either OS. (I know i'm being vague here, but i'd have to lookup exactly what commands/entries would be required.. There is info online to do this however). Or you could do the flip-side and have the Linux bootloader handle booting the two OSes. But in these cases, one of the OSes won't work without both drives being installed. Of course, If I've stated further misconceptions, let us know. I believe this should be somewhat of an accurate generalization of options. On Mon, 26 Aug 2002 17:31:29 -0500 Doc Shipley <[EMAIL PROTECTED]> wrote: > On Mon, 26 Aug 2002, Chris wrote: > > > Important thing to remember is that there is usually only one MBR on a machine. > > If you have a SCSI and IDE mix, it'll setup to the IDE before SCSI > > Um, this is very badly stated. There is one MBR per hard drive. Period. > Some motherboards will automatically boot to IDE-before-SCSI, some > SCSI-before-IDE, but most newer (P-II or better) can be confifured to > your needs. Linux may or may not agree with the BIOS settings after > boottime, which can be really confusing. It's been months since I ran a > mixed system, but IIRC, the kernel considered /dev/hda to be the "first" > drive, not /dev/sda. > > Doc > > _______________________________________________ > Siglinux mailing list > [EMAIL PROTECTED] > http://www.utacm.org/mailman/listinfo/siglinux _______________________________________________ Siglinux mailing list [EMAIL PROTECTED] http://www.utacm.org/mailman/listinfo/siglinux
