GRUB question 2253

Pardon my naivete, but is the tilde part of what you added toboot-grub-menu.lst ? Also, if the DOS parbreastion isdev-hda1, why did you write (hd0,1) instead of (hd0,0)? Also, why did you use savedefault and not use rootnoverify?

Another question, a true or false question: TRUE OR FALSE: After writingboot-grub-menu.lst as you have done, does that mean that grub will treat the beginning of the parbreastiondev-hda1 as the boot parbreastion and try to boot from there?

Apart from wanting to know this for its own sake in the present situation, it would be useful to know in case one were inclined to try to create a new operating system and install it on dev-hda1 with its own boot sector program.

I'm planning to download the grub source code and look at it, but it is probably too difficult for me to make sense of what it does at my present stage of competence.

Mon chapeau, Monsieur!

Let me try to understand what you are saying. First, you used Linux to get DOS parbreastiondev-hda1 to be formatted as DOS by using the mkfs.vfat command. Then you used the DOS sys command to transfer the hidden system files from what masquerades as the a: drive to the c: drive.

Now suppose that you did the following: (0) Reformatdev-hda1 with mkfs.vfat to destroy all the good work you've just done. (1) Boot your DOS-CD. (2) Use it to format-s a blank floppy. (3) Remove the CD and the floppy. (4) Reboot to bring up Linux. (5) Put the floppy back into the drive. Question: Can Linux see the hidden system files? (6) In any case, there ought to be a way to know exactly where they sit on the floppy. Use that information with the Linux dd command to copy them to the DOS parbreastiondev-hda1 right after the boot sector i.e. after 512 bytes (or whatever it is).

Now see if your computer will boot the DOS parbreastion.

Thanks. I finally understood what you were talking about in your original posting and was getting ready to try it. But first I have to make a bootable Linux floppy with mkbootdisk and then make sure that grub is installed in it and that I really know how to use grub.

I don't mind installing through the FREEDOS diskette as long as I don't destroy the Linux system in the process. Having to reinstall grub seemed to count as destroying the Linux system, at least a little bit. But it is also a matter of independent interest, from the standpoint of Linux itself, whether one really has to rely on non-Linux tools to install FREEDOS. I'm trying to find out whether the FREEDOS installation software is really shrouded in secrecy. I was under the impression that FREEDOS was completely free software that came with complete source code.

I had another idea, a variant on the one above. Take another machine that is running FREEDOS or DOS. Boot it with a Linux boot floppy. Use dd to copy an incipit of the HD to a file on the boot floppy, maybe 100k or whatever it takes to get the MBR and the hidden system files. Now boot your Linux machine from the HD, insert the floppy and use dd to copy the file on the floppy drive todev-hda1. Then try to boot.

The main thing I can imagine going wrong (not that I really know) is that the MBR of the DOS machine might contain information about the geometry of the HD and parbreastions of that machine, and that might be different from the corresponding information for the Linux machine. But if one knows something about MBR or boot sectors (I don't) then one presumably knows how to edit the file on the floppy before copying it todev-hda1. -- Ignorantly, * Disclaimer: I am a guest and *not* a member of the MIT CSAIL. My actions and * comments do not reflect in any way on MIT. Also, I am nowhere near Boston.