Jerry McAllister jerrymc at
Sun Nov 30 14:29:18 PST 2003

> I was hoping that I could partition only the 2d hard drive and install the
> boot manager included on the CD (easy boot I guess) on the 2d hard drive,
> until I read the FAQs online that mentioned this boot manager uses the MBR -
> which must be located on the original, bootable hard drive (I have never
> used a boot manager unless Windows 98 Start-up Menu qualifies).

Just a little clarification here.   Maybe that is all you need to
figure it out.

When the BIOS boots first, before anything on the disk gets going, it
tries to hand control over to boot managers on its list of bootable devices.
Usually nowdays that list is, in order: The floppy drive, the CD, the first
hard drive.   If it doesn't gind anything on the floppy, it goes to the CD,
if it finds nothing there for booting, it goes to the HD.   So, the first
HD has to have something there to accept the handoff from the BIOS.
This is the MBR.

Generally a basic MBR, like the default one in FreeBSD does a couple of
minor things and then looks for bootable slices.
It looks at the boot block of each disk slice on each disk that it
can talk with.   It then gives you a menu and lets you select which
of those slices to boot from.   The default FreeBSD MBR is very functional
but very basic.  It only knows names for a few types of bootable slices.
But, it can set up and hand off controll to any of them that follow
standard boot brocedures - even if it doesn't have a name for it.

When the MBR hands off control, the slice boot record takes over
and continues booting - mainly brings in a kernel to get things
really going.

In FreeBSD this is done with two utilities.   Fdisk not only makes
the slices of a disk, but it also installs the MBR if told to and
it marks slices as bootable or not.

THen disklabel, divides the slices in to partitions and it also
writes the boot record in to the slice if told to do so.

This can all be done from the sysinstall utility during initial
installation because it invokes these utilities when needed with
the needed switches and parameters.  All you have to do is tell
it if the disk needs an MBR and if the slice should be bootable.

Of course, if you have enough of a system running to boot at least to
single user mode and run fdisk and disklabel yourself, you can run
these as you please.  This is especially so when you are setting up
a second disk - possibly as some type of backup or development disk.

Note that some sort of MBR that knows how to boot all the possible 
slice types (eg be able to hand of control to the slice boot block) 
must be on the first disk.    If the WIn-98 MBR can boot the FreeBSD 
slice, then it is fine.  I have heard that Win-98 won't do that.
But, the FreeBSD MBR will boot the Win-98, Win-95, Win-XP, etc slices
just as well as it does a FreeBSD slice.   It just calls the Win-9x
slices MSDOS and the XP unknown or something like that, but it works.


> But then I noticed a reference (link above) to booting from DOS using
> FBSDBOOT.EXE and that got me to wondering if I could just partition ½ of the
> 2d hard drive for FreeBSD, install FreeBSD on that partition and then boot
> to it using the Windows 98 Start-up Menu / DOS. Would FBSDBOOT.EXE find the
> BSD partition on the 2d hard drive? Would I just locate FBSDBOOT.EXE on the
> Windows partition of the 2d hard drive?
> Of course I'm trying to avoid partitioning the orig hard drive w/ WIN98SE,
> and I'd like to use the slave hard drive for both WIN98 backup and FreeBSD.
> Thank you.
> --rs
> ~+
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