mirror of
https://github.com/freebsd/freebsd-src.git
synced 2024-12-03 08:22:44 +00:00
93 lines
4.7 KiB
Plaintext
93 lines
4.7 KiB
Plaintext
Boot Manager Selection:
|
|
-----------------------
|
|
|
|
If you wish to switch between multiple operating systems on your
|
|
machine, or if you are trying to install FreeBSD on a drive other than
|
|
your 1st drive, then you must install a boot manager. In the case
|
|
where you wish to boot off an alternate drive, it should also be noted
|
|
that you still need to install a boot manager on the FIRST drive!
|
|
Even if you do not intend to create a FreeBSD partition on that drive
|
|
(e.g. it's being wholly used by something else), the boot manager
|
|
still needs to reside on the first disk in order to function as a
|
|
"redirector" for the boot process.
|
|
|
|
To do this, simply select your 1st drive in the drive selection menu
|
|
and when the partition editor comes up, don't make any changes - just
|
|
(Q)uit. At the boot manager menu which follows, select the first
|
|
option (install a boot manager) and then proceed to setup the other
|
|
drive(s) for FreeBSD as normal.
|
|
|
|
It should also be noted that "operating systems" such as Windows 95
|
|
will completely overwrite your boot manager without so much as a
|
|
polite "may I please destroy your boot manager?" prompt if you make
|
|
the mistake of installing them second. If this happens to you after
|
|
FreeBSD is already installed, all is not lost! Simply revisit your
|
|
FreeBSD distribution directory and look for a tools/ subdirectory, in
|
|
which you'll find "bootinst.exe" and "boot.bin". To reinstall, simply
|
|
say "bootinst boot.bin" while in the tools/ subdirectory.
|
|
|
|
|
|
If you see the boot manager displaying ``F?'' when you try to come up
|
|
for the first time and it refuses to change, no matter how often you
|
|
whap on the function key assigned to FreeBSD, then you have a geometry
|
|
mismatch problem and you should read the next section for important
|
|
information on how to prevent that exact problem from happening!
|
|
|
|
|
|
Geometry Translation / Sharing the disk(s) with another OS:
|
|
----------------------------------------------------------
|
|
|
|
If you are going to actually install some portion of FreeBSD on a
|
|
drive then PLEASE BE VERY CERTAIN that the Geometry reported in the
|
|
Partition Editor is the correct one for your drive and controller
|
|
combination!
|
|
|
|
IDE drives often have a certain geometry set during the PC BIOS setup,
|
|
or (in the case of larger IDE drives) have their geometry "translated"
|
|
by either the IDE controller or a special boot-sector translation
|
|
utility such as that by OnTrack Systems. In these cases, knowing the
|
|
correct geometry gets even more complicated as it's not something you
|
|
can easily tell by looking at the drive or the PC BIOS setup. The
|
|
best way of verifying that your geometry is being correctly calculated
|
|
in such situations is to boot DOS (from the hard disk, not a floppy!)
|
|
and run the ``pfdisk'' utility provided in the tools/ subdirectory of
|
|
the FreeBSD CDROM or FTP site. It will report the geometry that DOS
|
|
sees, which is generally the correct one.
|
|
|
|
If you have no DOS partition sharing the disk at all, then you may
|
|
find that you have better luck with Geometry detection if you create a
|
|
very small DOS partition first, before installing FreeBSD. Once
|
|
FreeBSD is installed you can always delete it again if you need the
|
|
space.
|
|
|
|
It's actually not a bad idea (believe it or not) to have a small
|
|
bootable DOS partition on your FreeBSD machine anyway: Should the
|
|
machine become unstable or exhibit strange behavior at some point in
|
|
the future (which is not uncommon behavior for PC hardware!) you can
|
|
then at least use DOS for installing and running one of the
|
|
commercially available system diagnostic utilities.
|
|
|
|
IMPORTANT NOTE:
|
|
|
|
Any root partition you try to boot from must also reside below the
|
|
1024th cylinder. If you're using a translated geometry then this is
|
|
probably not a problem, but if you are using a native disk geometry
|
|
which exceeds 1024 cylinders then you could have a failure to boot if
|
|
you end up installing a root partition (or even just the kernel file
|
|
in a root partition) out past cylinder 1024. If you are trying to
|
|
share your first disk with FreeBSD and another OS which was installed
|
|
previously, you are particularly susceptible to this problem and should
|
|
check your disk addresses very carefully.
|
|
|
|
If you find that you have insufficient space below cylinder 1024 to
|
|
make a root partition for FreeBSD (and again, this ONLY applies to the
|
|
root partition - once FreeBSD's kernel is loaded, it doesn't care
|
|
about the geometry issues) then you will probably need to install on a
|
|
completely different disk (see the boot manager section above) or
|
|
resize your existing partitions so that both operating systems can
|
|
have boot partitions below cylinder 1024.
|
|
|
|
You may blame IBM for the limitations of a 10 bit cylinder address.
|
|
"No one will have a disk with more than 1024 cylinders." I'm sure
|
|
someone said.
|