Re: Dual Boot / Alternate Boot Questions

"Gary Brown" wrote:
I will install a second copy of XP on a separate hard disk.
It would run either as a dual boot or with either disk
disconnected. Normally, it would be dual boot. But in case
of disk failure the alternate installation will boot. Is this possible?
Will there be problem getting either OS to boot as "C:"?

I have run triple boot in the past (98/NT4/2003 in separate
partitions) but all on the same disk.

Thanks,
Gary

Piece of cake with Microsoft's own boot.ini boot menu.
There really is no reason to have either OS call its own
partition "C:" as long as each has no shortcuts that point
to other partitions. But if that's what you want, just install
each OS separately to its own hard disk (i.e. with the other
hard disk disconnected). If there are no other OSes on the
disk, the installer will tell the installed OS that its partition is
to be called "C:" - and that's what it will do.

Then, in each OS, add a second boot option to the boot
menu file, which is /boot.ini . (You may have to allow System
files to be unhidden in order to see boot.ini by clicking Show
Hidden Files and Folders in Tools/Folder Options/View tab.)
There will be an entry line under "[operating systems]" that has
rdisk() and partition() components. In rdisk(x), the argument
"x" stands for the boot priority of the hard disk - "0" being the
highest priority, and values range up to "3". In some BIOSes,
the user can set the boot priority of all the hard disks in the system
in arbitray order. In other BIOSes, you "enable" one hard disk
as having the highest priority. In partition(y), "y" stands for the
no. of the partition that contains the OS, starting with "1".
Partitions are numbered starting with the Primary partitions,
and then going to the logical drives in the Extended partition.
(Yes, you can boot an OS that resides on a logical drive in an
Extended partition.) The installer should set the Primary
partition that contains the boot files (ntldr, boot.ini, and
NTdetect.com) to "active". Normally, that partition is the
same as that which contains the OS, but it doesn't have to be.
It wouldn't hurt to use Disk Management to check that the
partition is, indeed, set to "active". If not, set it so.

Since each OS had been installed on a sole hard disk, its
boot.ini file will have "rdisk(0)" in its operating system entry
line. If you had installed each OS in the 1st partition of its hard
disk, both boot.ini files will have "partition(1)" in the entry line.
To make each OS offer the other OS as a boot option in the
boot menu, just add a 2nd line under "[operating systems]"
that has "rdisk(1)" instead of "rdisk(0)". Then at boot time,
regardless which hard disk has boot priority, you can always
select the OS on the local hard disk or the other hard disk.
If one hard disk's MBR gets corrupted, the other hard disk
will be selected (theoretically), and its OS will be booted
automatically because its OS will be the OS indicated in the
"default=" line.

Then you will have several ways to dual-boot. You can
set the boot priority in the BIOS, or you can choose the OS
from the boot menu, or you can swap hard disks. Simple,
yes? And it's all done with Microsoft's own boot software.

BTW, thanks for spelling "separate" correctly. Many
posters spell it "seperate".

*TimDaniels*





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