Working out Disk device ID's for Windows Boot Loader

[ikonia]

Could someone please explain the method of working out disk id's to go in the boot.ini file for the windows boot loader.

I installed XP and XP 64 on a system, due to a problem with the XP install I had to re-install it, and it didn't pick up the XP 64 install (which sits on a primary sata disk) xp 64 picked up the xp install on the ide disk, but not vice versa.

I'm having problems working out how the disks devices align to the paths in the boot.ini

for example the XP install on my primary ide disk

default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS

how can I work out what my first sata disk would be

I appriciate it will be partition(1) again but how does multi and disk match up to bus and disk.

thanks.

[Paul Adams]

From Windows Internals Fourth Edition:

The multi() syntax follows this format:
multi(W)disk(X)rdisk(Y)partition(Z)

W is the disk controller number (also known as the ordinal number) and is typically 0. X is always 0 in the multi() syntax. Y specifies the physical hard disk attached to the controller W. For ATA controllers, this number is typically between 0 and 3. For SCSI controllers, the number is typically between 0 and 15. Z indicates the partition number on the physical disk that corresponds to the boot volume. The first partition is assigned the number 1.

So I'd guess your SATA controller has a different value for W.

You can add entries to BOOT.INI, so long as the file is valid and the original entries are left intact then you can build a multiboot system with debug, 3G and DEPswitches, for example (even the same partition).

[ikonia]

perfect.

thank you

[ikonia]

despite Pauls clean explination, I find I'm still unable to get my XP 64 installation to boot again.

I'm trying to avoid re-installing XP64 again - but will if I have to, as when I did this the first time, it saw the 32bit install and added it to the boot list for me.

Is there way of actually working out the correct device ID or away of scanning all buses to get the correct options for the boot loader.

I've gone through 0-6 on the multi option, which should work in some way, as Pauls advice suggestets.

I've got 4 channels of 2 IDE buses populated which sould be multi1/2
I've got both the Sata disks populated which should see multi3/4

so as I see it

first sata disk should be

multi(3)disk(0)rdisk(0)partition(1)

or

multi(4)disk(0)rdisk(0)partition(1)

depending on if the sata bus is seen as 1 bus or 2 (1 per disk)

I'm not sure why my install is suggesting that the first partition is partition 1 - I can only assume this is the MS format for partitions.

thanks for the input

[Paul Adams]

I would be tempted to boot off the x64 XP CD/DVD and try a repair option, after backing up my current BOOT.INI - possibly need to F6 to load the SATA drivers, mind...

[ikonia]

good advice.

I'll do this tonight.

[TheAnimus]

erm, forgive my plain ignorance, as i've never used IDE on my dual booting systems, but wouldn't multi be a max of 1, 0 for primary IDE, 1 for secondary IDE.

my SCSI was always 2. or 1 (i think it was one when i disabled the IDE channel that wasn't in use by the cd drive).

[ikonia]

I'm trying to boot from sata which is treated as SCSI from what I've read, hence the 3 or 4 id.

I'll see what the repair options shows as Paul suggested.

[TheAnimus]

okay, one more time to try n explain.

0, primary IDE
1, secondary IDE
2, ???
3, ATA ?

surely it would be two not 3?

[TheAnimus]

just done some checking, multi is determined by your boot order BIOS:

Theoretically, this syntax could be used to start Windows NT on any drive in the system. However, this would require that all drives are correctly identified through the standard INT 13 interface; since support for this varies from disk controller to disk controller and most system BIOS only identify a single disk controller through INT 13, in practice it is only safe to use this syntax to start Windows NT from the first two drives connected to the primary disk controller, or the first four drives in the case of a dual-channel EIDE controller.

you could try the SCSI sytnax, as if you've got an addin card BIOS for the SATA it might not work enless a driver is specifically loaded (this is what SCSI makes it do!)