How to use BOOT.INI for two primary partitions? First Primary partiton is formatted

  • Thread starter Thread starter David Welch
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David Welch

We start with a computer with two primary partitions. Each of them hold a running WinXP installation.

The BootSelector at startup retrieves the information about ALL, existing, available WinXP systems
ALWAYS from the BOOT.INI file from the first primary partition.

The user can then select from which partiton he wants to boot which WInXP. Fine.

Now lets assume the first primary partition gets corrupted or even accidentially formatted.

The computer boots now. Where does he get the information about the still working WinXP on the
second primary partition when the BOOT.INI on the first primary partition is NOT available any more?

David
 
I see a red herring here. Assuming that the first active partition was
the Active System partition and that the second drive is just a boot
volume containing only the Windows operating system and its support
files, if the first partition is formatted you will not be able to boot
the second installation unless you do a bit of work on the partition(s).

John
 
We start with a computer with two primary partitions. Each of them hold a running WinXP installation.

The BootSelector at startup retrieves the information about ALL, existing, available WinXP systems
ALWAYS from the BOOT.INI file from the first primary partition.

The user can then select from which partiton he wants to boot which WInXP. Fine.

Now lets assume the first primary partition gets corrupted or even accidentially formatted.

The computer boots now. Where does he get the information about the still working WinXP on the
second primary partition when the BOOT.INI on the first primary partition
Click to expand...
is NOT available any more?

1. Boot Selector code is not prerequisite for starting WinXP.
It is an optional extra for users who wish to keep two OSs
available.
2. (Conditional on appropriate BIOS settings) the boot
processs finds and loads WinXP startup code.
3. Is this not what happens in the startup routine you
describe (i.e. the boot routine locates WinXP startup code
on one of your hard drives, and loads it)? If not, repost clarifying
in more detail.your question.
 
David said:
We start with a computer with two primary partitions. Each of them
hold a running WinXP installation.

The BootSelector at startup retrieves the information about ALL,
existing, available WinXP systems ALWAYS from the BOOT.INI file from
the first primary partition.

The user can then select from which partiton he wants to boot which
WInXP. Fine.

Now lets assume the first primary partition gets corrupted or even
accidentially formatted.

The computer boots now. Where does he get the information about the
still working WinXP on the second primary partition when the BOOT.INI
on the first primary partition is NOT available any more?
Click to expand...

Boot.ini on the second drive needs to be modified so that drive #2 becomes
the first drive; ie, as if drive #1 does not exist. for example, if the
boot.ini now looks something like this...

[Boot Loader]
Timeout=5
Default=multi(0)disk(0)rdisk(0)partition(3)\WINDOWS
[Operating Systems]
multi(0)disk(0)rdisk(0)partition(3)\WINDOWS="Windows XP" /noexecute=optin
/fastdetect /noexecute=optout
multi(0)disk(0)rdisk(1)partition(4)\WINDOWS2="XP2 Basic (for emergency)"
/noexecute=optin /fastdetect

It would need to be changed like this...

[Boot Loader]
Timeout=5
Default=multi(0)disk(0)rdisk(0)partition(4)\WINDOWS2
[Operating Systems]
multi(0)disk(0)rdisk(0)partition(4)\WINDOWS2="XP2 Basic (for emergency)"
/noexecute=optin /fastdetect

Note the change in "rdisk".

That entry also needs to be the default. When the boot.ini is like that, the
second drive can be set in BIOS as the first boot device (after floppy and
CD drive if you wish).
_______________________

If you wanted to leave the first drive entry in the boot.ini to allow
booting from it then add...

multi(0)disk(0)rdisk(1)partition(3)\WINDOWS="Windows XP" /noexecute=optin
/fastdetect /noexecute=optout
_________________________

If the BIOS allows more than three boot devices and you have them as floppy,
CD drive, HDD0 then you could just set drive #2 as the boot device after
hard drive #1 (HDD0). Now, if drive #1 goes belly up, you'll boot to drive
#2.

BTW and FWIW, XP need not be on a primary partition.


--

dadiOH
____________________________

dadiOH's dandies v3.06...
....a help file of info about MP3s, recording from
LP/cassette and tips & tricks on this and that.
Get it at http://mysite.verizon.net/xico
 
See below.
David Welch said:
We start with a computer with two primary partitions. Each of them hold
a running WinXP installation.

The BootSelector at startup retrieves the information about ALL, existing,
available WinXP systems
ALWAYS from the BOOT.INI file from the first primary partition.
Click to expand...

*** No. While the boot selector does retrieve information from boot.ini,
this
*** information does not necessarily correspond to existing, available WinXP
*** systems. It's just collection of text lines.
The user can then select from which partiton he wants to boot which WInXP.
Fine.
Click to expand...

*** The user can select any of the menu items that are
*** present in boot.ini. They could refer to existing partitions
*** or they could be totally incorrect.
Now lets assume the first primary partition gets corrupted or even
accidentially formatted.

The computer boots now. Where does he [he?] get the information about the
still working WinXP on the
second primary partition when the BOOT.INI on the first primary partition
is NOT available any more?

David
Click to expand...

*** Here is how the boot process works:
*** 1. The machine executes some code that is located in the
*** Master Boot Record (MBR) of the active partition of the
*** primary master disk.
*** 2. This code will invoke ntldr on that active partition.
*** 3. Ntldr will process boot.ini on that active partition and
*** will present you with a boot selection menu.
*** If the active partition of the primary master disk does not
*** have a suitable MBR then the boot process will fail.
 
Pegasus said:
See below.
David Welch said:
We start with a computer with two primary partitions. Each of them hold
a running WinXP installation.

The BootSelector at startup retrieves the information about ALL, existing,
available WinXP systems
ALWAYS from the BOOT.INI file from the first primary partition.
Click to expand...

*** No. While the boot selector does retrieve information from boot.ini,
this
*** information does not necessarily correspond to existing, available WinXP
*** systems. It's just collection of text lines.
The user can then select from which partiton he wants to boot which WInXP.
Fine.
Click to expand...

*** The user can select any of the menu items that are
*** present in boot.ini. They could refer to existing partitions
*** or they could be totally incorrect.
Now lets assume the first primary partition gets corrupted or even
accidentially formatted.

The computer boots now. Where does he [he?] get the information about the
still working WinXP on the
second primary partition when the BOOT.INI on the first primary partition
is NOT available any more?

David
Click to expand...

*** Here is how the boot process works:
*** 1. The machine executes some code that is located in the
*** Master Boot Record (MBR) of the active partition of the
*** primary master disk.
*** 2. This code will invoke ntldr on that active partition.
*** 3. Ntldr will process boot.ini on that active partition and
*** will present you with a boot selection menu.
*** If the active partition of the primary master disk does not
*** have a suitable MBR then the boot process will fail.
Click to expand...


Slight correction, the MBR does not reside in the active partition or in
any of the partitions, it resides by itself on sector 0 of the hard
drive. The BIOS passes the boot process to the MBR which in turn passes
it to the boot sector of the active partition, the boot sector then
passes it to ntldr.

John
 
David Welch said:
We start with a computer with two primary partitions. Each of them hold a running WinXP installation.

The BootSelector at startup retrieves the information about ALL, existing, available WinXP systems
ALWAYS from the BOOT.INI file from the first primary partition.

The user can then select from which partiton he wants to boot which WInXP. Fine.

Now lets assume the first primary partition gets corrupted or even accidentially formatted.

The computer boots now. Where does he get the information about the still working WinXP on the
second primary partition when the BOOT.INI on the first primary partition is NOT available any more?
Click to expand...

Assuming the second XP install has the necessary boot files, you would need to set the second
primary partition active, and clear the active flag on the first primary. Many third party tools
can do this from a removable media boot.

You may also have to adjust the "new" boot.ini to reflect the new partition order, depending on
the circumstances.
 
David Welch said:
We start with a computer with two primary partitions. Each of them hold
a running WinXP installation.

The BootSelector at startup retrieves the information about ALL, existing,
available WinXP systems ALWAYS from the BOOT.INI file from the
first primary partition.

The user can then select from which partiton he wants to boot which
WInXP. Fine.

Now lets assume the first primary partition gets corrupted or even
accidentially formatted.

The computer boots now. Where does he get the information about the
still working WinXP on the second primary partition when the BOOT.INI
on the first primary partition is NOT available any more?

David
Click to expand...


If the Boot Sector on the "active" Primary partition is corrupted or somehow
unreadable, the bootstrap cannot proceed. If the 2nd Primary partition can
be marked "active" and it has the necessary boot files (i.e. ntldr, boot.ini, and
ntdetect.com) then bootstrapping can proceed provided that the partition table
is not corrupted in the MBR as well. To mark a partition "active" without an
OS running, you'll have to resort to a boot disk to run FDISK. The original
XP installation disk should suffice as a boot disk. (Maybe someone can chime
in at this point.) This is one reason why putting a 2nd OS on a partition on a
differen hard disk is safer - you can always use the BIOS to set which HD
gets control at boot time.

*TimDaniels*
 
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