A Dual-boot question; I thought C was always the partition with the running OS

[Al Dykes]

I've never screwed with booting Windows from more than one disk or
partition, before, but I was under the impression that C: would be
pointed to whatever partition had the running system.

Now I'm playing with a system that has two disks. They show up as C
and E. C has XP, E has server 2003. Boot.ini has entries for both but
when I puck the second, HOMEDRIVE is E. Which is right, but breaking
lots of setup scripts. Grrr.

Am I immagining the boot-partition-is-always-called-C thing?

Thanks

 

[Pegasus \(MVP\)]

I've never screwed with booting Windows from more than one disk or
partition, before, but I was under the impression that C: would be
pointed to whatever partition had the running system.

Now I'm playing with a system that has two disks. They show up as C
and E. C has XP, E has server 2003. Boot.ini has entries for both but
when I puck the second, HOMEDRIVE is E. Which is right, but breaking
lots of setup scripts. Grrr.

Am I immagining the boot-partition-is-always-called-C thing?

Thanks

C: is the default drive letter for the boot partition but it
can be anything. It is even possible to have a system
that uses a drive letter other than C:, even though the
boot partition is the very first partition on the primary
master disk . . .

Those who are serious about multi-booting machines
will use a third party boot manager such as XOSL.
It lets them run each OS in its own partition, completely
independent from any other OS, with each boot partition
being visible as drive C:. Your method has a number of
dependencies and it causes the drive letter problem that
is the source of your irritation.

 

[Richard Urban]

The operating system runs from the partition that you install it upon. The
dual boot capabilities are rather rudimentary and don't offer you many
choices.

Buy a third party boot manager program to do what you want. I use System
Commander. Any operating system I boot into is seen as Drive/Partition C: -
no matter where I physically have them installed to.

--


Regards,

Richard Urban
Microsoft MVP Windows Shell/User

Quote from George Ankner:
If you knew as much as you think you know,
You would realize that you don't know what you thought you knew!

 

[Timothy Daniels]

I've never screwed with booting Windows from more
than one disk or partition, before, but I was under the
impression that C: would be pointed to whatever
partition had the running system.

Now I'm playing with a system that has two disks.
They show up as C and E. C has XP, E has server 2003.
Boot.ini has entries for both but when I puck the second,
HOMEDRIVE is E. Which is right, but breaking lots of
setup scripts. Grrr.

Am I immagining the boot-partition-is-always-called-C thing?

Have you tried this: Install the Server 2003 on a separate
hard drive withOUT the WinXP hard drive connected. The
Server 2003 will then call its partion "C:" Local Disk. Then
modify the WinXP single-boot boot.ini file so that it will
dual-boot. (Since it's already dual-booting, you can leave
boot.ini as it is now.) When WinXP starts up, it will see the
Server 2003 partition as "E:", but who cares? When
Server 2003 starts up, it will call itself "C:" and it will call the
WinXP partition "E:", but again, who cares? This will be
a situation analogous to dual-booting between different
clones of the same OS. Each will call itself "C:" and the
other clone some other letter, but who cares?

*TimDaniels*

 

[Pegasus \(MVP\)]

Have you tried this: Install the Server 2003 on a separate
hard drive withOUT the WinXP hard drive connected. The
Server 2003 will then call its partion "C:" Local Disk. Then
modify the WinXP single-boot boot.ini file so that it will
dual-boot. (Since it's already dual-booting, you can leave
boot.ini as it is now.) When WinXP starts up, it will see the
Server 2003 partition as "E:", but who cares? When
Server 2003 starts up, it will call itself "C:" and it will call the
WinXP partition "E:", but again, who cares? This will be
a situation analogous to dual-booting between different
clones of the same OS. Each will call itself "C:" and the
other clone some other letter, but who cares?

*TimDaniels*

Could you explain why the server installation would appear
as drive C: while both disks are connected? Have you tried
this for yourself? Just because Windows Server was installed
on drive C: does NOT mean that it will stick to this letter
with both disks connected!

 

[Timothy Daniels]

Could you explain why the server installation would appear
as drive C: while both disks are connected? Have you tried
this for yourself? Just because Windows Server was installed
on drive C: does NOT mean that it will stick to this letter
with both disks connected!

I have not tried this myself. But why would it not work?
If an OS is installed on an isolated hard drive, it will call its
partition the "C:" Local Disk, just as the OP's WinXP OS
has done. If the Server 2003 is installed on an isolated hard
drive, I have assumed that it will call its partition the "C:"
Local Disk as well. Then the situation will be analogous
to having an OS running with its clone visible - the running
OS calls its partition "C:" and it refers to the partition
containing the other OS by some other name, such as "E:".
And when the 2nd OS is running, it also calls its partition
the "C:" Local Disk, and it calls the 1st OS's partition
some other name, such as "E:". This is what clones do,
so why wouldn't two OSes which have been installed in
isolation from each other do the same? Please realize
that I'm saying that the RUNNING operating system will call
its partition "C:", while the other OS is merely seen as a
file hierarchy in another partition. I am NOT saying that
an OS that is NOT running will have its partition known as
"C:" by the running OS.

*TimDaniels*

 

[Pegasus \(MVP\)]

I have not tried this myself. But why would it not work?
If an OS is installed on an isolated hard drive, it will call its
partition the "C:" Local Disk, just as the OP's WinXP OS
has done. If the Server 2003 is installed on an isolated hard
drive, I have assumed that it will call its partition the "C:"
Local Disk as well. Then the situation will be analogous
to having an OS running with its clone visible - the running
OS calls its partition "C:" and it refers to the partition
containing the other OS by some other name, such as "E:".
And when the 2nd OS is running, it also calls its partition
the "C:" Local Disk, and it calls the 1st OS's partition
some other name, such as "E:". This is what clones do,
so why wouldn't two OSes which have been installed in
isolation from each other do the same? Please realize
that I'm saying that the RUNNING operating system will call
its partition "C:", while the other OS is merely seen as a
file hierarchy in another partition. I am NOT saying that
an OS that is NOT running will have its partition known as
"C:" by the running OS.

*TimDaniels*

This is not the way it works. If you have two OSs on a disk
and if the drive letter for the first one is C: then the drive
letter for the second OS won't be C:, regardless of what
letter was used at install time - unless you hide the first
partition! I note that you said nothing about hiding partitions.

I recommend you try this for yourself rather than taking
my word for it.

 

[Richard Urban]

I have not tried this myself. But why would it not work?
If an OS is installed on an isolated hard drive, it will call its
partition the "C:" Local Disk, just as the OP's WinXP OS
has done. If the Server 2003 is installed on an isolated hard
drive, I have assumed that it will call its partition the "C:"
Local Disk as well. Then the situation will be analogous
to having an OS running with its clone visible - the running
OS calls its partition "C:" and it refers to the partition
containing the other OS by some other name, such as "E:".
And when the 2nd OS is running, it also calls its partition
the "C:" Local Disk, and it calls the 1st OS's partition
some other name, such as "E:". This is what clones do,
so why wouldn't two OSes which have been installed in
isolation from each other do the same? Please realize
that I'm saying that the RUNNING operating system will call
its partition "C:", while the other OS is merely seen as a
file hierarchy in another partition. I am NOT saying that
an OS that is NOT running will have its partition known as
"C:" by the running OS.

*TimDaniels*

From Partition Magic 7.01 Manual:



How the OS Assigns Drive Letters

DOS, Windows 3.x, Windows 95/98/Me, and OS/2

These OSs assign drive letters in a fixed sequence which cannot be changed.
This

sequence is as follows:

• The OS begins by assigning a drive letter to the first primary partition
that it

recognizes on the first system hard disk. The OS then assigns drive letters
to the first

primary partition recognized on each successive hard disk. For example,
imagine you

have three hard disks in your system. When you boot your OS, it assigns
drive letter

C: to the active primary partition on the first hard disk. Drive letter D:
is assigned to

the first primary partition that the OS recognizes on the second hard disk,
and drive

letter E: is likewise assigned to the first primary partition on the third
disk.

If you have multiple visible primary partitions on a single hard disk, the
OS assigns

the drive letter to the active partition. If none of the partitions are
active, the drive

letter is assigned to the first visible primary partition recognized by the
OS.

WARNING! Making multiple primary partitions visible on the same drive can
cause

data loss in DOS, Windows 3.x, Windows 95/98/Me and OS/2.

• Next, all logical partitions recognized by the OS are assigned drive
letters, starting

with the logical partitions on the first hard disk and proceeding in order.
For example,

suppose you have two hard disks in your system, each with one primary and
two

logical partitions. The OS first assigns C: and D: to the two primary
partitions, then

assigns drive letters E: and F: to the first and second logical partitions
on the first hard

disk. Drive letters G: and H: are assigned to the two logical partitions on
the second

disk.

• The OS then assigns drive letters to any remaining visible primary
partitions, starting

with those on the first hard disk. The OS proceeds to any visible primary
partitions on

the second disk, then the third disk, and so on.

• Finally, CD-ROM drives and other types of removable media are assigned a
drive

letter.

Because the OS always follows this sequence to assign drive letters, adding
or removing a

second hard disk can cause changes to your drive letter assignments.
Likewise, drive

letters can change if you add, remove, or copy a disk partition; reformat a
partition with a

different file system; or boot a different OS.


--


Regards,

Richard Urban
Microsoft MVP Windows Shell/User

Quote from George Ankner:
If you knew as much as you think you know,
You would realize that you don't know what you thought you knew!

 

[Timothy Daniels]

This is not the way it works. If you have two OSs on a disk
and if the drive letter for the first one is C: then the drive
letter for the second OS won't be C:, regardless of what
letter was used at install time - unless you hide the first
partition! I note that you said nothing about hiding partitions.

I recommend you try this for yourself rather than taking
my word for it.

Please read the thread above. Here is what the
original poster wrote:
"Now I'm playing with a system that has two disks.
They show up as C and E. C has XP, E has
server 2003."

Here is what I replied:
"Have you tried this: Install the Server 2003 on a separate
hard drive withOUT the WinXP hard drive connected."

Obviously, the Server 2003 installer would NOT see the
WinXP's partition during the installation procedure for
Server 2003.

*TimDaniels*

 

[Timothy Daniels]

From Partition Magic 7.01 Manual:

How the OS Assigns Drive Letters

DOS, Windows 3.x, Windows 95/98/Me, and OS/2

These OSs assign drive letters in a fixed sequence
which cannot be changed.

This sequence is as follows:

• The OS begins by assigning a drive letter to the
first primary partition that it recognizes on the
first system hard disk. The OS then assigns
drive letters to the first primary partition recognized
on each successive hard disk.
For example,
imagine you have three hard disks in your system.
When you boot your OS, it assigns drive letter C:
to the active primary partition on the first hard disk.
Drive letter D: is assigned to the first primary
partition that the OS recognizes on the second hard
disk, and drive letter E: is likewise assigned to the
first primary partition on the third disk.
If you have multiple visible primary partitions on a
single hard disk, the OS assigns the drive letter
to the active partition. If none of the partitions are active, the drive letter is assigned to the first visible
primary partition recognized by the OS.

WARNING! Making multiple primary partitions visible
on the same drive can cause data loss in DOS,
Windows 3.x, Windows 95/98/Me and OS/2.

• Next, all logical partitions recognized by the OS
are assigned drive letters, starting with the logical
partitions on the first hard disk and proceeding in
order.
For example,
suppose you have two hard disks in your system,
each with one primary and two logical partitions.
The OS first assigns C: and D: to the two primary partitions, then assigns drive letters E: and F: to
the first and second logical partitions on the first
hard disk. Drive letters G: and H: are assigned to
the two logical partitions on the second disk.

• The OS then assigns drive letters to any remaining
visible primary partitions, starting with those on the
first hard disk. The OS proceeds to any visible primary partitions on the second disk, then the third disk,
and so on.

• Finally, CD-ROM drives and other types of removable
media are assigned a drive letter. Because the OS
always follows this sequence to assign drive letters,
adding or removing a second hard disk can cause
changes to your drive letter assignments. Likewise, drive letters can change if you add, remove,
or copy a disk partition; reformat a partition with a
different file system; or boot a different OS.

Do you guys read what even you yourselves write, much
less what other posters, such as myself, write?

1) The above treatise is about what a running OS calls
its own partition and the other partitions that it sees.
When the OP's WinXP and Server 2003 are installed,
all that they will see is their own partitions. Why?
Because they're on separate hard drives, and I
suggested that the OP re-install the Server 2003 with
the WinXP-containing hard drive dis-connected.
Each OS, when it is RUNNING, will therefore refer
to its own partition as "C:", just as clones do, and
it will rename the other partitions as it sees fit, also
just as clones do.

2) The above treatise pertains to what is says are
"DOS, Windows 3.x, Windows 95/98/Me, and OS/2".
If you think this will also apply to WinXP and Server
2003, at least SAY so.

*TimDaniels*

 

[Richard Urban]

The information holds true for any operating system since DOS. You can not
do as you said. You can not have two window installs on two different drives
(both active and visible) and have them both seen as drive C: when you boot
up either one. The one that is NOT being booted must be hidden from the one
that is being booted. Third party boot managers do just that.

Suggest you try what you preach. I have, and it doesn't work. If it did
there would not be any need for third party boot managers.

--


Regards,

Richard Urban
Microsoft MVP Windows Shell/User

Quote from George Ankner:
If you knew as much as you think you know,
You would realize that you don't know what you thought you knew!

 

[Timothy Daniels]

"Timothy Daniels"wrote:

The information holds true for any operating system
since DOS. You can not do as you said. You can not
have two window installs on two different drives (both active and visible) and have them both seen as
drive C: when you boot up either one. The one that
is NOT being booted must be hidden from the one that is being booted. Third party boot managers do
just that.

Suggest you try what you preach. I have, and it doesn't
work. If it did there would not be any need for third party
boot managers.

Richard Urban
Microsoft MVP Windows Shell/User

Here is what you wrote (above):
"You can not have two window installs on two
different drives (both active and visible) and
have them both seen as drive C: when you
boot up either one."

Here is what I have been saying:
"You can have two window installs on two
different drives that were isolated from each
other during the installation processes and
have each of them, when run with the other OS's
partition visible, refer to its own partition as "C:"
and refer to the partition of the non-running OS
as some other name/letter." Obviously, both
hard drives are NOT to be "active and visible"
during the installation of an OS on each of them.

Here is my rationale: A clone of an OS is the
same as another installation of the OS done in
isolation from the 1st installation. This is because
the 2nd installation is a duplication of the 1st
installation - when the OS cquld not see its clone
because the clone did not exist, yet. To verify this,
each, when run alone (i.e. without the other OS's
partition visible) will refer to its own partition as "C:".
Each, when run with the other OS's partition visible,
will call its own partition "C:" and the other OS's
partition "D:" or "E:" or "F:", etc. Note that the most
practical way to make the other OS's partition
invisible during the installation process is to have
the two partitions on separate hard drives and to
temporarily disconnect the hard drive not undergoing
the OS installation.

I suspect that you are not disconnecting the 1st hard
drive when installing the OS on the 2nd hard drive.

As for 3rd party boot managers, the WinXP boot
manager should work in this situation since the OP
has seen it work. The only thing necessary is to
manually add the 2nd entry to boot.ini files of the
partition which is to do the booting. Normally, this
is done automatically during a dual-boot installation
because the installer can see the extant OS and it
will create an entry in boot.ini for it. But when the
installations are done separately, as I have here
been suggesting, the boot.ini file will be created with
the assumption of single-booting. If the OP will be
satisfied with adjusting the BIOS's hard drive boot
order to select which OS boots rather than using
the boot manager's dual-boot function, no adjustment
to the boot.ini of either partition would be necessary.

*TimDaniels*

 

[Richard Urban]

And again - YOU have done this, or are you just surmising that it is so? I
have tried it. It does not work. When once you connect both drives and boot
to each system in sequence, you will see what I mean.

--


Regards,

Richard Urban
Microsoft MVP Windows Shell/User

Quote from George Ankner:
If you knew as much as you think you know,
You would realize that you don't know what you thought you knew!

 

[Timothy Daniels]

Al Dykes:

Since you have an installation CD for Server 2003
and you have the motivation to see your dual-boot
installation work so that each OS, when running, will
call its own partition "C:", just do this, if only for edification:

1) Dis-connect the hard drive with the WinXP OS.
2) Then install Server 2003 on the 2nd hard drive
from scratch.
3) Shut down the computer.
4) Then re-connect the WinXP-containing hard drive
so that both hard drives are connected.
5) Start the computer.
6) Set the BIOS's hard drive boot order so that the
WinXP-containing hard drive is at the top of the list.
7) Re-start the computer. WinXP shoud boot up,
calling its own partition "C:" and the Server 2003
partition something else, such as "D:" or "E:".
8) Re-start the computer.
9) Set the BIOS's hard drive boot order so that the
Server 2003-containing hard drive is at the top
of the list.
10) Re-start the computer. Server 2003 should boot up,
calling its own partition "C:" and the WinXP
partition something else, such as "D:" or "E:"
11) If you want to create a dual-boot capability, add
a 2nd entry to the boot.ini file of the partition that
you want to be the boot manager. This hard drive
should be put at the head of the BIOS's hard drive
boot order. The only difference between the 1st
entry and the 2nd entry (in this situation) is that the
2nd entry will have the argument "rdisk(1)" instead
of "rdisk(0)". Also, to give yourself enough time to
decide between the two options during bootup,
set the TIMEOUT value to 10 to signify 10 seconds.
If you would like EITHER partition to be the boot
manager, alter the boot.ini files of both partitions
in the same way. Each will think of its own hard
drive as "rdisk(0)" and the other hard drive as
"rdisk(1)", and it won't matter which hard drive is
at the head of the boot order. Set the character
strings between the quotes to be anything that makes
sense to you. Obviously, the positions of the strings
"Windows XP" and "Server 2003" would be reversed
in the two boot.ini files.

*TimDaniels*

 

[Timothy Daniels]

And again - YOU have done this, or are you just surmising
that it is so? I have tried it. It does not work. When once
you connect both drives and boot to each system in
sequence, you will see what I mean.

I have said that I have not tried this, the reason being
that I don't have a copy of a Server 2003 installation CD.
But why be so coy? Just TELL us what you did and what
you observed.

*TimDaniels*

 

[Pegasus \(MVP\)]

I have said that I have not tried this, the reason being
that I don't have a copy of a Server 2003 installation CD.
But why be so coy? Just TELL us what you did and what
you observed.

*TimDaniels*

You don't need a copy of Windows 2003 server - just
install a second copy of WinXP, following your own recipe,
and see what happens.

As other respondents have said: It is fine to propose a
theory but to validate it you ***must*** test it in practice.
So far it's been lots of word from you and no action
whatsoever. I'm happy to continue this thread ***after***
you have reported your experimental results in detail.

 

[Richard Urban]

For someone who is only surmising, you sure do argue a lot.

When you install each operating system (I don't really care if it is Win2000
or winXP or whatever) on it's own primary partition on it's own hard drive,
connected as a single and only drive in the computer, each system will be on
Drive/partition/volume C:

When you connect up the two drives, and boot the system on the master drive,
the system on the master hard drive will be seen as Drive C:, the system on
the slave drive will be seen as D:.

When you boot up the O/S on the slave drive, the system will be seen as
drive D:, but will be accessing many files that are on drive C: (the other
operating system) BECAUSE that is where the registry entries of the system
on the slave drive point to. Can you guess why?

You will have a totally f***ed up system, using half of one drive and half
of the second drive.

This is just the way it is. You can not change it after the fact! You can
not prevent it from happening without hiding the system you are NOT booted
into.

Now, please go and download some reading material, the likes of which I
already posted (which you take exception to because you know better) and
learn.

--


Regards,

Richard Urban
Microsoft MVP Windows Shell/User

Quote from George Ankner:
If you knew as much as you think you know,
You would realize that you don't know what you thought you knew!

 

[Richard Urban]

I apologize for my outburst, but you are so frustrating.

--


Regards,

Richard Urban
Microsoft MVP Windows Shell/User

Quote from George Ankner:
If you knew as much as you think you know,
You would realize that you don't know what you thought you knew!

 

[Pegasus \(MVP\)]

No need to apologize. Have you ever tried to reason with
the inventor of a perpetual motion device? They keep
arguing about it, they take out patents if they can, they
take people's money but they never ever deliver anything,
because they can't.

 

[Timothy Daniels]

As other respondents have said: It is fine to propose a
theory but to validate it you ***must*** test it in practice.
So far it's been lots of word from you and no action
whatsoever. I'm happy to continue this thread ***after***
you have reported your experimental results in detail.

How about you reporting your experimental procedure
and results as well so that we may test it? So far, you guys
have just SAID that you "tried it" with negative results. Well,
HOW did you try it, and WHAT results did you get?

*TimDaniels*