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

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" <TDaniels@xxxxxxxxxxxxx> wrote in message
news:aJednWYLUNqjuEjeRVn-pA@xxxxxxxxxxxxxx
>
> "Richard Urban" wrote:
>> "Timothy Daniels" wrote:
>>>>> 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!
>>>
>>>
>>> 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.
>
>
> 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*
>


.

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