Is boot.ini the only reference to partition number in XP?

[torandson]

HI,
I have a Windows XP installation that boots from a DOS installation on the C:\ drive. XP is on another partition of this drive, and boot.ini points to this partition by means of the string multi(0)disk(0)rdisk(0)partition(3)\Windows="Microsoft Windows XP Professional"

If I use Partition Magic to create another small partition for a Linux Boot partition below the XP partition, it will push XP up to partition(4), although the drive letter will not change.

Is there anything else that will be affected besides the entry in boot.ini (which I can edit)? Does any other part of the XP OS reference the partition number in such a way that a hidden Linux partition being inserted ahead of the OS partition will interfere with its operation?

Thanks in advance,

--torandson

 

[torandson]

Well,
Since no one responded, I tried an experiment. And the results were so useful that they should be posted here.

I am therefore unofficially renaming this thread to THE XP OS Backup Method!

Using the Partition Magic 8.0 bootable floppies, I copied the XP partition into an unallocated space on the other drive, and left it not hidden. Then I used a new entry in the boot.ini file to direct the startup process to that partition. The OS booted and ran even though it was now on a partition with a different drive letter. I don't see any problems yet.

In fact, by doing this and hiding the original partition, I was able to save the principle OS partition from Nero BackItUp directly to DVD, since the usual OS partition, being hidden, was therefore not being accessed by the backup OS running Nero. To my surprise, the backup OS partition (on Drive 1) assumed the same drive letter that the original OS partition (on drive 0) had been assigned when XP was first installed! This, despite the fact that there are other lettered partitions before and after both of these partitions. Cool. Way cool.

When I had first left the copy to the backup partition unhidden, I had also left the OS partition unhidden. In that case, the backup partition was given a drive letter higher than any other partitions, even higher than partitions above that partition on that drive. When I hid the original OS partition, though, its drive letter was then assigned to the backup partition on which the OS had been copied. The system didn't appear to know the difference when I booted to it. It was running the OS as usual, as far as Explorer was concerned. Very way cool!

This way, by having two partitions of the same size, I can use Partition Magic 8.0 on bootable floppies to copy the XP partition (which is not the C:\ partition) to its backup location, hide the original, leave the backup partition copy unhid, boot to the backup partition, save the original partition to DVD using Nero OEM that came with my Sony DVD-RW from within Windows XP!, run PM8.0 from floppies again and hide the backup, unhide the usual OS partition, and backing up the system now is so easy!

Now all I have to do is verify that after loading the original partition from DVD, it runs okay.

If I don't post back, it works fine.

--torandson

 

[wolluf]

what you've done is a well known fact! You have to be careful though - if you have both copies of XP unhidden when you first boot after copy, the second copy will NOT take C: (and so will not work properly - though it will boot, and work to a degree - in fact it will work ok while original is in place - except it will be using C: on original whenever its registry references C:.

Also, when you add partitions to a drive - even 'before' exisitng ones, the reference number in boot.ini doesn't necessarily change. The inserted one often takes a higher partition number (but you need to be aware that it may update the XP one, and be prepared to edit the boot.ini accordingly). When I used to play with mulit-booting, I used an XP 'boot floppy' (floppy with just ntdtect.com, ntldr and boot.ini on it) - where the boot.ini had selections for partitions 1-n and disks 1 or 2, so I could easily attempt to boot any partition.