Re: Partition logic?

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"Ron Hardin" <rhhardin@xxxxxxxxxxxxxx> wrote in message
news:438D34E0.4DD9@xxxxxxxxxxxxxxxxx
> If you create new partitions on the HD, what logic is used to
> determine which ``belong'' to windows?
>

Nothing "belongs" to Windows. All Windows does is assume every partition it
recognizes (e.g., FAT, FAT32, NTFS, etc.) is something it should provide
access to, and through Disk Management, initialize and assign a drive
letter.

> Do they get drive letters even if they belong to linux?
>

A partition has an "identifier", a small field in the MBR for that partition
that tells the OS its type. If Windows doesn't recognize the type, it
ignores that partition, at most you will see "unknown" partition under Disk
Management, but no ability to assign a drive letter (btw, that's how boot
managers like BootIt NG, Boot Magic, XOSL, etc., HIDE partitions!).

> For that matter, why don't other partitions that come with XP
> on dell, evidently swap and system restore, show up anywhere?
>

Because Dell has manipulated the indicator byte on the partition's entry in
the MBR such that the OS doesn't know what it is. When you use the recovery
CD, Dell's recovery system DOES, it copy the recovery partition in place of
your current partition, resets the partition indicator appropriately (e.g.,
FAT32, NTFS, whatever), and reboots. Whalla, you're in business again.

> Do the partitions have names or something in the MBR to say what
> to boot?
>

The MBR can hold up to FOUR partition addresses. Besides the "type"
indicator, there's an active/inactive field as well for each partition.
When that's set to ON, that partition is recognized as the bootable
partition. When the BIOS loads the first sector from the HD (which is the
MBR), the MBR boot code looks for the first partition marked active and
boots that partition based on the address stored there.

HTH

Jim

> --
> Ron Hardin
> rhhardin@xxxxxxxxxxxxxx
>
> On the internet, nobody knows you're a jerk.


.

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