Terms involved in backup/copy/clone operations and the limitations placed on the process by the Operating System.

Terms Involved in Disk Backup/Copy/Cloning:

Master Boot Record -
Also known as the "Primary Partition Table". The first sector on a hard disk. This is the data structure that starts the booting process of the computer. It is the most important area on a hard disk. The MBR contains the primary partition table and a small executable code (Master Boot Code) to interpret the logical contents of the remainder of the hard disk.

Primary Partition -
A section of a hard disk devoted to a particular file system or Operating System. Most hard disk contain one partition. A hard disk can contain as many as four partitions. Another name for Partition is Volume, and Partitions are assigned logical drive letters i.e. C: D: ...

Extended Partition -
A portion of a basic disk that contains logical drives. To have more then four volumes on a basic disk, you need to use an Extended Partition. Only one Extended Partition is allowed
per physical disk.

Boot Sector -
The first logical sector on a drive that contains disk parameter information for the Operating System. The Boot Sector also holds the bootstrap loader code that instructs the system how to load the Operating System files into memory.

Bootstrap Loader -
A program designed to bring itself to a desired state by means of its own action. In this context, the process by which the computer goes from an initial power on condition to a running condition without human intervention. With Windows NT based systems this process involved four processes: MBR->NTldr->Registry->Boot Record->WIN. This differs from old version of Windows which first booted to DOS then into Windows.

Disk-to-Disk (D2D) Copy -
A Disk is the entire physical device. Also known as a "Mirror Image", a D2D copy will copy the entire contents of the source disk. This copy will include all partitions from the source disk. All data on the target disk will be over written.

Logical Drive -
Also known as a "logical Volume". A logical drive created within a partition on a basic disk. You can format and assign a drive letter to a logical drive. Only basic disks can contain logical drives. A logical drive cannot span multiple disks.

Basic Disk -
A physical disk that contains primary and extended partitions with logical drives.

Dynamic Disk -
A physical disk that is managed by Disk Management. Dynamic Disks can contain only Dynamic Volumes. That is; Volumes created by Disk Management. Dynamic Disks cannot contain Partitions or logical drives nor can they be accessed by DOS. SEE Article #6 for more information on RAID arrays.

MFT (Master File Table) -
The database that tracks the contents of an NTFS volume.

Mount-Point -
Mount-points are drive letters that are created on an NTFS volume having a drive letter. Mount-Points can be assigned to a folder (C:\My Music) although it must exist on the root of a drive. In order to assign a Mount-Point for a volume as a path within another volume, the following criteria must be met: The volume must be formatted NTFS, A folder must exist at the root path, and the folder must be empty.

Windows Product Activation -
The method used to activate Windows Vista or XP for single-user licenses. When Windows is installed, the WPA system combines the Windows product ID and identification data from various hardware components (Display, SCSI, IDE, Network Adapters, Hard Disk Serial Numbers, Processor Types, and Serial Numbers). This combined ID (HWID) must be transmitted to Microsoft within 30 days of installation, then Microsoft returns the internal authorization that is stored in the operating system, making it valid. If more than six hardware components are replaced, the activation must be repeated.

HWID -
(Hardware IDentification) Starting with Windows XP and Vista, the Windows Product Activation (WPA) system was initiated, the HWID is a unique number generated when Windows is installed. It is derived from the current configuration of the hardware and the Windows XP product ID. A temporary HWID is generated each time the system is booted and is compared against the stored HWID. It is used to determine if the version of Windows has been moved to a different machine.

Limitations placed on the process by the Operating System:

Understanding and the proper Interpretation of all of the preceding terms are vital to creating a successful backup/copy/clone (D2D-Mirror Image) of a hard disk. The interrelationships of these disk objects must be maintained. This is the basic nature of the Windows XP (NT) Operating System. Without adherence to these disk objects the operating system will not function and cannot be copied.

• The LDCD (Logical Drive Configuration Database) is a database that is maintained at two locations. For basic disks and at boot time a temporary LDCD is generated based on the current hardware configuration. This is then compared against a copy of the LDCD in the registry. If data drives have been reassigned the temporary LDCD is written as the new LDCD (Note: links throughout the registry are not re-assigned with this change). If the boot disk has been re-assigned the NTldr will not be able to find disk objects and the system will not start most likely stating "Missing Operating System" upon boot. If the disk is a dynamic disk then a second copy is maintained within the last 1MB of each disk in the array. If the temporary copy of the LDCD does not match all of these copies and one or more of the array disks is involved then the dynamic drive will not mount.