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Disk Management

Published: November 03, 2005

Administrators can use the Disk Management snap-in or the new DiskPart command-line tool to manage disks and volumes in Microsoft Windows XP Professional. Both tools support dynamic disks and volumes, which were introduced in Microsoft Windows 2000. Microsoft Windows XP Professional x64 Edition also introduces a new disk partition type with greatly increased storage capacities, giving administrators additional choices for configuring disk storage.

For information on how to obtain the Windows XP Professional Resource Kit in its entirety, please see http://www.microsoft.com/mspress/books/6795.asp.

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On This Page

New in Disk Management
Disk Management Overview
Basic and Dynamic Disks and Volumes
Managing Volumes During Windows XP Professional Setup
Adding, Moving, and Importing Disks
Managing GPT Disks in 64-Bit Computers
Remote Disk and Command-Line Disk Management
Guidelines for Maintaining Disks and Volumes
Additional Resources

New in Disk Management

The Windows XP Professional operating system provides improved disk management. Table 12-1 summarizes the enhancements made from Microsoft Windows 2000 Professional to Windows XP Professional.

Table 12-1 Enhancements and Changes Since Windows 2000

New Feature

Feature Description

Manage disks at the command line by using DiskPart.

Use the new command-line tool DiskPart to perform disk-related tasks at the command line as an alternative to using the Disk Management snap-in. When you use DiskPart, you can create scripts to automate tasks, such as creating volumes or converting disks to dynamic.

Extend simple and spanned volumes that were converted from basic to dynamic.

You can now extend most simple and spanned volumes after converting them from basic to dynamic. For more information, see “Converting Basic Disks to Dynamic Disks” later in this chapter.

Extend basic volumes by using DiskPart.

Use DiskPart to extend primary partitions and logical drives on basic disks that use the MBR partition style.

Use a new partition style for disks in 64-bit computers.

Windows XP Professional x64 Edition supports a partition style called GUID partition table (GPT). The GPT partition style offers benefits such as support for volumes up to 18 exabytes and 128 partitions per disk.

Use NTFS when you format dynamic volumes and GPT disks by using Disk Management.

When you use the Disk Management snap-in, NTFS is the only file system available for dynamic volumes and for disks that use the GPT partition style. If you want to format dynamic volumes and GPT disks by using the file allocation table (FAT) file systems, you must use the format command at the command line.

Use dynamic disks to create volumes that span multiple disks.

Dynamic disks are the mandatory storage type for volumes that span multiple disks. Therefore, before you upgrade from Windows 2000 Professional to Windows XP Professional, you must convert basic disks to dynamic if they contain volume sets or stripe sets created by using Microsoft Windows NT Workstation 4.0.

If you are migrating from Microsoft Windows NT version 4.0, the enhancements in Table 12-2 apply in addition to those outlined in Table 12-1.

Table 12-2 Enhancements and Changes Since Windows NT 4.0

New Feature

Feature Description

Basic and dynamic disk storage

Windows XP Professional offers two types of disk storage: basic and dynamic. Basic disks use the same disk structures as those used in Windows NT 4.0.

Dynamic disks, which offer features not available in basic disks, were introduced in Windows 2000 and are supported and enhanced by Windows XP Professional.

Online disk management

You can perform most disk-related tasks without shutting down the computer or interrupting users, and most configuration changes take effect immediately. For example, you can create or extend a volume without restarting the computer. You can also add disks without restarting. For information about changes that do require restarting the computer, see “Converting Basic Disks to Dynamic Disks” later in this chapter.

Disk Management snap-in

The Disk Management snap-in replaces the Disk Administrator program used in Windows NT 4.0.

Local and remote disk management

By using the Disk Management snap-in, you can manage any remote computer running Windows 2000, Windows XP Professional, or Windows XP Professional x64 Edition on which you are a member of the Administrators group.

Limited support for multidisk volumes created by using Windows NT 4.0

Because Windows XP Professional offers limited support for multidisk volumes created by Windows NT 4.0, you must perform certain steps before you upgrade to Windows XP Professional. For more information, see “Preparing Multidisk Volumes for Windows XP Professional” later in this chapter.

Disk Management Overview

Use the Disk Management snap-in in Windows XP Professional to perform disk-related tasks, such as creating basic and dynamic volumes, formatting them, and assigning drive letters.

You must be a member of the Administrators group to use Disk Management.

To open Disk Management

  1. From the Start menu, click Run.

  2. In the Open box, type diskmgmt.msc, and then click OK.

    Note If you upgrade from Microsoft Windows 98, Microsoft Windows 98, Second Edition (SE), or Microsoft Windows Millennium Edition (Windows Me) to Windows XP Professional, a message appears when you open Disk Management during the first 30 days after installation. The message indicates that making any changes to your disk configuration, such as creating or deleting partitions or converting them to dynamic, prevents you from uninstalling Windows XP Professional. For more information, see Chapter 4, “Supporting Installations.”

After you install a new disk, you must choose a partition style and storage type to use on the disk. Your choices vary according to which operating system you are running and whether the computer is an x86-based computer or a 64-bit computer. Table 12-3 describes the storage types and partition styles that are available for each edition of Microsoft Windows XP and Windows 2000.

Table 12-3 Storage Types and Partition Styles Available in Windows XP and Windows 2000

Operating System

Storage Types

Storage Types

Storage Types

Partition Styles

Partition Styles

 

Basic Volumes

Dynamic Simple, Spanned, and Striped Volumes

Dynamic Mirrored and RAID-5 Volumes

MBR Disks

GPT Disks

Windows XP Home Edition

X

 

 

X

 

Windows XP Professional

X

X

 

X

 

Windows XP Professional x64 Edition

X

X

 

X

X

Windows 2000 Professional

X

X

 

X

 

Windows 2000 Server family

X

X

X

X

 

Windows Server™ 2003 family

X

X

X

X

X

Windows XP Professional offers two storage types: basic disk and dynamic disk. Basic disks use the same disk structures as those used in Windows Me or earlier, Microsoft Windows NT 4.0, and Microsoft Windows 2000. When using basic disks, you are limited to creating four primary partitions per disk, or three primary partitions and one extended partition with unlimited logical drives. Primary partitions and logical drives on basic disks are known as basic volumes.

Dynamic disks were introduced in Windows 2000 and are supported and enhanced by Windows XP Professional. Dynamic disks provide features that basic disks do not, such as the ability to create volumes that span multiple disks. All volumes on dynamic disks are known as dynamic volumes.

The term partition style refers to the method that Windows XP Professional uses to organize partitions on the disk. All x86-based computers use the partition style known as the master boot record (MBR). The MBR contains a partition table that describes where the partitions are located on the disk. Because MBR is the only partition style available on x86-based computers, you do not need to choose this style; it is used automatically.

64-bit computers running Windows XP Professional x64 Edition use a new partition style called the globally unique identifier (GUID) partition table (GPT). The GPT partition style supports partitions up to 18 exabytes and 128 partitions per disk.

The introduction of GPT makes understanding the partition styles a bit more challenging, but most disk-related tasks are unchanged. You can still use basic disks and dynamic disks as you did in Windows 2000, and these storage types are available on disks that use either partition style.

Disk Management differentiates between partition styles by referring to disks that use the master boot record as MBR disks and disks that use the GUID partition table as GPT disks. Figure 12-1 shows how Disk Management displays GPT and MBR disks in a 64-bit computer.

Note You can use Windows XP Professional x64 Edition to manage MBR disks and GPT disks. However, you cannot start Windows XP Professional x64 Edition from GPT disk.

Figure 12-1 How Disk Management displays GPT and MBR disks in a 64-bit computer

Figure 12-1 How Disk Management displays GPT and MBR disks in a 64-bit computer

For more information about GPT disks, see “Managing GPT Disks in 64-bit Computers” later in this chapter. For sector-level details about MBR and GPT disks, see Chapter 28, “Troubleshooting Disks and File Systems.”

Basic and Dynamic Disks and Volumes

You can use both basic and dynamic disks on the same computer system and with any combination of file systems. However, all volumes on a physical disk must be either basic or dynamic, and each disk must use either the MBR or GPT partition style. For more information about the file systems available in Windows XP Professional, see Chapter 13, “Working with File Systems.”

Basic Disks

The term basic disk refers to a physical disk that contains basic volumes, such as primary partitions and logical drives. In x86-based computers, basic disks use the same partition style (the MBR partition style) as the disks used by Microsoft MS-DOS, Windows Me or earlier, Windows NT 4.0 or earlier, and Windows 2000. Therefore, use basic disks if you want to use these operating systems to access data locally on an x86-based computer that also runs Windows XP Professional (which is known as a multiboot scenario).

64-bit computers also support basic disks, but you can choose either partition style (MBR or GPT) for each basic disk. The partition style determines the number of basic volumes you can create on the disk as well as the operating systems that can access the disk. For more information about GPT disks, see “Managing GPT Disks in 64-bit Computers” later in this chapter.

You must convert a basic disk to dynamic before you can create simple volumes, spanned volumes, and striped volumes. For more information, see “Converting Basic Disks to Dynamic Disks” later in this chapter.

Basic Volumes

The term basic volume refers to a partition on a basic disk. Windows XP Professional supports the following basic volumes:

  • Primary partitions (MBR and GPT disks)

  • Logical drives within extended partitions (MBR disks only)

The number of basic volumes you can create on a basic disk depends on the partition style of the disk:

  • On MBR disks, you can create up to four primary partitions, or you can create up to three primary partitions and one extended partition. Within the extended partition, you can create unlimited logical drives.

  • On GPT disks, you can create up to 128 partitions. Because GPT disks do not limit you to four partitions, extended partitions and logical drives are not available on GPT disks. For more information about GPT disks, see “Managing GPT Disks in 64-bit Computers” later in this chapter.

If you want to add more space to existing primary partitions and logical drives, use the extend command in DiskPart. The requirements for extending a basic volume are as follows:

  • You must use NTFS to format the basic volume. If the volume is formatted by using FAT, you must convert it to NTFS before you can extend it. For more information about converting FAT volumes to NTFS, see Chapter 13, “Working with File Systems.”

  • You can extend a basic volume on the same disk only, and the basic volume must be followed by contiguous unallocated space.

  • You can extend a logical drive within contiguous free space in the extended partition that contains it. If you extend a logical drive beyond the free space available in the extended partition, the extended partition grows to contain the logical drive as long as the extended partition is followed by contiguous unallocated space.

For more information about using DiskPart, see Windows XP Professional Help.

Dynamic Disks

A dynamic disk is a physical disk that contains dynamic volumes. Dynamic disks provide features that basic disks do not. For example, use dynamic disks if you need to:

  • Increase the size of a volume by extending the volume onto the same disk by using unallocated space that is not contiguous. You can also extend a volume onto other dynamic disks.

  • Improve disk input/output (I/O) performance by using striped volumes.

Dynamic disks offer greater flexibility for volume management because they use a hidden database to track information about dynamic volumes on the disk and about other dynamic disks in the computer. Because each dynamic disk in a computer stores a replica of the dynamic disk database, Windows XP Professional can repair a corrupted database on one dynamic disk by using the database on another dynamic disk.

The location of the database is determined by the partition style of the disk.

  • On MBR disks, the database is contained in the last 1 megabyte (MB) of the disk.

  • On GPT disks, the database is contained in a 1-MB reserved (hidden) partition known as the Logical Disk Manager (LDM) Metadata partition.

When you move dynamic disks to a computer that has existing dynamic disks, you must import the dynamic disks to merge the databases on the moved disks with the databases on the existing dynamic disks. For more information about importing dynamic disks, see “Importing Foreign Disks” later in this chapter.

All dynamic disks in a computer must be members of the same disk group, which is a collection of dynamic disks. Each disk in a disk group stores a replica of the same dynamic disk database. A disk group uses a name consisting of the computer name plus a suffix of Dg0. The disk group name is stored in the registry.

The disk group name on a computer never changes as long as the disk group contains dynamic disks. If you remove the last disk in the disk group or convert all dynamic disks to basic, the registry entry remains. However, if you then create a dynamic disk again on that computer, a new disk group name is generated. The computer name in the disk group remains the same, but the suffix is Dg1 instead of Dg0.

When you move a dynamic disk to a computer that has no dynamic disks, the dynamic disk retains its disk group name and ID from the original computer and uses them on the local computer.

For more information about disk groups, see article 222189, “Description of Disk Groups in Windows 2000 Disk Management,” in the Microsoft Knowledge Base. To find this article, see the Microsoft Knowledge Base link on the Web Resources page at http://www.microsoft.com/windows/reskits/webresources.

For more information about converting basic disks to dynamic, including the limitations of dynamic disks, see “Converting Basic Disks to Dynamic Disks” later in this chapter.

Dynamic Volumes

A dynamic volume is a volume that is created on a dynamic disk. Dynamic volume types include simple, spanned, and striped volumes. Windows 2000 Server and Windows Server 2003 also supports mirrored and RAID-5 volumes, which are fault tolerant. Dynamic disks and volumes are not available on computers running Windows XP Home Edition.

Regardless of the partition style used (MBR or GPT), you can create about 2,000 dynamic volumes per disk group, although the recommended number of dynamic volumes is 32 or fewer per disk group.

To help you understand dynamic volumes, the following descriptions are provided.

Simple Volumes

Simple volumes are the dynamic-disk equivalent of the primary partitions and logical drives that you used in Windows NT 4.0 and earlier versions. When creating simple volumes, keep these points in mind:

  • If you have only one dynamic disk, you can create only simple volumes.

  • You can increase the size of a simple volume to include unallocated space on the same disk or on a different disk. The volume must be unformatted or formatted by using NTFS. You can increase the size of a simple volume in two ways:

    • By extending the simple volume on the same disk. The volume remains a simple volume.

    • By extending a simple volume to include unallocated space on other disks on the same computer. This creates a spanned volume.

      Note If the simple volume is the system volume or the boot volume, you cannot extend it. For more information about determining which volumes are the system and boot volumes, see “Converting Basic Disks to Dynamic Disks” later in this chapter.

Spanned Volumes

Spanned volumes combine areas of unallocated space from multiple disks into one logical volume. The areas of unallocated space can be different sizes. Spanned volumes require at least two disks, and you can use up to 32 disks. When creating spanned volumes, keep these points in mind:

  • You can extend only NTFS volumes or unformatted volumes.

  • After you create or extend a spanned volume, you cannot delete any portion of it without deleting the entire spanned volume.

  • You cannot stripe spanned volumes.

  • Spanned volumes do not provide fault tolerance. If one of the disks containing a spanned volume fails, the entire volume fails, and all data on the spanned volume becomes inaccessible.

Striped Volumes

Striped volumes improve disk I/O performance by distributing I/O requests across multiple disks. Striped volumes are composed of stripes of data of equal size written across each disk in the volume. They are created from equally sized, unallocated areas on two or more physical disks. In Windows XP Professional, the size of each stripe is 64 kilobytes (KB).

Striped volumes cannot be extended and do not offer fault tolerance. If one of the disks containing a striped volume fails, the entire volume fails, and all data on the striped volume becomes inaccessible.

Mirrored Volumes

A mirrored volume is a fault-tolerant volume that provides a copy of a volume on another physical disk. Mirrored volumes provide data redundancy by duplicating the information contained on the volume. The two volumes that make up a mirrored volume are known as mirrors. Each mirror is always located on a different disk. If one of the physical disks fails, the data on the failed disk becomes unavailable, but the system continues to operate by using the unaffected disk.

Mirrored volumes are available only on computers running the Windows 2000 Server and Windows Server 2003 operating system families. Mirrored volumes are not available on computers running Windows XP.

RAID-5 Volumes

A RAID-5 volume is a fault-tolerant volume that stripes data and parity across three or more physical disks. Parity is a calculated value that is used to reconstruct data if one physical disk fails. When a disk fails, the volume continues to operate by re-creating the data that was on the failed disk from the remaining data and parity.

RAID-5 volumes are available only on computers running the Windows 2000 Server and Windows Server 2003 operating system families. RAID-5 volumes are not available on computers running Windows XP.

Converting Basic Disks to Dynamic Disks

You can convert a basic disk to dynamic by using Disk Management or by using DiskPart, a command-line tool that provides the same functions as Disk Management.

When you convert a disk to dynamic, the following events occur:

  • All existing primary partitions and logical drives become simple volumes.

  • The disk joins the local disk group and receives a copy of the dynamic disk database.

Before you convert a disk to dynamic, read the section “Before Converting Disks to Dynamic” later in this chapter to review the scenarios that are affected by dynamic disks. For example, converting disks to dynamic in a multiple-boot computer can cause startup problems if you do not configure your disks properly. If you decide to perform the conversion, see “How to Convert a Basic Disk to Dynamic” later in this chapter.

Note For certain disks, the menu command to convert the disk to dynamic is unavailable in Disk Management. For more information, see “Disks That You Cannot Convert to Dynamic” later in this chapter.

You can convert basic disks to dynamic at any time. In most cases, you do not need to restart your computer to complete the conversion. However, you must restart the computer if the disks you are converting contain any of the following volumes:

  • System volume

    The system volume contains hardware-specific files such as Ntldr, Boot.ini, and Ntdetect.com. These files are needed to load Windows XP Professional. These files cannot reside on a GPT Disk.

  • Boot volume

    The boot volume contains the Windows XP Professional operating system and its support files. The boot volume can be, but does not have to be, the same volume as the system volume.

  • Volumes that contain the paging file

    The paging file is a hidden file on the hard disk that Windows XP Professional uses to hold parts of programs and data files that do not fit in memory.

    Warning When you convert MBR disks that contain the system, boot, or paging file volumes to dynamic, you are prompted to restart the computer two times. You must restart the computer twice to complete the conversion.

As shown in Figure 12-2, the Disk Management snap-in identifies these volumes in the graphical and disk list views. If you have a combined system and boot volume that also contains the paging file (the most common scenario), only System is shown.

Figure 12-2 How Disk Management identifies separate system, boot, and paging file volumes for an x86-based computer

Figure 12-2 How Disk Management identifies separate system, boot, and paging file volumes for an x86-based computer

The list volume command in DiskPart also shows the system, boot, and paging file volumes as follows:

Volume ###  Ltr  Label        Fs     Type        Size     Status     Info 
----------  ---  -----------  -----  ----------  -------  ---------  -------- 
Volume 0     G                       Unknown         0 B 
Volume 1     C                NTFS   Partition   4096 MB  Healthy    System 
Volume 2     F                NTFS   Partition   4651 MB  Healthy 
Volume 3     D                NTFS   Partition   4096 MB  Healthy    Boot 
Volume 4     P                NTFS   Partition   4664 MB  Healthy    Pagefile 
Volume 5     E                NTFS   Partition      9 GB  Healthy

For more information about using DiskPart, see “Managing Disks from the Command Line by Using DiskPart” later in this chapter.

Even after you convert a disk to dynamic, some types of primary partitions do not become dynamic volumes. These partitions retain their partition entries in the partition table and are shown as primary partitions in Disk Management. These partitions are:

  • Known OEM partitions (usually displayed in Disk Management as EISA Configuration partitions)

Before Converting Disks to Dynamic

Converting a disk to dynamic changes the partition layout on the disk and creates the dynamic disk database. The result of these changes is increased flexibility for volume management in Windows XP Professional. However, these changes are not easily reversed, and the structure of dynamic disks is not compatible with some operating systems. Therefore, you must consider the following issues before you convert disks to dynamic.

If you want to uninstall Windows XP Professional

Do not convert a disk to dynamic if you upgraded from Windows 98 or Windows Me, and you later want to uninstall Windows XP Professional and revert to your previous operating system. Making any changes to disk configuration, including converting a disk to dynamic, prevents you from uninstalling Windows XP Professional. For more information, see Chapter 4, “Supporting Installations.”

If a disk contains multiple copies of Windows XP Professional, Windows 2000, or Windows Server 2003

Do not convert a disk to dynamic if it contains multiple copies of Windows XP Professional, Windows 2000, or Windows Server 2003. Even though these operating systems support dynamic disks, they require certain registry entries that allow them to start from dynamic disks. If the operating systems are installed on the same disk and you use one of the operating systems to convert the disk to dynamic, the registry of the other operating system becomes out of date because the drivers required to start the operating system from a dynamic disk are not loaded. Therefore, you can no longer start the other operating system.

One way that you can use dynamic disks with Windows XP Professional, Windows 2000, and Windows Server 2003 in a multiple-boot configuration is to install each operating system to a different disk. For example, install Windows 2000 on disk 1 and Windows XP Professional on disk 2. Use Windows 2000 to convert disk 1 to dynamic, and then use Windows XP Professional to convert disk 2 to dynamic. By using this method, you ensure that the registries are updated for each operating system.

If you want to access the disk by using Windows Me or earlier, or Windows NT 4.0

You can access dynamic disks only from computers that are running Windows 2000, Windows Server 2003, Windows XP Professional, or Windows XP Professional x64 Edition. You cannot access dynamic disks from computers running MS-DOS, Windows 95, Windows 98, Windows Me, Windows NT 4.0 or earlier, or Windows XP Home Edition. This restriction also means that you cannot start any of these operating systems if you convert the disk containing the system volume to dynamic.

To avoid this restriction, use two hard disks: install the other operating system on the first disk, which contains the system volume, and then install Windows XP Professional on the second disk. Using this method, you can convert the disk that is running Windows XP Professional to dynamic and still start the other operating system on the basic disk. However, this method prevents the other operating system from accessing the dynamic disk or any of its volumes and data. Therefore, in computers that start multiple operating systems, you must use caution when you convert disks to dynamic.

Access to dynamic disks is further restricted by the partition style used on the dynamic disk:

  • Dynamic MBR disks

    Only computers running Windows 2000, Windows Server 2003, Windows XP Professional, or Windows XP Professional x64 Edition can access dynamic MBR disks.

  • Dynamic GPT disks

    Only computers running Windows XP Professional x64 Edition or Windows Server 2003 can access dynamic GPT disks.

    Note Volumes on dynamic MBR and GPT disks are available across a network to computers running any Microsoft operating system.

If the disk contains partitions displayed as Healthy (Unknown) in Disk Management

Do not convert a disk to dynamic if it contains unknown partitions created by other operating systems. Windows XP Professional converts unknown partitions to dynamic, making them unreadable to other operating systems. For more information about unknown partitions, see Chapter 28, “Troubleshooting Disks and File Systems.”

If the disk contains an OEM partition that is not at the beginning of the disk

Do not convert a disk to dynamic if it contains an OEM partition that is not at the beginning of the disk. (In Disk Management, an OEM partition usually appears as an EISA Configuration partition.) When you convert a disk to dynamic, Windows XP Professional preserves the OEM partition only if it is the first partition on the disk. Otherwise, the partition is deleted during the conversion to dynamic.

If you want to extend a dynamic volume

You can extend dynamic volumes that do not retain their partition entries in the partition table. The following volumes retain their entries in the partition table and cannot be extended:

  • The system volume and boot volume of the operating system that you used to convert the disk to dynamic.

  • Any basic volume that was present on the disk when you converted the disk from basic to dynamic by using the version of Disk Management included with Windows 2000.

  • Simple volumes on which you run the DiskPart command retain. The retain command adds a partition entry to the partition table. However, after you use this command, you can no longer extend the volume.

    Note The retain command adds an entry to the partition table of an MBR disk only for simple volumes that are contiguous, start at cylinder-aligned offsets, and are an integral number of cylinders in size. If a volume does not meet these requirements, the retain command fails. The following examples describe volumes on which the retain command will succeed:

    • The simple volume is contiguous and starts at the beginning of the disk.

    • The simple volume was present on the disk when the disk was converted to dynamic.

The only way to add more space to the system or boot volume on a dynamic disk is to back up all data on the disk, repartition and reformat the disk, reinstall Windows XP Professional, convert the disks to dynamic, and then restore the data from backup.

The following volumes do not have partition entries and can therefore be extended:

  • Simple volumes and spanned volumes created from unallocated space on a dynamic disk.

  • A basic volume that is not the system or boot volume and that is on a disk that was converted from basic disk to dynamic disk by using Windows XP Professional.

In addition, you cannot extend striped volumes. Although striped volumes do not have entries in the partition table, Windows XP Professional does not support extending them. You can add more space to a striped volume by backing up the data, deleting the volume, re-creating the volume by using Windows XP Professional, and then restoring the data.

If you want to install Windows XP Professional on a dynamic volume

You can install Windows XP Professional only on dynamic volumes that retain their partition entries in the partition table. The only dynamic volumes listed in the partition table are the following:

  • The system volume and boot volume of the operating system (Windows XP Professional or Windows 2000) that you used to convert the disk to dynamic. The system volume and boot volume must be simple volumes.

  • Any basic volume that was present on the disk when you used Windows 2000 to convert the disk from basic to dynamic.

  • Simple volumes on which you run the DiskPart command retain. The retain command adds a partition entry to the partition table so that you can install Windows XP Professional on the simple volume.

Because these dynamic volumes retain their partition entries, you can install Windows XP Professional on them. However, you cannot extend any of these volumes because you can only extend volumes that do not have entries in the partition table.

If you want to format a dynamic volume by using FAT

Disk Management does not offer FAT as a formatting option for dynamic volumes because NTFS is the preferred file system for dynamic volumes. If you want to format a dynamic volume by using FAT, you must use My Computer, Windows Explorer, or the format command. For more information about FAT and NTFS, see Chapter 13, “Working with File Systems.”

How to Convert a Basic Disk to Dynamic

After you review the section “Before Converting Disks to Dynamic” earlier in this chapter, you can use this procedure to convert a basic disk to dynamic.

To convert a basic disk to dynamic by using Disk Management
  1. From the Start menu, click Run.

  2. In the Open box, type diskmgmt.msc, and then click OK.

  3. Right-click the disk you want to convert to dynamic, and then click Convert to Dynamic Disk.

    Make sure that you right-click the disk, not a volume on the disk. If the Convert to Dynamic Disk command is unavailable or if the conversion fails, you cannot convert the disk to dynamic. For more information, see “Disks That You Cannot Convert to Dynamic” later in this chapter.

Although you can convert a basic disk to dynamic without losing data, you cannot convert a dynamic disk to basic if the disk contains volumes. You must delete all volumes on a dynamic disk before you can convert it to basic. If you want to keep your data, you must back it up or move it to another disk before you delete the volumes. After you convert the disk to basic, you can create a new partition that uses the same drive letter or drive path that you used with the dynamic volume and then restore the data. For more information about drive paths and mounted drives, see Windows XP Professional Help.

To convert an unpartitioned dynamic disk to basic
  • In Disk Management, right-click the dynamic disk, and then click Convert to Basic Disk.

Disks That You Cannot Convert to Dynamic

Windows XP Professional Setup and Disk Management ensure that disks initialized by Windows XP Professional can be converted to dynamic. However, on some disks the conversion fails or the Convert to Dynamic Disk command is not available when you right-click a basic disk. The following conditions prevent you from converting a basic disk to dynamic.

The computer is running Windows XP Home Edition

Dynamic disks are not available on computers running Windows XP Home Edition.

The disk is in a portable computer

Windows XP Professional does not support dynamic disks in portable computers. However, on some older portable computers that are not Advanced Configuration and Power Interface (ACPI) compliant, you might be able to convert the disk to dynamic, but it is neither recommended nor supported.

The disk is a removable disk

You cannot use dynamic disks on the following:

  • Removable media, such as Iomega Zip or Jaz disks

  • Detachable disks that use universal serial bus (USB) or IEEE 1394 (also called FireWire) interfaces

The sector size is larger than 512 bytes

A sector is a unit of storage on a hard disk. The majority of hard disks use 512-byte sectors. Windows XP Professional supports converting basic disks to dynamic only if the sector size of the basic disk is 512 bytes.

Partitions on a GPT disk are not contiguous

If an unknown partition lies between two known partitions on a GPT disk, you cannot convert the disk to dynamic. Unknown partitions are created by operating systems or utilities that use partition-type GUIDs that Windows XP Professional x64 Edition does not recognize. For more information about partition type GUIDs supported by Windows XP Professional x64 Edition, see Chapter 28, “Troubleshooting Disks and File Systems.”

An MBR disk does not have space for the dynamic disk database

An MBR disk requires 1 MB of disk space at the end of the disk to be used for the dynamic disk database. Windows XP Professional and Windows 2000 automatically reserve 1 MB or one cylinder, whichever is greater, when creating partitions on a disk, but in rare cases, disks with partitions created by other operating systems might not have this space available. If this space is not available, you cannot convert the disk to dynamic.

To convert the disk to dynamic, you must back up or move the data, delete the partitions, recreate the partitions, restore the data, and then convert the disk to dynamic. By using Windows XP Professional to create the partitions, you ensure that the necessary space is available for the dynamic disk database.

This limitation does not affect GPT disks because the database is created in its own partition with space borrowed from the Microsoft Reserved partition. For more information about the Microsoft Reserved partition, see “Required Partitions on GPT Disks” later in this chapter.

Managing Volumes During Windows XP Professional Setup

Before you begin Windows XP Professional Setup on an x86-based computer, either as a new installation or as an upgrade, review your current disk configuration and determine whether you need to create additional volumes during Setup. Because your options for creating and formatting volumes are limited during Setup, you might want to create only the system and boot volumes during Setup, and then wait until Setup completes before you create and format additional volumes.

If your computer uses multidisk volumes created by using Windows NT 4.0, you must follow the guidelines provided in the next section.

Warning If you upgrade from Windows 98 or Windows Me to Windows XP Professional, do not make any changes to your disk configuration after Setup completes if you want to uninstall Windows XP Professional and revert to the previous operating system. For example, converting a volume to NTFS, converting a disk to dynamic, or deleting volumes can prevent you from uninstalling Windows XP Professional. For more information, see Chapter 4, “Supporting Installations.”

To ensure that you can successfully install Windows XP Professional, you must verify that the computer’s mass storage controllers—such as Advanced Technology Attachment (ATA), IDE, SCSI, RAID, or Fibre Channel adapters—are supported by Windows XP. You might also need to obtain from the device manufacturer a separate device driver for use with Windows XP Professional. After you obtain the device driver, copy it to a floppy disk before you begin Setup. During the early part of Setup, a line of text at the bottom of the screen prompts you to press F6. Additional prompts help you install the device driver so that Setup can gain access to the mass storage controller.

If you are unsure whether Windows XP Professional supports your mass storage controller, you can try running Setup. If the controller is not supported, you receive the Stop message 0x7B INACCESSIBLE_BOOT_DEVICE.

For more information about supported hardware, see the Windows Catalog at http://www.microsoft.com/windows/catalog.

Preparing Multidisk Volumes for Windows XP Professional

Ftdisk.sys was the fault-tolerant driver that was used to manage volume sets and striped sets in Windows NT Workstation 4.0 and earlier. To encourage administrators to begin using dynamic volumes, Windows 2000 offered limited support for Ftdisk volumes. Completing this transition, Windows XP Professional does not support volume sets or striped sets. Therefore, before you install Windows XP Professional on an x86-based computer, you must do one of the following:

  • If you are upgrading from Windows NT Workstation 4.0 to Windows XP Professional, you need to back up and then delete all multidisk volumes before you upgrade because Windows XP Professional cannot access these volumes. Be sure to verify that your backup was successful before deleting the volumes. After you finish upgrading to Windows XP Professional, create new dynamic volumes and then restore the data.

    If you do not back up the volumes before you upgrade to Windows XP Professional, Disk Management shows the volumes as Failed. You must use Ftonline.exe to restore the volumes to Healthy so that you can access data on them. Access is valid only for the current session so that you can back up the data before you delete the volumes. If you reboot, you must run Ftonline again. For more information about using Ftonline.exe, click Tools in Help and Support Center, and then click Windows Support Tools.

    Note Before you can upgrade a computer that is running Windows NT 4.0 to Windows XP Professional, you must first install Service Pack 6 or later.

  • If you are upgrading from Windows NT Workstation 4.0 to Windows XP Professional and the paging file resides on a volume set or striped set, you must use System in Control Panel to move the paging file to a primary partition or logical drive before beginning Setup.

  • If you are upgrading from Windows 2000 Professional to Windows XP Professional, you must use Disk Management to convert all basic disks that contain multidisk volumes to dynamic disks before beginning Setup or Setup does not continue.

Creating Volumes During Windows XP Professional Setup

During Windows XP Professional Setup, you can create basic volumes by using unallocated space from the basic disks that are installed in the computer. For example, on a single unformatted hard disk, you can create a system volume and separate boot volume, or you can create a single combined system and boot volume that uses all unallocated space on the disk. You can also create additional basic volumes on the same disk and on other disks in the computer if unallocated space is available. However, you cannot create additional volumes on dynamic disks during Setup.

Although you can specify the size of each basic volume, you cannot specify whether to create a primary partition, extended partition, or logical drive. Setup determines the type of volume as follows:

  • If no partitions exist on the disk, Setup creates a primary partition of the size you specified.

  • If a single primary partition exists, Setup creates an extended partition by using the remaining contiguous, unallocated space on the disk. Setup then creates a logical drive (within the extended partition) of the size you specified.

  • If a primary partition and an extended partition exist on the disk and no free space exists within the extended partition, Setup creates an additional primary partition of the size you specified.

    Note When you create basic volumes during Setup, Setup reserves 1 MB or one cylinder, whichever is greater, at the end of the disk. Setup reserves the space for the dynamic disk database so that you can convert the disk to dynamic if you want to.

After you create each volume, Setup assigns it a drive letter. The drive letter that Setup chooses depends on whether other basic volumes, dynamic volumes, and removable disks have drive letters already assigned. For all volumes and removable disks without drive letters, Setup assigns drive letters by using the following method:

  1. Scans all fixed hard disks as they are enumerated. Assigns drive letters starting with any active primary partition (if one exists); otherwise, scans the first primary partition on each disk. Assigns the next available letter, starting with C.

  2. Scans all fixed hard disks and removable disks, and assigns drive letters to all logical drives in an extended partition or the removable disks as enumerated. Assigns the next available letter, starting with C.

  3. Scans all fixed hard disks, and assigns drive letters to all remaining primary partitions. Assigns the next available letter, starting with C.

  4. Scans floppy drives, and assigns the next available drive letter, starting with A.

  5. Scans CD-ROM drives, and assigns the next available letter, starting with D.

Windows XP Professional and Windows 2000 assign drive letters differently from how Windows 98, Windows Me, and Windows NT 4.0 assign drive letters. Therefore, if the computer starts multiple operating systems, the drive letters might vary depending on which operating system is running. For more information about how Windows XP Professional and Windows 2000 assign drive letters, see the Microsoft Knowledge Base link on the Web Resources page at http://www.microsoft.com/windows/reskits/webresources. Search the Knowledge Base by using the keywords “LDM” and “cmdcons”.

If an existing removable disk is not turned on during Setup, Windows XP Professional might give its drive letter to a new volume. For example, if a removable disk had drive letter G in Windows 2000 but was turned off during Windows XP Professional Setup, a newly created volume might be given drive letter G. To ensure that drive letter assignments remain constant, you must keep removable disk devices turned on when you create new volumes.

After Setup is complete, you can change drive letters for most volumes and removable disks by using Disk Management or the DiskPart command-line tool.

To change a drive letter by using Disk Management
  1. From the Start menu, click Run.

  2. In the Open box, type diskmgmt.msc, and then click OK.

  3. Right-click the volume whose drive letter you want to change, and then click Change Drive Letter and Paths.

  4. Click Change, and then select the drive letter you want to use.

    Note You can assign drive letters A and B to removable disks, such as Iomega Zip drives, and also to floppy drives. You cannot assign these drive letters to fixed hard disks.

For information about using DiskPart to change drive letters, see Windows XP Professional Help.

You cannot use Disk Management to change the drive letter of the system or boot volumes. Instead, you must change the drive letter by making certain changes in the registry. This procedure is not recommended unless you are changing the drive letter back to the original letter.

For more information about changing the drive letter of the system or boot volume, see the Microsoft Knowledge Base link on the Web Resources page at http://www.microsoft.com/windows/reskits/webresources. Search the Knowledge Base by using the keywords “mounted”, “devices”, and “partition”.

For more information about formatting volumes during Setup, see Chapter 13, “Working with File Systems.”

Installing Windows XP Professional on Dynamic Disks

You can install Windows XP Professional on the following dynamic volumes:

  • Any basic volume that was present on the disk when you converted the disk to dynamic by using Windows 2000.

  • Simple volumes on which you run the DiskPart command retain. This command adds a partition entry to the partition table so that you can install Windows XP Professional on the simple volume.

    Note The DiskPart retain command adds an entry to the partition table of an MBR disk only for simple volumes that are contiguous, start at cylinder-aligned offsets, and are an integral number of cylinders in size. If a volume does not meet these requirements, the retain command fails. The following examples describe volumes on which the retain command will succeed:

    • The simple volume is contiguous and starts at the beginning of the disk.

    • The simple volume was present on the disk when the disk was converted to dynamic.

  • An existing simple volume that is the boot or system volume.

    Caution Do not install Windows XP Professional on a mirrored system or boot volume. Although the installation completes successfully, Windows XP Professional cannot start because it does not support mirrored volumes.

During a new installation of Windows XP Professional, Setup displays a list of all disks and volumes installed in the computer. However, Setup does not differentiate between basic and dynamic disks, nor does Setup differentiate between installable and noninstallable dynamic volumes. Therefore, before you begin Setup, decide which volume you plan to install Windows XP Professional on, and then ensure that the volume is installable.

If you choose a dynamic volume that is not installable, Setup displays a message that the partition is unrecognized and that you cannot install Windows XP Professional on it.

Caution Use caution when deleting volumes during Setup, especially if the computer contains dynamic disks. Deleting a single dynamic volume during Setup deletes all volumes on the disk and converts the disk to basic. As a result, all data on the disk is lost.

If you want to delete a dynamic volume without causing all other dynamic volumes on the disk to become inaccessible, wait for Setup to complete, and then use the Disk Management snap-in to delete the volume.

If you try to delete a dynamic volume during Setup, you are warned about this issue before any data is destroyed. You can then choose to continue with the deletion, which deletes all volumes and their data, or cancel the deletion.

For more information about installing Windows XP Professional on dynamic volumes, see “Converting Basic Disks to Dynamic Disks” earlier in this chapter.

Adding, Moving, and Importing Disks

As you administer disk storage, you might need to add new hard disks or move hard disks from one computer to another. If a hard disk fails, you need to remove it and replace it with a new hard disk. After you connect the hard disk to the computer, you must perform certain steps before you can access or create volumes on the disk.

This section discusses the following:

  • Adding new disks to a computer

  • Moving and removing disks

  • Importing foreign disks

Adding New Disks to a Computer

When you first start Disk Management after installing a new hard disk, a wizard appears that provides a list of the new disks detected by Windows XP Professional. Follow the instructions in the wizard to initialize the disk by creating the partition structures, such as the MBR or the GUID partition table, necessary for data storage.

Next, the wizard offers to convert the disks to dynamic. Click to select the check box next to each disk that you want to convert to dynamic, and then follow the instructions to complete the wizard.

Note If you cancel the wizard before the partition structures are written, the disk status remains Not Initialized until you right-click the disk, and then click Initialize Disk.

After you complete the wizard that installs the disk, the Plug and Play Manager assigns a number to the disk, which appears in Disk Management. The disk numbers are not necessarily assigned in a certain order, and disk numbers might change after you restart the computer.

For more information about Plug and Play Manager, see Chapter 9, “Managing Devices.”

Moving Disks

You can move basic and dynamic disks from one computer to another. For example, if a computer becomes inoperable but you know the hard disk still works, you can move the disk to a computer that is running Windows XP Professional and access the data on the disk.

Before You Move Disks

Before you move disks and install them in a computer that is running Windows XP Professional, you must review these guidelines.

If you are moving dynamic disks

Do not move dynamic disks to computers running Windows 95, Windows 98, Windows Me, Windows NT 4.0 or earlier, or Windows XP Home Edition because these operating systems cannot read dynamic disks. If you want to make the disk readable by an operating system that cannot read dynamic disks, you must use Windows XP Professional or Windows 2000 to back up or move the data to another disk, delete all volumes, and then right-click the dynamic disk and click Convert to Basic Disk.

If you are moving disks that contain multidisk volumes

Move all disks that contain multidisk volumes, such as spanned and striped volumes, at the same time. If you move only one disk and leave the other disk in the original computer, the data in the striped or spanned volumes becomes inaccessible on both disks. You must move the disks at the same time to ensure the data is accessible on the target computer. For more information about moving multidisk volumes, see “Importing Foreign Disks” later in this chapter.

If you are moving GPT disks

Move GPT disks only to other 64-bit computers because x86based computers cannot read the partition structures on the disk. If you move a GPT disk to an x86-based computer running Windows 2000 with Service Pack 1 or greater or Windows XP Professional, the Disk Management snap-in shows that the GPT disk contains one volume with the status GPT Protective Partition. However, you cannot access any data on the GPT disk nor can you delete the volume. As a result, the disk is unusable in any x86-based computer unless you convert the disk to an MBR disk.

In Windows XP Professional, you can convert a GPT disk to MBR by using the clean command in DiskPart, which removes all data and partition structures from the disk. You cannot use the Disk Management snap-in in Windows XP Professional to perform the conversion. However, you can use Disk Management in Windows XP Professional x64 Edition to convert a GPT disk to an MBR disk and vice versa, but the disk must be empty. For more information about changing the partition style of a disk, see “Managing GPT Disks in 64-Bit Computers” later in this chapter.

If the disk contains volume sets or stripe sets

Windows XP Professional cannot access volume sets or striped sets that were created by using Windows NT 4.0. If you must move disks that contain volume sets or striped sets to Windows XP Professional, you have three choices:

  • You can back up and then delete these volumes before you move the disks, and then create new dynamic volumes and restore the data.

  • If the volume sets or striped sets are in a computer running Windows 2000 Professional, you can convert the disks that contain them to dynamic before you move the disks to a computer running Windows XP Professional. If you use this method, it is recommended that you back up the data as a precaution before converting the disks to dynamic. After you move the disks, Windows XP Professional can access them normally.

  • If the volume sets or striped sets are in a computer running Windows NT 4.0, you can use the command-line tool Ftonline.exe after you move the disks to access the volumes in Windows XP Professional. Access is valid only for the current session so that you can back up the data before you delete the volumes. If you reboot, you must run Ftonline again. For more information about using Ftonline.exe, click Tools in Help and Support Center, and then click Windows Support Tools.

Do not move disks that contain mirror sets or striped sets with parity to a computer running Windows XP Professional. You can, however, move disks from computers running Windows NT 4.0 to computers running Windows XP Professional if the disks contain primary partitions, extended partitions, and logical drives.

If the dynamic disk contains the system or boot volume

Do not move a dynamic disk that contains the system or boot volume to another computer unless you have no other way to recover data. Startup problems can occur if you move the disk back to the original computer and attempt to start Windows XP Professional from the disk.

You can, however, move a basic disk that contains a system or boot volume to another computer, access data on the disk, and then move the disk back to the original computer and successfully start Windows XP Professional.

If the target computer has no dynamic disks

If you move a dynamic disk that does not contain a system or boot volume to a computer that has never contained dynamic disks, the target computer uses the disk group identity from the original computer. This is not a problem unless you try to move the disk back to the original computer, and the original computer contains other dynamic disks. In this case, the original computer cannot import the foreign disk. To resolve this problem, move the disk to a different computer that has an existing disk group (that is, the computer has existing dynamic disks), import the disk, and then take the disk back to the original computer and import it.

How to Move Disks

To move a hard disk from one computer to another, follow this procedure:

  1. Review the preceding limitations to ensure that you can access the data on the disks after you move them.

  2. As a precaution, back up the data on the disk.

  3. Remove the disk from the original computer.

    Although you do not need to turn off the computer to remove an external disk or hot-swappable disk, if the Safely Remove Hardware icon appears in the taskbar notification area, you must use the Safely Remove Hardware application to alert Windows XP that you are removing the disk. If the Safely Remove Hardware icon is not in the notification area, you must use Device Manager to uninstall the disk before you unplug it. However, to move an internal disk, you must turn off and unplug the original computer before you remove the disk. Then turn off and unplug the target computer before you add the disk. For more information about removing external disks, see Chapter 9, “Managing Devices.”

  4. Install the disk in a computer that is running Windows XP Professional.

  5. Log on to Windows XP Professional as a member of the Administrators group, and then open Disk Management.

  6. On the Action menu, click Rescan Disks. If the disk does not appear in Disk Management, open Device Manager, and then from the Action menu click Scan for hardware changes.

All newly attached disks appear in the Disk Management snap-in, but only basic disks are immediately accessible. If the disks you moved were dynamic disks, they appear as Foreign disks and you must import them before you can access data on them. For more information, see “Importing Foreign Disks” later in this chapter.

Basic volumes are assigned the next available drive letter, which might differ from the drive letter used by the previous operating system. For more information about how Windows XP Professional assigns drive letters, see the Microsoft Knowledge Base link on the Web Resources page at http://www.microsoft.com/windows/reskits/webresources. Search the Knowledge Base by using the keywords “LDM” and “cmdcons”.

Removing Disks from the Dynamic Disk Database

After you remove a dynamic disk from a computer, the remaining online dynamic disks retain information about the removed disk and its volumes in the dynamic disk database. As a result, Disk Management still displays the removed hard disk but shows it as Offline and assigns it the status of Missing.

You can delete all references to the removed disk by updating the dynamic disk database. To do this, use Disk Management to remove all volumes on the missing disk. After you remove all the volumes, right-click the missing disk, and then click Remove Disk. The missing disk is no longer displayed in Disk Management.

You need at least one online dynamic disk to retain information about missing disks and their volumes. When you remove the last dynamic disk, you lose the information, and the missing disks are no longer displayed in Disk Management.

For more information about disk and volume error conditions, see Chapter 28, “Troubleshooting Disks and File Systems.”

Importing Foreign Disks

If you move one or more dynamic disks from a disk group to another computer that has its own disk group, the dynamic disks you moved are marked as Foreign until you import the disks into the existing disk group. You must import the disks before you can access volumes on the disk.

In computers that are running any combination of Windows 2000 and Windows XP Professional, you do not need to import existing dynamic disks because the disks are imported automatically each time you start either operating system.

You cannot import dynamic disks into computers running Windows XP Home Edition because it cannot read dynamic disks.

To import disks
  1. In Disk Management, right-click any disk that is marked as Foreign, and then click Import Foreign Disks.

  2. Select the disk group that you want to import.

    Even if multiple disk groups are present, you must import one group at a time. If you want to view the disks that are part of a disk group, select the disk group, and then click the Disks button.

  3. Carefully review the information in the Foreign Disk Volumes dialog box to ensure that you can access the volumes after you import the disks.

As Figure 12-3 shows, the Foreign Disk Volumes dialog box describes what will happen to each volume after you import the disks. If a volume condition shows as OK, you can access the volume after you import the disks. However, if a volume condition shows as Data incomplete, you must import the remaining disks that contain the multidisk volume before you can access the volume.

Figure 12-3 Foreign Disk Volumes dialog box

Figure 12-3 Foreign Disk Volumes dialog box

Because spanned and striped volumes span multiple disks, the status of a multidisk volume can become complicated if you do not move all the disks at the same time. Another complication can arise when you move a disk and then later move additional disks. Although you can move volumes incrementally, the procedure can be complicated and is therefore not recommended. For this reason, when you move volumes that span multiple disks, you need to move them all at the same time.

The following sections describe the volume states that occur when you move the specified volume types.

Importing Spanned or Striped Volumes

You can import spanned or striped volumes into computers running Windows XP Professional, Windows XP Professional x64 Edition, or any edition of Windows 2000 or Windows Server 2003.

Whenever possible, move all disks that contain spanned or striped volumes at the same time. Moving the disks at the same time ensures that the volumes have the Healthy status after import. If you move only some disks from one system to another, the volume becomes disabled during import and also becomes disabled on the original system. As long as you do not delete the volume on either the original or the target system, you can move the remaining disks later. When you move all disks over to the other system, the volume returns its original state.

Importing Mirrored or RAID-5 Volumes

Do not import mirrored or RAID-5 volumes into computers running Windows XP Professional or Windows 2000 Professional. Because these operating systems do not support mirrored or RAID-5 volumes, you cannot access data on these volumes after the import. You must move the volume back to a computer running Windows 2000 Server or Windows Server 2003 to access the volume.

Drive Letter Assignments for Imported Dynamic Volumes

Because dynamic disks store drive letter information in the dynamic disk database, imported volumes use their existing drive letters unless those drive letters are already used. If the previous drive letter is unavailable, Disk Management assigns the next available drive letter to the imported volume.

For more information about how Windows XP Professional assigns drive letters, see the Microsoft Knowledge Base link on the Web Resources page at http://www.microsoft.com/windows/reskits/webresources. Search the Knowledge Base by using the keywords “LDM” and “cmdcons”.

For more information about disk groups and importing disks, see article 222189, “Description of Disk Groups in Windows 2000 Disk Management,” in the Microsoft Knowledge Base. To find this article, see the Microsoft Knowledge Base link on the Web Resources page at http://www.microsoft.com/windows/reskits/webresources.

Managing GPT Disks in 64-Bit Computers

In 64-bit computers running Windows XP Professional x64 Edition, the BIOS is still used to boot, and only master boot record (MBR) disks can be used as boot disks. However, GPT disks can be used as data disks and offer some advantages over MBR disks as Table 12-4 illustrates.

Table 12-4 Comparison of MBR and GPT Disks

Characteristic

MBR Disk

GPT Disk

Number of partitions on basic disks

Supports up to either:

  • Four primary partitions per disk, or

  • Three primary partitions and an extended partition with unlimited logical drives.

Supports up to 128 partitions.

Compatible operating systems

Can be read by:

  • Microsoft MS-DOS

  • Microsoft Windows 95

  • Microsoft Windows 98

  • Microsoft Windows Me

  • Windows NT, all versions

  • Windows 2000, all versions

  • Windows XP

Can be read by Windows XP Professional x64 Edition and Windows Server 2003 Service Pack 1.

Maximum size of basic volumes

Supports basic volumes up to 2 terabytes.

Supports basic volumes up to 18 exabytes.

Maximum size of dynamic volumes

Supports the maximum volume size of the file system used to format the volume.

Supports the maximum volume size of the file system used to format the volume.

Partition tables (copies)

Contains one copy of the partition table.

Contains primary and backup partition tables for redundancy and checksum fields for improved partition structure integrity.

Locations for data storage

Stores data in partitions and in unpartitioned space. Although most data is stored within partitions, some data might be stored in hidden or unpartitioned sectors created by OEMs or other operating systems.

Stores user and program data in partitions that are visible to the user. Stores data that is critical to disk operation in partitions that are not visible to the user. Does not store data in unpartitioned space.

Troubleshooting methods

Uses the same methods and tools that you use in Windows 2000.

Uses tools designed for GPT disks. (Do not use MBR troubleshooting tools on GPT disks.)

By default, Windows XP Professional x64 Edition initializes new disks on 64-bit computers as MBR disks. You can have both GPT and MBR disks on a 64-bit computer, but you must have at least one MBR disk that has a primary partition or simple volume that contains Windows XP Professional x64 Edition. For more information about the required GPT partitions, see “Required Partitions on GPT Disks” in this chapter.

You can convert a disk from GPT to MBR or vice versa as long as the disk is empty.

To change the partition style of an empty disk

  • Right-click the disk, and then click Convert to GPT Disk or Convert to MBR Disk.

You can configure GPT disks and MBR disks as basic or dynamic. You can perform the same tasks on GPT disks that you perform on MBR disks with the following exceptions:

  • You can use the Disk Management snap-in to format partitions on GPT disks by using NTFS. If you want to format GPT disks by using FAT or FAT32, you must use the format command at the command prompt.

  • You cannot use GPT on the following:

    • Removable media

    • Detachable disks that use universal serial bus (USB) or IEEE 1394 (also called FireWire) interfaces

    • Cluster disks that connect to shared SCSI or Fibre channel buses used by Cluster service

Required Partitions on GPT Disks

Windows XP Professional x64 Edition creates special partitions on GPT disks to store private system data, such as the dynamic disk database. On MBR disks, this system data is often stored in unused regions of the disk. However, GPT disks do not support the storing of data in unused space, so Windows XP Professional x64 Edition creates the partitions required to store private system data when you initialize a GPT disk.

The partitions on a GPT disk vary depending on whether the disk is basic or dynamic. Table 12-5 describes the required partitions on basic and dynamic GPT disks.

Table 12-5 Required Partitions on Basic and Dynamic GPT Disks

Partition Type

Basic GPT Disks

Dynamic GPT Disks

Microsoft Reserved (MSR) partition

X

X

Primary partition

X

 

Logical Disk Manager (LDM) Metadata partition

 

X

LDM Data partition

 

X

A basic GPT disk might not contain primary partitions. For example, when you install a new disk and configure it as a GPT disk, Windows XP Professional x64 Edition automatically creates the Microsoft Reserved (MSR) partition but does not create primary partitions. You must create one or more primary partitions before you can store data on a basic GPT disk.

Microsoft Reserved Partition

The Microsoft Reserved (MSR) partition is required on every GPT disk. Windows XP Professional x64 Edition reserves the space in the MSR so that system components are guaranteed space to allocate new partitions for their own use. For example, when you convert a basic GPT disk to dynamic, the system removes 1 MB of the MSR partition and uses that space to create the LDM Metadata partition.

The size of the MSR partition varies. For GPT disks that are smaller than 16 gigabytes (GB), it is 32 MB. For disks larger than 16 GB, the MSR partition is 128 MB.

Windows XP Professional x64 Edition creates an MSR partition in the following situations:

  • The Disk Management snap-in and DiskPart create an MSR partition on any disk that is converted from MBR to GPT.

  • The Disk Management snap-in and DiskPart create an MSR partition on any GPT disk that does not contain an MSR partition. Windows XP Professional x64 Edition usually places the MSR partition at the beginning of the disk. However, if primary partitions exist at the beginning of the disk, the MSR is placed at the end of the disk.

    Note The MSR partition is not shown in Disk Management and does not receive a drive letter.

Primary Partition

You create primary partitions on basic disks to store data. Every primary partition you create appears in the GUID partition entry array (similar to the partition table in MBR disks). The GUID partition entry array supports up to 128 partitions, including primary partitions and other required partitions. For example, if a GPT contains a Microsoft Reserved partition, you can create an additional 127 primary partitions. For more information about the GUID partition entry array, see Chapter 28, “Troubleshooting Disks and File Systems.”

If you convert a basic disk that contains primary partitions to dynamic, the primary partitions become simple volumes, and information about them is stored in the dynamic disk database, not in the GUID partition entry array.

LDM Data Partition

Windows XP Professional x64 Edition creates LDM Data partitions during the conversion to dynamic disk. LDM Data partitions act as containers for dynamic volumes, allocating the disk for use by the dynamic disk database.

Remote Disk and Command-Line Disk Management

You can manage remote computers that are running Windows XP Professional, Windows XP Professional x64 Edition, Windows 2000, or Windows Server 2003 by using the Disk Management snap-in. After you select the remote computer you want to manage, you can remotely perform the same tasks that you normally perform while sitting at the remote computer.

By using the DiskPart command-line tool, you can create scripts to automate disk-related tasks, such as creating volumes or converting disks to dynamic. Scripting these tasks is useful if you are deploying Windows XP Professional by using Unattended Installation or the System Preparation (Sysprep) tool, which does not support creating volumes other than the boot volume.

Note Sysprep.exe is part of Deploy.cab, which is located in the \Support\Tools folder on the Windows XP Professional operating system CD.

Managing Disks on Remote Computers

You can use Disk Management to manage disks on remote computers that run Windows XP Professional, Windows XP Professional x64 Edition, Windows 2000, or Windows Server 2003. You must be a member of the Administrators group on both the local and remote computers, and the computers must be within the same domain or within trusted domains.

When managing disks and volumes on remote computers, you can:

  • Use a computer that is running Windows XP Professional or Windows XP Professional x64 Edition to manage disks on a remote computer that is running Windows 2000 or Windows Server 2003 and vice versa.

  • Use an x86-based computer to manage a 64-bit computer and vice versa.

The types of volumes and disks you can create depend on the operating system that you are running on the remote computer, not the local computer. For example, only the Windows 2000 Server and Windows Server 2003 families support mirrored volumes and RAID-5 volumes. Therefore, you can use a computer running Windows XP Professional to create mirrored or RAID-5 volumes on a remote computer running Windows 2000 Server or Windows Server 2003. See Table 12-3 earlier in this chapter for more information about the types of volumes and disks available on each edition of Windows XP Professional, Windows 2000 Server, and Windows Server 2003.

To manage disks on a remote computer
  1. Click Start, and then click Run.

  2. In the Open box, type compmgmt.msc and then click OK.

  3. In the Computer Management snap-in, right-click Computer Management (Local) and then click Connect to another computer.

  4. In Another Computer, type the name of the computer that you want to connect to remotely.

When you manage disks in a remote computer, the following limitations apply:

  • If you use a computer that is running Windows 2000 to manage a remote 64-bit computer that is running Windows XP Professional x64 Edition, you cannot manage dynamic disks in the remote computer if one of the disks in the disk group is a GPT disk.

  • If you use a computer that is running Windows XP Professional to manage a remote computer that is running Windows 2000, the property page for IEEE 1394 and USB detachable disks does not show all information.

Managing Disks from the Command Line by Using DiskPart

DiskPart.exe is a text-mode command interpreter that is separate from the Windows XP Professional command prompt. DiskPart allows you to manage fixed (nonremovable) disks and volumes by using scripts or direct input.

To run DiskPart, at the command prompt, type diskpart.

To view a list of DiskPart commands, at the DiskPart command prompt, type commands.

For more information about using the DiskPart commands, see Windows XP Professional Help.

Creating DiskPart Scripts

You can create DiskPart scripts in text files by using any extension. To run a DiskPart script from the command line, type:

diskpart /s testscript.txt

To create a log file of the DiskPart session, type:

diskpart /s testscript.txt > logfile.txt

DiskPart does not have a format command. You must run the format command from the command prompt either manually or by using a batch file. The following example shows a batch file called Formatpart.bat and a DiskPart script called Createpart.txt. The batch file executes the DiskPart script and then runs the format command.

In Formatpart.bat:

diskpart /s createpart.txt 
format g: /fs:ntfs

In Createpart.txt:

select disk 1 
create volume simple size 4096 
assign letter g
When to Use DiskPart Scripting

A common scenario for using DiskPart scripts is when you deploy Windows XP Professional by using Unattended Installation or Sysprep:

  • Unattended Installation.

    A hands-free method of installing Windows XP Professional that is convenient for system administrators, original equipment manufacturers (OEMs), value-added resellers (VARs), and other users who install Windows XP Professional on many computers or who frequently install Windows XP Professional on the same computer.

  • System Preparation (Sysprep) Tool.

    A simple utility that you can use together with third-party disk imaging utilities to prepare a system that you want to duplicate. Sysprep uses an answer file to automate Mini-Setup, which shortens the graphical user interface (GUI) setup mode. In GUI setup mode, the end user is prompted only for required and user-specific information, such as accepting the Microsoft End-User License Agreement (EULA), entering the Product Key, and adding user and company names.

You can create additional volumes or perform other disk-related tasks when you use Unattended Installation or Sysprep by using answer files to run DiskPart scripts. An answer file contains answers to questions that Windows XP Professional Setup asks during installation; the answer file automates the responses so that Setup runs without user intervention. It consists of section headers, parameters, and the values for each parameter. The answer file for Unattended Installation is called Unattend.txt, and the answer file for Sysprep is called Sysprep.inf.

For more information about using Unattended Installation and Sysprep, see Chapter 2, “Automating and Customizing Installations.”

Creating partitions by using DiskPart scripts in the [GuiRunOnce] section of Unattend.txt or Sysprep.inf

Table 12-6 describes a scenario in which you create and format two primary partitions by using a batch file called Formatpart.bat. The batch file executes a DiskPart script called Createpart.txt to create the partitions, and then the batch file formats the partitions by using the format command.

Table 12-6 DiskPart Scenario Using [GuiRunOnce]

Scenario

Sample Script

Disk 0: 20 GB basic disk

C: 4 GB NTFS system volume (already created)

D: 16 GB NTFS data volume (uses the remaining unallocated space on the disk)

Disk 1: 60 GB basic disk

R: 60 GB NTFS data volume (uses all unallocated space on the disk)

In Createpart.txt*:

select disk 0 create partition primary assign letter d select disk 1 create partition primary assign letter r

In Formatpart.bat:

diskpart/s createpart.txt echo y | format
d: /fs:ntfs echo y | format r: /fs:ntfs

* You do not need to specify the DiskPart size= parameter in this example because the partitions use all the unallocated space on their respective disks.

You can use Windows Setup Manager to specify Formatpart.bat by following the example shown in Figure 12-4. Programs that you enter in the Command to run box appear in the [GuiRunOnce] section of Unattend.txt or Sysprep.inf.

Figure 12-4 Configuring Run Once in Windows Setup Manager

Figure 12-4 Configuring Run Once in Windows Setup Manager

[GuiRunOnce] contains a list of commands that Windows XP Professional executes the first time a user logs on to the computer after GUI-mode Setup has completed. Each line specifies a command to be executed by the GuiRunOnce registry entry. For example:

[GuiRunOnce] 
Command0 = c:\formatpart.bat

Note For each command line that contains spaces, be sure to place the command in quotation marks when you add the command to the answer file. If you use Windows Setup Manager to specify a command, Windows Setup Manager automatically adds the quotation marks to the answer file.

Commands run by using the GuiRunOnce key run in the security context of the user who is currently logged on. If the user does not have the permissions necessary to run the command completely, the command fails.

Converting disks to dynamic by using DiskPart scripts in the [GuiRunOnce] section of Unattend.txt or Sysprep.inf

Table 12-7 describes a scenario in which you execute a DiskPart script called Convertdyn.txt in the [GuiRunOnce] section of Sysprep.inf. The Convertdyn.txt script converts Disk 0 to dynamic.

Table 12-7 DiskPart Scenario Using Cmdlines.txt

Scenario

Sample Script

Disk 0: 24-GB basic disk to be converted to dynamic

C: 4-GB NTFS system volume (already created)

D: 20-GB NTFS data volume (already created)

In Convertdyn.txt:

Select disk 0 convert dynamic

After the conversion, both basic volumes become dynamic simple volumes. If you need to increase the size of volume D, you can extend the volume to another disk to create a spanned volume.

Most third-party imaging tools are not compatible with dynamic disks. Therefore, you must convert the disk to dynamic after you create the images, and then deploy the images to target computers. Perform the following steps to complete this scenario:

  1. Use Windows Setup Manager to create the Sysprep.inf file or modify an existing file.

  2. Prepare the system for imaging by using Sysprep. Both basic volumes can be present when you create the image, but the disk must be a basic disk.

  3. Clone the image by using a third-party imaging tool.

  4. Download the image to the target systems.

  5. Use Sysprep.inf to execute the DiskPart script that converts Disk 0 to dynamic.

    You are prompted to restart the computer twice to complete the conversion because the disk contains the system volume. For more information about converting the system volume to dynamic, see “Converting Basic Disks to Dynamic Disks” earlier in this chapter.

    Tip For more information on using DiskPart, see article 300415, “A Description of the DiskPart Command-Line Utility,” in the Microsoft Knowledge Base at http://support.microsoft.com.

Managing Disks from the Command Line by Using Fsutil

You can use the Fsutil.exe command-line tool from the command prompt to perform many disk and volume-related tasks on NTFS volumes. Table 12-8 summarizes many of the Fsutil commands related to disks and volumes. For more information about using Fsutil, including the commands not listed here, see Windows XP Professional Help.

Table 12-8 Fsutil Commands Related to Disks and Volumes

Command

Description

fsutil fsinfo drives

Lists the drive letters for all volumes on the computer.

fsutil fsinfo drivetype

Displays the drive type for the specified drive. For example, this command can return Fixed Drive, CD-ROM Drive, and Removable Drive.

fsutil fsinfo volumeinfo

For a specified NTFS volume, displays information about the file system, such as volume name, serial number, and whether the volume supports NTFS-related features, such as disk quotas, encryption, and compression.

fsutil fsinfo statistics

Displays statistics about the specified NTFS volume.

fsutil fsinfo ntfsinfo

Displays information about the specified NTFS volume, such as the total clusters, free clusters, bytes per sector, bytes per cluster, and information about the master file table (MFT).

fsutil volume dismount

Dismounts the specified volume.

fsutil volume diskfree

Displays the total number of bytes in the volume, the number of free bytes, and the number of bytes available for data storage.

Guidelines for Maintaining Disks and Volumes

Table 12-9 describes the guidelines for maintaining disks and volumes as well as the frequency and benefits of performing each task. By following these guidelines as part of a regular maintenance program, you can minimize the chances of excessive downtime or data loss as a result of disk or file system errors.

Table 12-9 Disk and File System Maintenance Guidelines

Guideline

Frequency

Result

Run Disk Defragmenter.

Weekly (during idle times) or as needed

Defragmenting volumes increases file system performance.

For more information about using Disk Defragmenter, see Chapter 28, “Troubleshooting Disks and File Systems.”

Back up data.

Daily

Backing up data prevents data loss caused by hard disk failures, power outages, virus infection, and many other possible computer problems.

For more information about backing up files, see Chapter 14, “Backing Up and Restoring Data.”

Perform a trial restoration to ensure the integrity of your backups.

Monthly

A trial restoration confirms that your files are properly backed up and can uncover hardware problems that do not show up with software verifications.

Review Event Viewer logs.

Daily

Careful monitoring of logs in Event Viewer can help you predict and identify the sources of system problems. For example, if log warnings show that a disk driver can read or write to a sector only after several retries, the sector is likely to go bad.

For more information about using Event Viewer, see Windows XP Professional Help.

Use the Chkntfs command to determine whether volumes are flagged as dirty.

Daily

Running Chkntfs can help you identify volumes that have file system errors. If a volume is flagged as dirty, Windows XP Professional runs Chkdsk when the computer is restarted. You can, however, run Chkdsk immediately or postpone Chkdsk by using the Chkntfs command, although it is recommended that you run Chkdsk as soon as possible. To assess the damage without repairing the volume, you can run Chkdsk in read-only mode.

For more information about using Chkdsk and Chkntfs, see Chapter 28, “Troubleshooting Disks and File Systems.”

Additional Resources

These resources contain additional information and tools related to this chapter.

Related Information

  • Chapter 13, “Working with File Systems”

  • Chapter 28, “Troubleshooting Disks and File Systems,” for more information about troubleshooting problems related to disks and using Chkdsk and Disk Defragmenter

  • Chapter 29, “Troubleshooting the Startup Process,” for more information about the startup process and Boot.ini

  • Chapter 9, “Managing Devices,” for more information about the Device Manager snap-in and disconnecting Plug and Play storage devices

  • Inside Microsoft Windows 2000, Third Edition by David A. Solomon and Mark E. Russinovich, 2000, Redmond: Microsoft Press.

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