Change a basic disk into a dynamic disk

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

To change a basic disk into a dynamic disk

• Using the Windows interface

• Using a command line

Using the Windows interface

1. Open Computer Management (Local).

2. In the console tree, click Computer Management (Local), click Storage, and then click Disk Management.

3. Right-click the basic disk you want to convert, click Convert to Dynamic Disk, and then follow the instructions on your screen.

   If you do not see this menu item, you might be right-clicking a volume instead of a disk, the disk might have been previously converted to a dynamic disk, or the computer is a portable computer. (Dynamic disks are not supported on portable computers, removable disks, detachable disks that use Universal Serial Bus (USB) or IEEE 1394 (also called FireWire) interfaces, or on disks connected to shared SCSI buses.) In addition, you cannot convert cluster disks connected to shared SCSI or Fibre Channel buses to dynamic. The Cluster service supports basic disks only.)

Caution

• If you are using a basic disk as a storage area for shadow copies and you intend to convert the disk into a dynamic disk, it is important to take the following precaution to avoid data loss. If the disk is a non-boot volume and is a different volume from where the original files reside, you must first dismount and take offline the volume containing the original files before you convert the disk containing shadow copies to a dynamic disk. You must bring the volume containing the original files back online within 20 minutes, otherwise, you will lose the data stored in the existing shadow copies. If the shadow copies are located on a boot volume, you can convert the disk to dynamic without losing shadow copies.

  You can use the mountvol command with the /p option to dismount the volume and take it offline. You can mount the volume and bring it online using the mountvol command or the Disk Management snap-in.

Notes

• To perform this procedure on a local computer, you must be a member of the Backup Operators group or Administrators group on the local computer, or you must have been delegated the appropriate authority. To perform this procedure remotely, you must be a member of the Backup Operators group or Administrators group on the remote computer. If the computer is joined to a domain, members of the Domain Admins group might be able to perform this procedure. As a security best practice, consider using Run as to perform this procedure. For more information, see Default local groups, Default groups, and Using Run as.

• To open Computer Management, click Start, click Control Panel, double-click Administrative Tools, and then double-click Computer Management.

• For additional information about converting basic disks to dynamic disks, see Related Topics.

• After you convert a basic disk to a dynamic disk, you cannot change the dynamic volumes back to partitions. Instead, you must delete all dynamic volumes on the disk and then use the Convert To Basic Disk command. If you want to keep your data, you must first back it up or move it to another volume. For more information about the Convert To Basic Disk command, see Related Topics.

• Before you convert disks, close any programs that are running on those disks.

• Once converted, a dynamic disk will not contain basic volumes (primary partitions or logical drives), nor can it be accessed by MS-DOS, Windows 95, Windows 98, Windows Millennium Edition, Windows NT, or Windows XP Home Edition operating systems. Dynamic disks can only be accessed with Windows 2000, Windows XP Professional, or Windows Server 2003 operating systems.

• When you convert a basic disk to a dynamic disk, any existing partitions or logical drives on the basic disk become simple volumes on the dynamic disk.

• Do not convert disks to dynamic that contain multiple installations of Windows 2000, Windows XP Professional, or Windows Server 2003 operating systems. It is likely that you will no longer be able to start the second installation.

• For the conversion to succeed, any master boot record (MBR) disks to be converted must contain at least 1 MB of space for the dynamic disk database. Windows 2000, Windows XP Professional, and Windows Server 2003 operating systems, automatically reserves this space when creating partitions or volumes on a disk, but disks with partitions or volumes created by other operating systems may not have this space available. (This space may exist even if it is not visible in Disk Management.)

Using a command line

1. Open Command prompt.

2. Type:

   diskpart

3. At the DISKPART prompt, type:

   list disk

   Make note of the disk number of the disk you want to convert to dynamic.

4. At the DISKPART prompt, type:

   select diskn

5. At the DISKPART prompt, type:

   convert dynamic

Value	Description
list disk	Displays a list of disks and information about them, such as their size, amount of available free space, whether the disk is a basic or dynamic disk, and whether the disk uses the master boot record (MBR) or GUID partition table (GPT) partition style. The disk marked with an asterisk (*) has focus.
select disk	Selects the specified disk, where n is the disk number, and gives it focus.
convert dynamic	Converts a basic disk into a dynamic disk. Any existing partitions on the disk become simple volumes.

Caution

• If you are using a basic disk as a storage area for shadow copies and you intend to convert the disk into a dynamic disk, it is important to take the following precaution to avoid data loss. If the disk is a non-boot volume and is a different volume from where the original files reside, you must first dismount and take offline the volume containing the original files before you convert the disk containing shadow copies to a dynamic disk. You must bring the volume containing the original files back online within 20 minutes, otherwise, you will lose the data stored in the existing shadow copies. If the shadow copies are located on a boot volume, you can convert the disk to dynamic without losing shadow copies.

  You can use the mountvol command with the /p option to dismount the volume and take it offline. You can mount the volume and bring it online using the mountvol command or the Disk Management snap-in.

Notes

• To perform this procedure on a local computer, you must be a member of the Backup Operators group, Administrators group, or you must have been delegated the appropriate authority. If the computer is joined to a domain, members of the Domain Admins group might be able to perform this procedure. As a security best practice, consider using Run as to perform this procedure. For more information, see Default local groups, Default groups, and Using Run as.

• To open a command prompt, click Start, point to All programs, point to Accessories, and then click Command prompt.

• For additional information about converting basic disks to dynamic disks, see Related Topics.

• After you convert a basic disk to a dynamic disk, you cannot change the dynamic volumes back to partitions. Instead, you must delete all dynamic volumes on the disk and then use the DiskPart convert basic command. If you want to keep your data, you must first back it up or move it to another volume. For more information about DiskPart, see Related Topics.

• Before you convert disks, close any programs that are running on those disks.

• Once converted, a dynamic disk will not contain partitions or logical drives, nor can it be accessed by MS-DOS, Windows 95, Windows 98, Windows Millennium Edition, Windows NT, or Windows XP Home Edition operating systems. Dynamic disks can be accessed only with Windows 2000, Windows XP Professional, or Windows Server 2003 operating systems.

• When you convert a basic disk to a dynamic disk, any existing partitions or logical drives on the basic disk become simple volumes on the dynamic disk.

• Do not convert disks to dynamic that contain multiple installations of Windows 2000, Windows XP Professional, or Windows Server 2003 operating systems. It is likely that you will no longer be able to start the second installation.

• For the conversion to succeed, any master boot record (MBR) disks to be converted must contain at least 1 MB of space for the dynamic disk database. Windows 2000, Windows XP Professional, and Windows Server 2003 operating systems, automatically reserves this space when creating partitions or volumes on a disk, but disks with partitions or volumes created by other operating systems may not have this space available. (This space may exist even if it is not visible in Disk Management.)

• For more information about DiskPart, see Related Topics.

Information about functional differences

• Your server might function differently based on the version and edition of the operating system that is installed, your account permissions, and your menu settings. For more information, see Viewing Help on the Web.

See Also

Concepts

Converting a basic disk to dynamic
Change a dynamic disk back to a basic disk
Support for removable media
Partition styles
Working with MMC console files
Dynamic disks and volumes
DiskPart