Dynamic Volumes Are Not Displayed Accurately in Text-Mode Setup or Recovery Console (227364)


The information in this article applies to:

  • Microsoft Windows 2000 Server
  • Microsoft Windows 2000 Advanced Server
  • Microsoft Windows 2000 Professional
  • Microsoft Windows 2000 Datacenter Server
This article was previously published under Q227364

SYMPTOMS

While you are using the Recovery console to repair an unbootable Windows 2000 system, or during the text-mode portion of Windows 2000 Setup, dynamic disks may not display accurate information about the correct sizes or the complete list of volumes contained on the dynamic disk(s). There is also no visible designation as to whether a disk is a basic or dynamic disk.

NOTE: Deleting or reformatting any dynamic disk volume using the Recovery console's DISKPART or FORMAT command, or during Windows 2000 text-mode Setup, could result in permanent data loss.

CAUSE

Windows 2000 does not fully support pure dynamic disk volumes during Setup. Setup only understands dynamic disk partitions that are hard-linked. Hard-linked dynamic partitions are created when you upgrade a basic disk to dynamic and the basic disk had pre-existing primary and/or logical drives configured. Each of the pre-existing partitions retains a legacy-style partition table entry (type 42 for primary and type 05 for extended), even after upgrading the disk to dynamic. These special hard-linked partition table entries allows Setup to recognize them as valid partitions for installation.

Pure dynamic disks (those not containing any hard-linked partitions) have only a single partition table entry (type 42) to define the entire disk. Dynamic disks store their volume configuration in a database located in a 1-MB private region at the end of each dynamic disk. Volumes contained on a pure dynamic disk are soft-linked, and drive letters for them are not displayed until Setup is complete. Setup displays a single drive letter for the whole drive (usually the drive letter assigned to the first soft-linked partition) even if it has multiple volumes configured. You cannot install a fresh installation to this type of dynamic disk without destroying underlying volumes.

RESOLUTION

Keep a record of all dynamic disks and the volumes they contain, noting which volumes are hard-linked. Uniquely name your volumes so they can be identified during a repair operation or during text-mode Setup. Do not delete any of the dynamic volumes unless you are going to delete all of them from text-mode Setup.

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

MORE INFORMATION

The following examples demonstrate some of the misleading information you may see in text-mode Setup when you have existing dynamic volumes:
  • Dynamic disk with multiple dynamic volumes created after the disk is upgraded from basic:

    Only the first volume is displayed. Its size equals the full size of the disk it is on. Deleting that single volume deletes all dynamic volumes on the disk.
  • System/boot disk is dynamic:

    The system and/or boot volume is displayed as the correct size, but deleting or reinstalling to any volume on this disk may cause the disk to be "dynamic unreadable."
  • Dynamic disk with one volume created before upgrading to dynamic and additional volumes created after the upgrade:

    The first volume appears in text-mode Setup with the correct size. A second volume is displayed as using the rest of the disk, although it may not be that large. Any additional dynamic volumes are not displayed and can be unknowingly removed if the second volume is deleted. Any volumes deleted from any dynamic disk may result in data loss in other volumes.
  • Member of a dynamic mirrored, striped, spanned, or RAID-5 volume:

    These volumes may have the same drive letter as the other members of the volume but are not designated as being a member of one of these types of volumes. Deleting one member may make the other members unusable, depending on the type of volume. The individual members are displayed in the same way as described in the first three examples.
NOTE: The only dynamic volumes on which Windows 2000 can be installed are those that are created on basic disks before the disk is upgraded to dynamic. It is difficult to identify those volumes in text-mode Setup. You should note which volumes were created this way before reinstalling. Volumes that do not span the entire disk are usually the volumes that were created on basic disks and retain their hard-link partitions (partitions that have valid entries in the master boot record [MBR] partition table).

For additional information about how Windows 2000 displays and assigns drive letters during Setup, please see the following article in the Microsoft Knowledge Base:

234048 How Windows 2000 Assigns, Reserves, and Stores Drive Letters

Modification Type:MajorLast Reviewed:11/21/2003
Keywords:kbDiskMemory kbenv kbprb kbsetup KB227364
©2003 Microsoft Corporation. All rights reserved.