Break a mirrored volume into two volumes

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

To break a mirrored volume into two volumes

  • 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 one of the volume copies in the mirrored volume, and then click Break Mirrored Volume.

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.

  • When you break a mirrored volume, the two volume copies that made up the mirrored volume become two independent simple volumes. These volumes are no longer fault tolerant. One of the volumes retains the drive letter or mount point, while the other volume is assigned the next available drive letter.

Using a command line

  1. Open Command Prompt.

  2. Type:

    diskpart

  3. At the DISKPART prompt, type:

    list volume

    Make note of the number of the mirrored volume.

  4. At the DISKPART prompt, type:

    select volume n

    Select the mirrored volume you want to break into two separate volumes.

  5. At the DISKPART prompt, type:

    detail volume

    Make note of the disk number of the mirrored volume you want to break into two separate volumes.

  6. At the DISKPART prompt, type:

    break disk n

Value Description

list volume

Displays a list of basic and dynamic volumes on all disks.

select volume

Selects the specified volume, where n is the volume number, and gives it focus. If no volume is specified, the select command lists the current volume with focus. You can specify the volume by number, drive letter, or mount point path. On a basic disk, selecting a volume also gives the corresponding partition focus.

detail volume

Displays the disks on which the current volume resides.

break disk n

Applies to dynamic disks only. Breaks a mirrored volume into two simple volumes. These volumes are no longer fault tolerant. The disk specified by n receives the focus so you can assign it a drive letter. If the specified disk is the current system or boot disk, the command fails. The other disk retains the drive letter and any mount points that belonged to the mirrored volume.

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 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

Remove a mirror from a mirrored volume
Working with MMC console files
DiskPart