Terms

To help you understand the differences between basic disk and dynamic disk, a set of definitions are provided.

Basic Disk

A basic disk is a physical disk that contains primary partitions and/or extended partitions with logical drives used by Windows 2000 and all versions of Windows NT. Basic disks can also contain volume, striped, mirror, or redundant array of independent disks (RAID) Level 5 (also known as striped with parity) sets that were created using Windows NT 4.0 or earlier. As long as a compatible file format is used, basic disks can be accessed by Microsoft® MS-DOS®, Microsoft® Windows® 95, Microsoft® Windows® 98, and all versions of Windows NT.

Since Windows 2000 automatically initializes disks as basic, you can troubleshoot partitions and volumes using the same methods as in Windows NT.

Note

FAT32 is new in Windows 2000. Disk troubleshooting tools from Windows NT will likely not recognize FAT32 boot sectors and may cause problems with FAT32-formatted volumes. If FAT32 is used on your computer, be sure to use a disk troubleshooting tool designed for Windows 2000 that recognizes this file format.

New or empty disks can be initialized as either basic or dynamic after the hardware installation is complete. However, to set up a new fault-tolerant (FT) disk system, you must upgrade to dynamic disk.

Basic Volume

A basic volume is a volume on a basic disk. Basic volumes include primary partitions, logical drives within extended partitions, as well as volume, striped, mirror, or RAID-5 sets created using Windows NT 4.0 or earlier. You cannot create basic volumes on dynamic disks.

Note

Creating new FT sets, such as mirrored and RAID-5 volumes, is only available on computers running Windows 2000 Server. The disk must be upgraded to dynamic disk before these volumes can be created. You can, however, use a computer running Windows 2000 Professional to create mirrored and RAID-5 volumes on a remote computer running Windows 2000 Server.

Dynamic Disk

A dynamic disk is a physical disk that has been upgraded by and is managed with Disk Management. Dynamic disks do not use partitions or logical drives. They can contain only dynamic volumes created by Disk Management. Only computers running Windows 2000 can access dynamic volumes.

Note

Disks that have been upgraded from basic to dynamic disk still contain references to partitions in the partition table of the MBR. However, the MBR's reference to these partitions identifies the partition types as dynamic, indicating to Windows 2000 that the disk configuration data is now maintained in the disk management database at the end of the disk. Furthermore, any new changes made to the disk, such as deleting existing or creating additional volumes, are not recorded in the partition table.

Dynamic disks use dynamic volumes to subdivide physical disks into one or more drives enumerated by letters of the alphabet. Disk configuration data is contained in a disk management database stored in the last 1 megabyte (MB) of space at the end of the disk. Since dynamic disks do not use the traditional disk organization scheme of partitions and logical volumes, they cannot be directly accessed by MS-DOS, Windows 95, Windows 98, or any versions of Windows NT. Disk shares on dynamic disks, however, are available to computers running all of these operating systems.

Dynamic Volume

A dynamic volume is a logical volume that is created on a dynamic disk using Disk Management. Dynamic volume types include simple, spanned, striped, mirrored, and RAID-5, although only Windows 2000 Server supports the FT volume types (mirrored and RAID-5). You cannot create dynamic volumes on basic disks. Dynamic volumes are not supported on portable computers or removable media.

Note

Dynamic volumes that were upgraded from basic disk partitions cannot be extended. This specifically includes the system volume, which contains hardware-specific files needed to start Windows 2000, and the boot volume, which contains the Windows 2000 system files required for startup. Only volumes created after the disk was upgraded to dynamic can be extended.

Partitions and Volumes

When you upgrade to dynamic disk, existing partitions and logical volumes are converted into dynamic volumes. Table 1.1 illustrates the translation of terms between basic and dynamic disk structures.

Table 1.1 Translation of Terms Between Basic and Dynamic Disk

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