Difference Between Basic and Dynamic Disks in Windows XP/2000/2003
Microsoft Windows XP, Windows 2000 and Windows Server 2003 offer two types of disk storage: basic and dynamic.
Basic Disk Storage
Basic storage uses normal partition tables supported by MS-DOS, Microsoft Windows 95, Microsoft Windows 98, Microsoft Windows Millennium Edition (Me), Microsoft Windows NT, Microsoft Windows 2000, Windows Server 2003 and Windows XP. A disk initialized for basic storage is called a basic disk. A basic disk contains basic volumes, such as primary partitions, extended partitions, and logical drives. Additionally, basic volumes include multidisk volumes that are created by using Windows NT 4.0 or earlier, such as volume sets, stripe sets, mirror sets, and stripe sets with parity. Windows XP does not support these multidisk basic volumes. Any volume sets, stripe sets, mirror sets, or stripe sets with parity must be backed up and deleted or converted to dynamic disks before you install Windows XP Professional.
Dynamic Disk Storage
Dynamic storage is supported in Windows XP Professional, Windows 2000 and Windows Server 2003. A disk initialized for dynamic storage is called a dynamic disk. A dynamic disk contains dynamic volumes, such as simple volumes, spanned volumes, striped volumes, mirrored volumes, and RAID-5 volumes. With dynamic storage, you can perform disk and volume management without the need to restart Windows.
Note: Dynamic disks are not supported on portable computers or on Windows XP Home Edition-based computers.
You cannot create mirrored volumes or RAID-5 volumes on Windows XP Home Edition, Windows XP Professional, or Windows XP 64-Bit Edition-based computers. However, you can use a Windows XP Professional-based computer to create a mirrored or RAID-5 volume on remote computers that are running Windows 2000 Server, Windows 2000 Advanced Server, or Windows 2000 Datacenter Server, or the Standard, Enterprise and Data Center versions of Windows Server 2003.
Storage types are separate from the file system type. A basic or dynamic disk can contain any combination of FAT16, FAT32, or NTFS partitions or volumes.
A disk system can contain any combination of storage types. However, all volumes on the same disk must use the same storage type.
To convert a Basic Disk to a Dynamic Disk:
Use the Disk Management snap-in in Windows XP/2000/2003 to convert a basic disk to a dynamic disk. To do this, follow these steps:
- Log on as Administrator or as a member of the Administrators group.
- Click Start, and then click Control Panel.
- Click Performance and Maintenance, click Administrative Tools, and then double-click Computer Management. You can also right-click My Computer and choose Manage if you have My Computer displayed on your desktop.
- In the left pane, click Disk Management.
- In the lower-right pane, right-click the basic disk that you want to convert, and then click Convert to Dynamic Disk. You must right-click the gray area that contains the disk title on the left side of the Details pane.
- Select the check box that is next to the disk that you want to convert (if it is not already selected), and then click OK.
- Click Details if you want to view the list of volumes in the disk. Click Convert.
- Click Yes when you are prompted to convert the disk, and then click OK.
Warning: After you convert a basic disk to a dynamic disk, local access to the dynamic disk is limited to Windows XP Professional, Windows 2000 and Windows Server 2003. Additionally, after you convert a basic disk to a dynamic disk, the dynamic volumes cannot be changed back to partitions. You must first delete all dynamic volumes on the disk and then convert the dynamic disk back to a basic disk. If you want to keep your data, you must first back up the data or move it to another volume.
Dynamic Storage Terms
A volume is a storage unit made from free space on one or more disks. It can be formatted with a file system and assigned a drive letter. Volumes on dynamic disks can have any of the following layouts: simple, spanned, mirrored, striped, or RAID-5.
A simple volume uses free space from a single disk. It can be a single region on a disk or consist of multiple, concatenated regions. A simple volume can be extended within the same disk or onto additional disks. If a simple volume is extended across multiple disks, it becomes a spanned volume.
A spanned volume is created from free disk space that is linked together from multiple disks. You can extend a spanned volume onto a maximum of 32 disks. A spanned volume cannot be mirrored and is not fault-tolerant.
A striped volume is a volume whose data is interleaved across two or more physical disks. The data on this type of volume is allocated alternately and evenly to each of the physical disks. A striped volume cannot be mirrored or extended and is not fault-tolerant. Striping is also known as RAID-0.
A mirrored volume is a fault-tolerant volume whose data is duplicated on two physical disks. All of the data on one volume is copied to another disk to provide data redundancy. If one of the disks fails, the data can still be accessed from the remaining disk. A mirrored volume cannot be extended. Mirroring is also known as RAID-1.
A RAID-5 volume is a fault-tolerant volume whose data is striped across an array of three or more disks. Parity (a calculated value that can be used to reconstruct data after a failure) is also striped across the disk array. If a physical disk fails, the portion of the RAID-5 volume that was on that failed disk can be re-created from the remaining data and the parity. A RAID-5 volume cannot be mirrored or extended.
The system volume contains the hardware-specific files that are needed to load Windows (for example, Ntldr, Boot.ini, and Ntdetect.com). The system volume can be, but does not have to be, the same as the boot volume.
The boot volume contains the Windows operating system files that are located in the %Systemroot% and %Systemroot%’System32 folders. The boot volume can be, but does not have to be, the same as the system volume.