Disks and Volumes

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

Disks and Volumes

The Microsoft Windows Server 2003 operating system offers two types of disks for storing information on your server: basic and dynamic. Basic and dynamic disks offer flexibility in the types of volumes you use to store data. In x86-based computers, basic disks are the default type of storage and use the same disk structures as those used by the Microsoft MS-DOS operating system and all previous versions of Microsoft Windows. Dynamic disks provide features that basic disks do not, such as the ability to create volumes that span multiple disks, including fault-tolerant volumes. Dynamic disks were introduced in Microsoft Windows 2000, and use a database to track information about dynamic volumes on the disk and about other dynamic disks in the computer. Because each dynamic disk in a computer stores a replica of the dynamic disk database, Windows Server 2003 can repair a corrupted database on one dynamic disk by using the database on another dynamic disk.

When using basic disks in x86-based computers, you are limited to creating four primary partitions per disk, or three primary partitions and one extended partition with unlimited logical drives. Primary partitions and logical drives on basic disks are known as basic volumes. All volumes on dynamic disks are known as dynamic volumes. All dynamic disks in a computer automatically belong to the same disk group.

The term partition style refers to the method that Windows Server 2003 uses to organize partitions on the disk. All x86-based computers use the partition style known as the master boot record (MBR). The MBR contains a partition table that describes where the partitions are located on the disk. Because MBR is the only partition style available on x86-based computers, it is used automatically and you do not need to choose this style.

Itanium-based computers running the 64-bit versions of Windows Server 2003 use a new partition style called the globally unique identifier (GUID) partition table (GPT). The GPT partition style supports partitions up to 2 terabytes and 128 partitions per disk.

Note

• You can use the 64-bit versions of Windows Server 2003 to manage MBR disks and GPT disks. However, you cannot start the 64-bit versions of Windows Server 2003 from an MBR disk.

After you install a new disk, you must choose a partition style and storage type to use on the disk. Your choices vary according to which operating system you are running and whether the computer is an x86-based computer or an Itanium-based computer. The following table lists the storage types and partition styles that are available for each version of Windows Server 2003.

Storage Types and Partition Styles Available in Windows Server 2003

Operating System	Basic Volumes	Dynamic Simple, Spanned, and Striped Volumes	Dynamic Mirrored and RAID-5 Volumes	MBR Partition Style	GPT Partition Style
Windows Server 2003, Standard Edition
Windows Server 2003, Enterprise Edition
Windows Server 2003, Datacenter Edition
Windows Server 2003, Web Edition
The 64-bit version of Windows Server 2003, Enterprise Edition
The 64-bit version of Windows Server 2003, Datacenter Edition

The introduction of GPT makes understanding the partition styles a bit more challenging, but most disk-related tasks are unchanged. You can still use basic disks and dynamic disks as you did in Windows 2000, and these storage types are available on disks that use either partition style.

The Disk Management snap-in differentiates between partition styles by referring to disks that use the master boot record as MBR disks and disks that use the GUID partition table as GPT disks. The following figure shows how Disk Management displays GPT and MBR disks in an Itanium-based computer.

How Disk Management Displays GPT and MBR Disks on an Itanium-based Computer