Introduction of dynamic disk
We may have heard these terms: basic disk and dynamic disk which are two different storage types of disk. The former one refers to a disk that contains partitions, such as primary/extended/logical partitions, while dynamic disk is a physical disk with features that basic disk does not have. For example, dynamic disk supports creating volumes that cross several disks (spanned and striped volumes) and creating fault-tolerant volumes (mirrored and RAID-5 volumes). Most of us may not be familiar with the volumes mentioned above; please don’t worry, we will give a detailed interpretation in the following paragraphs.
Dynamic disk does not use a Master Boot Record (MBR); it uses a 1 MB hidden database, often known as Logical Disk Manager which is located at the end of the dynamic disk, to records all information about dynamic volumes on the disk.
Dynamic disk was first introduced with Windows 2000, and it is supported in Windows XP Professional and Server 2003 but not all versions. We can refer to the following chart for get detailed information.
|Operating System||Simple, Spanned and Striped Volume||Mirrored Volume||RAID-5 Volume|
|Windows 9x/Me, DOS|
|Windows 2000 Professional|
|Windows 2000 Server|
|Windows 2000 Advanced Server|
|Windows XP Home|
|Windows XP Professional|
|Windows Server 2003 Standard|
|Windows Server 2003 Enterprise|
|Windows Vista Ultimate|
|Windows 2008 Server|
|Windows 2008 Web Server|
|Windows 7/8 Ultimate|
Types of dynamic volumes
Simple volumes just like the primary or logical partition of basic disk. If there is only one dynamic disk, we can only create simple volume. 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.
Spanned volumes consist of at lease two dynamic disks. The areas of unallocated space used to create spanned volumes can be different sizes. Spanned volumes are organized sequentially and are not fault tolerant. It also can be extended and mirrored. After a partition is extended, no portion of it can be deleted without deleting the entire spanned volumes.
Striped volumes are composed of free space on two more disks, which is similar to spanned volumes. However, the difference is that stripped volumes can improve the writing and reading speed of data by adding data to all disks at the same time. A striped volume cannot be mirrored or extended and is not fault tolerant.
Mirrored volumes are also known as RAID 1. A mirrored volume is a fault-tolerant partition that stores an exact copy of data from another disk. Mirrored volumes need two disks; if one disk fails another can be unaffected and work normally.
RAID-5 volumes require three disks at least. RAID-5 is a combination of striped and mirrored volume. It is fault tolerant and has a high writing and reading speed of data. RAID-5 volumes are available only on computers running server operating systems.
From the introduction above, we may have a general understanding about dynamic disk and the dynamic volume. With a dynamic disk we can perform disk and partition management without restarting computer. If you want to manage your dynamic disk and dynamic volumes, you can use the free partition manager AOMEI Partition Assistant, which will manage your disk in the best status freely with simple few steps, such as create volume, resize volume, or convert dynamic disk into basic disk, etc.