What is Dynamic Disk?

Concept of Dynamic Disk

The Dynamic Disk is a physical disk that manages its volumes by using LDM database. What is the LDM database? LDM is an acronym of Logical Disk Manager, and it is a hidden database which size is 1MB at the end of the Dynamic Disk. The 1MB space records all the information of the volumes on a single disk, and also holds some related information on each dynamic disk. Such as Drive Letter, Volume Label, the begin sector of Volume, Volume size, the file system of Volume, and the current dynamic disk is which one and so on.

Each dynamic disk will hold a these information mentioned if there are several dynamic disk on your computer. This means that all dynamic disks are interrelated. The relevance of each dynamic disk let you will see a “Missing” disk which is shown in Windows Disk Management if you remove a dynamic disk from your system. All this is saved in LDM database, so LDM database is vary important the same as Partition Table of Basic Disk. You can know clearly as follows:

Structure of Dynamic Disk

The blue area at the beginning of Dynamic Disk is the MBR which saves the information of the Partition Table on the disk. This partition table is not the same as one of Basic Disk. Its main function is to make Windows and Other Disk Manager can know the disk is a dynamic disk instead of an empty disk. The blue at the end of the above is the LDM database.


Dynamic Disk and Basic Disk

You can upgrade the basic disk to dynamic easily, but Dynamic disks could not be appropriate in some cases which you need, so you require convert back to basic disk. Using Dynamic Disk Converter is to safely convert dynamic disk to basic, please see How to convert DYNAMIC DISK to BASIC for more information, for Basic Disk, please visit What is Basic Disk.


Dynamic Disk Partition Management

AOMEI Dynamic Disk Manager is a complete solution for dynamic disks and dynamic volumes management which will help you:

Free Download AOMEI Dynamic Disk Manager           Buy Now AOMEI Dynamic Disk Manager


Volumes of Dynamic Disk

On Dynamic Disk, the volumes are divided into Simple Volume, Spanned Volume, Striped Volume, Mirrored Volume and RAID 5 Volume. They have drive letter and volume label to differentiate.

  • Simple Volume
    The simple volume only can be created on the single disk as partition of Basic Disk, but its space can be inconsecutive. The screenshot is as follows:
    Simple Volume of Dynamic Disk

    E: and G: is consecutive simple volume, but F: is inconsecutive on a single dynamic disk.
  • Spanned Volume
    It is created from free space that is linked together from multiple disks (up to 32 disks). The sequence of writing data for Spanned Volume is that the volume on the first disk is filled full and then turn to fill the next dynamic disk. Spanned Volume can allow the fragmentary free space of multiple disks is recomposed as one volume, so it can fully utilize the resources of multi-disk. However, it can not be fault-tolerant volume and can not improve performance of the disk. The following screenshot is shown.
    Spanned Volume of Dynamic Disk

    F: is a Spanned Volume and it utilized the space on Disk 1 and Disk2.
  • Striped Volume
    It's similar with Spanned Volume, and consists of two and more disks. However, the difference is that it can improve the efficiency and performance of disk, because when operating system writes data to Striped Volume, this data will be separated into many pieces of 64KB, and then concurrent writes a different data block to each disk. A striped volume cannot be mirrored or extended and is not fault-tolerant. The screenshot is below:
    Striped Volume of Dynamic Disk

    E: is a Striped Volume, and the space is the same on the two disks, here is 1023MB. Spanned and Striped Volume shows the different color bar to differentiate them in Windows Disk Management.
  • Mirrored Volume
    We can simply understand that Mirrored Volume is a duplicate of Simple Volume. It needs two disks; one stores the data which is being used, and another keep a copy of previous one. When a disk fails, the other one can be used immediately. A Mirrored Volume provides fault-tolerant, and it's also known as RAID-1 as follows:
    Mirrored Volume of Dynamic Disk

    E: is a Mirrored Volume. The data of the Disk1-E is the absolute same as the Disk2-E.
  • RAID-5 Volume
    A RAID-5 requires three disks at least; it not only can enhance the efficiency of the disk but also provide the best fault-tolerant. You could simply consider RAID-5 is a combination of Striped and Mirrored Volume. 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 recreated from the remaining data and the parity. The following is a screenshot of RAID-5.
    RAID-5 Volume of Dynamic Disk

Windows support for Dynamic Volume or not

The following table describes the support case for each Windows.

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

Done!


Copyright © 2009-2013 AOMEI Tech Co., Ltd. All Rights Reserved.