Using disk management
The concept of disk management has been useful in understanding how
disks are used for several versions of Microsoft Windows, and Windows 8
is no exception. You can open the Disk Management utility by one of
three ways:
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Searching for Disk Management and then tapping or clicking Create And Format Hard Disk Partitions
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Selecting it from the Storage section of the computer management console
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Adding it to a custom Microsoft Management Console (MMC)
The Disk Management utility provides an overview of all the disks within a computer, as shown in Figure 1.
The Disk
Management snap-in has two main sections in the results pane. The top
section shows a list view of the physical and logical disks installed
in a computer. The bottom section shows a graphical representation of
the disks in the computer and any partitions or logical disks they contain. Both sections of the window display the same information; only the format is different.
In addition to determining the types of disks or volumes your
computer contains, the Disk Management console displays the following
information:
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Capacity The maximum size of the disk
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Free Space The amount of space remaining
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Percentage of space free The amount of space remaining displayed as a percentage of capacity
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Disk Type The type of disk: basic or dynamic
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File System The file system used to format the disk
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Status The overall health of the disk and which roles this partition has
A basic disk is the most common type of disk Windows uses. This disk
type can contain partitions that segregate information stored on a
physical disk. Basic disks use a Master Boot Record partitioning style to maintain backward compatibility, but newer operating systems support the GUID Partition Table (GPT).
On a basic disk, partitions can be extended to consume all the
available free space on the same disk, but they cannot extend beyond
the boundaries of that disk. Basic disks support the following actions:
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Creation and deletion of primary and extended partitions
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Creation and deletion of logical drives within an extended partition
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Formatting partitions and setting their status to active to enable them for use
A dynamic disk supports options that are not available on a basic
disk, including volumes that span multiple disks and fault-tolerant
volumes. In addition to these features, dynamic volumes use a database
to help manage the volumes contained on a dynamic disk. Replicas of the
dynamic disk database are kept on each dynamic disk, which can aid in
repair of dynamic volumes.
The ability to store information in noncontiguous space that can
span multiple disks can be advantageous when fault tolerance is needed.
Although spreading data across disks can be helpful, the ability to
configure different types of volumes can be a lifesaver for your
information. Dynamic disks support the following actions:
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Creating and deleting simple, spanned, striped, mirrored, and RAID-5 volumes
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Extending a simple or spanned volume
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Removing a mirror or breaking a mirrored volume into two volumes
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Repairing RAID-5 or mirrored volumes
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Reactivating missing or offline disks
Both these disk
types can be useful in different situations; however, basic disks are
used most commonly for personal computers or mobile devices.
Note
MASTER BOOT RECORD OR GLOBALLY UNIQUE IDENTIFIER PARTITIONS AVAILABLE
Partitions can use the Master Boot Record (MBR) or globally unique identifier (GUID) style. MBR
partitions are selected as the default style for backward
compatibility. They also allow only four primary partitions or three
primary partitions and one extended partition. The partition information for an MBR partition is stored at the front of the disk in the first MB of space. The layout of information on these partitions is always contiguous.
GUID-style partitions are supported in Microsoft Windows Server 2003
SP1 and later. They allow up to 128 primary partitions. Logical drives
and extended partitions are not necessary with this style of partition.
The GPT style also supports partition sizes larger than 2 terabytes (TB).
Basic disks support partitions. The two types of partitions available for use on a basic disk are:
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Primary This
partition type can contain only one logical drive and is the required
type for logical disks that start Windows; that is, the C drive.
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Extended This
partition type can contain multiple logical drives but cannot start
Windows. Each logical partition can be assigned its own drive letter.
There can be only one extended partition per physical disk.
Dynamic disks support volumes, of which five volume types are
available. Some are very similar to the partitions mentioned earlier,
and some provide fault tolerance for the data stored on them:
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Simple
This volume type operates the same way as a primary
partition on a basic disk. Simple volumes can be mirrored, but if they
are extended across multiple disks, they become spanned volumes.
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Spanned This volume type combines unallocated space from multiple disks into one logical volume. Up to 32 disks can be included in a spanned
volume. After a spanned volume is created, no portion of it can be
deleted. If you delete any part of the spanned volume, you delete the
entire volume. Spanned volumes must use the NTFS file system or use an
unformatted portion of the disk. They provide no fault tolerance.
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Striped
This volume type
improves disk input/output (reads and writes) by spreading information
in equal parts across multiple disks. A spanned volume uses available
free space from included disks, but a striped volume evenly distributes the information across included disks for more efficient use. This volume
type offers no fault tolerance. In addition, striped volumes do not
support mirroring or extension. If one disk in the stripe set fails,
the entire volume fails.
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Mirrored This
volume type provides fault tolerance by creating a volume copy on
another disk. The copy is an exact duplicate of the original volume. In
the event of failure of a mirrored volume, the computer can continue to function by using the other portion of the mirror.
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RAID-5
This volume type
is the most fault tolerant of all available types. RAID-5 volumes
stripe data and parity across three or more disks. Parity is a value
calculated to ensure that a failed volume can be rebuilt from that
information plus the remaining available volumes.
Actions available by using Disk Management
In addition to displaying information about disks, partitions, and
volumes, the Disk Management utility can help you manage certain
aspects of these items from a single, straightforward interface. The
actions available from Disk Management depend on the disk type and the
partition or volume selected. The entire list of actions that can be
performed on partitions or volumes is as follows:
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Open Selecting this option opens the partition or volume in File Explorer with no tree view.
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Explore Selecting this option opens the partition or volume in File Explorer with the tree view.
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Mark Partition As Active Selecting this option sets the status of the partition as active.
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Change Drive Letter And Paths Selecting this option enables you to change the drive letter or folder path to a partition.
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Format Selecting this option erases all information from a partition.
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Extend Volume Selecting this option increases the size of a volume by consuming an amount of available free space.
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Shrink Volume Selecting this option decreases the size of a volume by returning an amount of space to the free space pool.
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Add Mirror Selecting this option creates a mirror of this volume on another disk.
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Delete Volume Selecting this option removes the volume and all the data it contains.
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Properties Selecting this option displays the Disk Properties window for the selected item.
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Help Selecting this option displays Disk Management help.
These actions
are available from the context menu (press and hold or right-click) for
a volume or partition. Actions unavailable for a volume or partition
appear dimmed, depending on the item selected.
An example of using the Disk Management tools discussed to this
point might help you understand how the tools work. Suppose you have a
virtual machine running Windows 8 to use for testing purposes. The
computer has two virtual hard disks attached: one for Windows 8 and one
for other documents and testing of different features for hard disks in
the operating system. Because you keep a copy of the documentation
being created for the tests on the second virtual hard drive, it is
quickly filling up. You would like to extend the drive to add 50
percent more space to the current 500 MB size. To extend the size of
the virtual machine by using Disk Management, complete the following
steps:
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Open the Start screen.
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Search for Disk Management.
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Select Settings from the results list.
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Select Create And Format Hard Disk Partitions.
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Locate the 500-MB disk you want to extend in Disk Management and select it.
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Press and hold or right-click the volume on that disk to display the context menu.
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Select Extend Volume from the context menu.
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Click or tap Next to skip the Extend Volume Wizard welcome page.
Note
CHANGING THE SIZE OF THE VOLUME
The volume will appear in the Extend Volume Wizard in the selected
window with all the space available on the virtual hard disk listed as
the size. You can change this by entering the amount of space you want
to add in the Select The Amount Of Space In MB box.
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Enter the amount of space by which to increase the volume. To
increase the amount of space by 50 percent, enter 250 MB in the Select
The Amount Of Space In MB box.
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Tap or click Next.
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Review the changes that will be made.
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Tap or click Finish to complete the extension.
In addition to the actions for partitions and volumes, other actions
are available only on a per-disk basis. These actions are also
available in a context menu by pressing and holding or right-clicking
the disk item. Disks are listed along the far-left side of the
graphical portion of the Disk Management snap-in. Actions available for disks include:
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New Spanned Volume
Select this option to create a new spanned volume.
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New Striped Volume
Select this option to create a new striped volume.
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New Mirrored Volume
Select this option to create a new mirrored volume; remember that two disks are required for this action.
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New RAID-5 Volume
Select this option to create a new RAID-5 volume; a minimum of three disks are required for this action.
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Convert To Dynamic Disk Select this option to convert a basic disk to a dynamic disk.
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Convert To GPT Disk
Select this option to change the partition style from Master Boot Record to GUID Partition Table.
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Offline Select this option to set the status of the disk to offline, making it unusable by the computer.
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Properties Select this option to display the device properties of the disk.
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Help Select this option to display Disk Management help.
As with partition options, disk options depend on the type of disk that is selected. Options for dynamic disks appear dimmed if a basic disk is selected.
Important
DYNAMIC DISKS CANNOT BE CONVERTED TO BASIC DISKS
Conversion from a basic disk to a dynamic disk is a one-way process.
After a disk is dynamic, it cannot be converted back to a basic disk
without being deleted first, which will cause data loss.
The Disk Management snap-in is a great tool for determining what you have. It provides an easy way to see details about all your disks at a glance. Like other snap-ins ,
Disk Management can be pointed at remote computers to examine their
disks. You cannot use the same instance of Disk Management to view
multiple computers at the same time; to access multiple computers, you
must either add multiple instances of the Disk Management snap-in to a
custom MMC or change the computer being viewed by the snap-in for each
computer you are interested in viewing.
