Windows XP TechNotes: Storage
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Windows XP supports two storage types for disks: Basic
and Dynamic disks both outlined below.
Basic disks support a maximum of 4 Primary partitions,
or 3 when an Extended partition exists. An Extended
partition contains one or more Logical drives. Each
primary partition and each logical drive is assigned a drive
letter and are referred to as basic volumes. Basic
disks support several options for combining disks to increase
the maximum disk space for a volume or to provide fault tolerance.
Note that the following are not supported on Windows XP, but
may exist in Windows NT 4 systems, which then must be converted
to Dynamic disks before they can be used with Windows XP:
- Volume set
- Stripe set (RAID 0)
- Mirror set (RAID 1) - only available on
- Stripe set with parity (RAID 5) - only
available on servers.
Dynamic disks contain volumes instead
of the traditional primary/extended partitions. Dynamic
volumes cannot be accessed by MS-DOS, Windows 95, Windows
98, Windows Millennium Edition (Me) or Windows NT operating
systems. People often incorrectly refer to dynamic
disks as being an NTFS feature, while both basic and dynamic
disks can contain any combination of FAT16, FAT32, or NTFS
volumes. Additionally, dynamic disks are not supported on
the following hardware:
- IEEE 1394 (FireWire) disks
- USB disks
- Removable disks
- Disks in laptops
Disk configurations are named differently
when using dynamic disks. The following list shows the possible
configurations for dynamic disks:
- Simple volume - created from
free space on a single physical disk. A simple volume is
not fault-tolerant. If it is formatted with NTFS it can
be extended to include unallocated space from the same disk,
or another disk, to create a spanned volume.
- Spanned volume - created from
free disk space from 2 to 32 combined disks. Data is written
to the first disk until it is full, then it will write to
the second disk, and so on. If one of the hard disks in
the spanned volume fails, the entire volume set is lost
and needs to be rebuild and restored from backup. Thus,
a spanned volume is not fault-tolerant.
- Striped volume (RAID 0) - created
from free disk space from 2 to 32 combined disks. When data
is written to a striped volume set with 2 disks, the first
block is written to the first disk, the second block to
the second disk, and the third data block is written to
the first disk, and so on, spreading the data evenly over
all disks. A striped volume provides he best performance
for Windows XP systems. A striped volume is not
fault-tolerant and cannot be extended once it is created.
If one of the hard disks in the striped volume fails, the
entire volume set is lost and needs to be rebuild and restored
- Mirrored volume (RAID 1) - a
fault-tolerant volume only available on servers (Windows
2000 and Windows 2003). Requires 2 disks allowing duplication
of all the data on one volume to another disk to provide
redundancy. If one of the disks fails, the data can still
be accessed from the remaining disk. A mirrored volume cannot
- RAID 5 volume - a fault-tolerant
volume only available on servers (Windows 2000 and Windows
2003) created from 3 or more physical disks. When data is
written to the RAID 5 volume, it is distributed over several
disks, and parity information about data blocks on one disk
are stored on the other disks. In case of a disk failure,
the parity information can be used to reconstruct the data
from the missing disk. Because data is spread out over several
disks, a RAID 5 volume offers better read performance
than single or mirrored disks. But because every write requires
the parity calculation, write performance can be
slower. A RAID-5 volume cannot be mirrored or extended.
Disks and volumes are managed by using the
Disk Management console. Right-click My Computer
and select Manage to open Computer Management.
Under Storage click Disk Management. The
following list shows some of the common disk management tasks
on Windows XP:
- Upgrading disks - A basic disk
can be converted to a dynamic disk without losing any of
the data. To upgrade a disk from basic to dynamic, right-click
the disk (left from the partitions), and select Upgrade
To Dynamic Disk. You will need to restart the computer
after the upgrade.
- Reverting disks - If you want
to revert a dynamic disk back to a basic disk, you first
need to remove all the volumes, create a full backup,
and remove all data. After that, right-click the disk and
select Revert To Basic Disk.
- Extending volumes - simple and
spanned volumes formatted with NTFS can be extended to included
unallocated space from the same disk(s) or from a new disk,
without losing any of the data. Only the new space will
be formatted. The boot or system volume
cannot be extended. When a simple volume is extended to
include free space from another physical disk it will become
a spanned volume. To extend a volume, right click the volume
you want to extend, select Extend Volume and select
unallocated space from a dynamic disk.
- Creating a striped volume - To
create a striped volume, right-click unallocated space on
a dynamic disk and select Striped Volume. Remember
that you need at least two physical disks to create a stripe
- Adding disks - When you add a
disk to a Windows XP computer you may need to use the Rescan
option from the Action menu in Disk Management.
If the computer cannot find or initialize the disk you may
need to restart your computer. The Rescan command
updates information about the hardware configuration of
Foreign Disks - When you add a dynamic disk moved from
another computer, you need to import the disk. You can do
this by right-clicking the disk that is marked as Foreign,
and select Import Foreign Disks. When you want
to import a disk that is part of a striped or spanned volume,
you will need to move all the disks that were part of the
- Refresh - The Refresh
option, also located on the Action menu, allows
you to refresh the displayed disk and volume information
about drive letters, file systems, volumes, and removable
media. The Action option also checks to see if previously
unreadable volumes are now readable.
- Formatting - When you create
a new partition or volume, or want to reformat a current
volume, you can format it with either FAT, FAT32 or NTFS.
In addition to selecting the file system you can enter the
volume name, allocation unit size, opt to perform a quick
format, and enable the file and folder compression.
- Marking a partition as active
- When the computer boots it will read the MBR (Master Boot
Record) from the active partition. On a Windows XP computer
this should be the system partition which contains
the files needed to boot Windows (NTLDR, BOOT.INI, etc).
- Remote Disk Management - In addition
to local disk management, Disk Management can be used to
manage disks on a remote computer running Windows 2000/XP/2003.
You have to be a member of the Administrators group on the
- Mounting volumes - When a basic
or dynamic disk is formatted with NTFS it can be assigned
a drive path instead of a drive letter. The disk can be
mounted to an empty NTFS folder allowing it to be accessed
like any ordinary folder. To mount a volume to a folder,
create an empty folder on an NTFS volume, right-click the
new volume and select Change Drive Letter and Paths,
click Add. Select Mount in the following empty NTFS
folder and enter the path to an empty folder on an
Windows XP also offers a command-line tool
to manage disks called Diskpart. You can use the
command-line tool to perform the tasks you would normally
perform in Disk Management, including creating volumes
or upgrading disks to dynamic. The main advantage of this
command-line tool is that it allows you to create scripts
to automate tasks. Click the following link for more information
about the Diskpart tool: A
Description of the Diskpart Command-Line Utility.
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Windows XP supports a wide variety of removable storage devices
such as CD-ROM/DVD-ROM and tape drives. Removable media devices
are labeled Removable in Disk Management.
Disk Management allows you to create a primary partition
on removable media if necessary. A primary partition on removable
media cannot be marked as active and cannot be removed.
The Removable Storage console allows you to manage
the libraries, such as changers and jukeboxes that contain
removable media. Right-click My Computer and click Manage
to open Computer Management. Under Storage click
Removable Storage. If you select Full in
the View menu you will have several extra options, including
creating Media Pools. Software utilities such as
Windows Backup are used to manage the data stored
on media in a media pool.
they are more often found in servers, a tape device can also
be found in Windows XP desktop computers, typically for writing
backups to tape. There are several different types of tape
devices (and tapes), both external and internal.
External tape devices for example, can be connected to an
SCSI, USB or IEEE 1394 interface on the computer. Most USB
and IEEE 1394 devices are plug and play, and do not require
special software or configuration. For others you may need
to install the manufacturers software. If the device is properly
installed it should turn up in the Removable Storage console.
Unless you installed Windows XP using RIS or system imaging
software, the computer will already have a CD or DVD drive
installed. When you do add a new CD/DVD-drive, it will probably
be auto-detected by Windows XP. In some cases, when you have
a CD/DVD recorder for example, you may need to install
Windows XP introduced built-in CD recording software. This
feature allows you to write data to a CD-R or CD-RW without
using third-party CD recording software. To write files or
folders to a CD simply drag them to the DVD/CD-R(W) drive
icon or copy your files and folders and right-click the recorder
and select Write these files to CD. On the Recording
tab of the CD-recorder's Properties you can disable/enable
CD recording, specify the temporary drive location, and select
the recording speed. You cannot duplicate a CD using the built-in
In addition to setting security (Use, Control,
and Modify permissions) on individual items such
as libraries and media pools, you can configure a local security
policy setting that prevents users from formatting and ejecting
removable media. There is also a policy setting you can use
to limit access to a CD-ROM or floppy drive to locally logged-on
exam objectives for the 70-270 exam:
Implementing, Managing, Monitoring, and Troubleshooting Hardware
Devices and Drivers
Implement, manage, and troubleshoot disk devices.
- Install, configure, and manage DVD and CD-ROM devices.
- Monitor and configure disks.
- Monitor, configure, and troubleshoot volumes.
- Monitor and configure removable media, such as tape devices.
here for the complete list of exam objectives.
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