MCSA/MCSE Self-Paced Training Kit (Exam 70-270): Installing ...

10-4 Chapter 10 Managing Data Storage
ical space on the disk. You can also divide a hard disk into multiple partitions for the
purpose of organizing file storage or supporting multiple operating systems on a single
computer. You can create the following three types of partitions on a basic hard disk:
Primary You can configure up to four primary partitions on a computer running
a Windows operating system (three partitions if you also have an extended partition
on the disk). You can configure any primary partition as the active (or bootable)
drive, but only one primary partition is active at a time. Other primary drives
are typically hidden from the operating system and are not assigned a drive letter.
Extended An extended partition provides a way to exceed the four primary partition
limit. You cannot format an extended partition with any file system. Rather,
extended partitions serve as a shell in which you can create any number of logical
partitions.
Logical You can create any number of logical partitions inside an extended partition.
Logical partitions are normally used for organizing files. All logical partitions
are visible, no matter which operating system is started.
Windows stores partition information for basic disks in the partition table, which is not
part of any operating system (it is an area of the drive that is accessible by all operating
systems). Other configuration options, such as drive letter assignments, are controlled
by the operating system and are stored in the Windows Registry.
Dynamic Disks
Windows XP Professional supports dynamic disks (except on portable computers).
Dynamic disks offer several advantages over basic disks:
■ You can divide a dynamic disk into many volumes. The basic disk concept of primary
and extended partitions does not exist when using dynamic disks.
■ Windows stores configuration information for dynamic disks entirely on the disk.
If there are multiple dynamic disks, Windows replicates information to all other
disks so that each disk has a copy of the configuration information. This information
is stored in the last 1 MB of the disk.
■ You can extend dynamic volumes by using contiguous or noncontiguous disk
space. Dynamic volumes can also be made up of areas of disk space on more than
one disk.