An Introduction To Disk Partitions; Hard Disk Basic Concepts; It Is Not What You Write, It Is How You Write It - Red Hat ENTREPRISE LINUX 5 Installation Manual

Chapter 26.

An Introduction to Disk Partitions

Note
This appendix is not necessarily applicable to non-x86-based architectures. However, the
general concepts mentioned here may apply.
This appendix is not necessarily applicable to non-x86-based architectures. However, the general
concepts mentioned here may apply.
If you are reasonably comfortable with disk partitions, you could skip ahead to
Room For Red Hat Enterprise
prepare for a Red Hat Enterprise Linux installation. This section also discusses the partition naming
scheme used by Linux systems, sharing disk space with other operating systems, and related topics.

26.1. Hard Disk Basic Concepts

Hard disks perform a very simple function — they store data and reliably retrieve it on command.
When discussing issues such as disk partitioning, it is important to know a bit about the underlying
hardware. Unfortunately, it is easy to become bogged down in details. Therefore, this appendix uses
a simplified diagram of a disk drive to help explain what is really happening when a disk drive is
Figure 26.1, "An Unused Disk
partitioned.
Figure 26.1. An Unused Disk Drive
Not much to look at, is it? But if we are talking about disk drives on a basic level, it is adequate. Say
that we would like to store some data on this drive. As things stand now, it will not work. There is
something we need to do first.

26.1.1. It is Not What You Write, it is How You Write It

Experienced computer users probably got this one on the first try. We need to format the drive.
Formatting (usually known as "making a file system") writes information to the drive, creating order out
of the empty space in an unformatted drive.
Figure 26.2. Disk Drive with a File System
Linux", for more information on the process of freeing up disk space to
Drive", shows a brand-new, unused disk drive.
Section 26.1.4, "Making
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