Installation guide

Chapter 25. 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 gen-
eral concepts mentioned here may apply.
If you are reasonably comfortable with disk partitions, you could skip ahead to Section 1.4,
“Making Room For Red Hat Enterprise Linux”, for more information on the process of freeing up
disk space to 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.
1. Hard Disk Basic Concepts
Hard disks perform a very simple function — they store data and reliably retrieve it on com-
mand.
When discussing issues such as disk partitioning, it is important to know a bit about the underly-
ing hardware. Unfortunately, it is easy to become bogged down in details. Therefore, this ap-
pendix uses a simplified diagram of a disk drive to help explain what is really happening when a
disk drive is partitioned. Figure 25.1, “An Unused Disk Drive”, shows a brand-new, unused disk
drive.
Figure 25.1. 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.
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.
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