Chapter 10. Disk Partitioning
Fedora Core creates and uses several partitions on
the available hard drives. You may customize both the partitions,
and how the drives on your system are managed.
Section 10.1, “General Information on Partitions” explains drive partitions
in more detail.
||Configuring RAID Devices
RAID facilities enable a group, or array,
of drives to act as a single device. Configure any RAID functions
provided by the mainboard of your computer, or attached controller
cards, before you begin the installation process. Each active RAID
array appears as one drive within Fedora.
On systems with more than one hard drive you may configure Fedora Core to
operate several of the drives as a Linux RAID array without
requiring any additional hardware. Linux software RAID arrays are
explained in Section 10.2, “Disk Druid”.
||Changing Your Mind
The installation process makes no changes to your system until
package installation begins. You may use
to return to previous screens and
change your selections at any time.
Figure 10.1. Partitioning Options Screen
The box on the screen lists the available drives. By default, the
installation process may affect all of the drives on your computer.
To ensure that specific drives are not repartitioned, clear the
check box next to those drives on this list.
The installation process erases any existing Linux partitions on the
selected drives, and replaces them with the default set of
partitions for Fedora Core. All other types of partitions remain unchanged.
For example, partitions used by Microsoft Windows, and system
recovery partitions created by the computer manufacturer, are both
left intact. You may choose an alternative from the drop-down list:
Remove all partitions on selected drives and
create default layout
Avoid this option, unless you wish to erase all of the
existing operating systems and data on the selected drives.
Remove linux partitions on selected drives and
create default layout
If the selected drives have any Linux partitions, this option
removes them and installs Fedora Core into the resulting free space.
This option does not modify partitions assigned to other
non-Linux operating systems. It does not discriminate,
however, between partitions assigned to different Linux
distributions, and will remove all of them.
Use free space on selected drives and create
If the selected drives have free space that has not been
assigned to a partition, this option installs Fedora Core into the
free space. This option ensures that no existing partition is
modified by the installation process.
Create custom layout
You manually specify the partitioning on the selected drives.
The next screen enables you to configure the drives and
partitions for your computer. If you choose this option, Fedora Core
creates no partitions by default.
Review and modify partitioning layout
customize the set of partitions that Fedora Core creates, to configure your
system to use drives in RAID arrays, or to modify the boot options
for your computer. If you choose one of the alternative partitioning
options, this is automatically selected.
Advanced storage options
You want to install Fedora Core to a drive connected through the
iSCSI protocol. Select
Advanced storage options
, then select
Add iSCSI target
, then select
. Provide an IP address and the
iSCSI initiator name, and select
You want to disable a dmraid device
that was detected at boot time.
Choose a partitioning option, and select
10.1. General Information on Partitions
A Fedora Core system has at least three partitions:
Many systems have more partitions than the minimum listed above.
Choose partitions based on your particular system needs. For
example, consider creating a separate
partition on systems that store user data, for the reasons
explained in Section 10.1.3, “Creating a
If you are not sure how best to configure the partitions for your
computer, accept the default partition layout.
The RAM installed in your computer provides a pool of memory for
running systems. Linux systems use
swap partitions to expand this pool, by
automatically moving portions of memory between RAM and swap
partitions if insufficient RAM is available. In addition, certain
power management features store all of the memory for a suspended
system in the available swap partitions. If you manually specify
the partitions on your system, create one swap partition that has
more capacity than the computer RAM.
Data partitions provide storage for files. Each data partition has
mount point, to indicate the system
directory whose contents reside on that partition. A partition
with no mount point is not accessible by users. Data not located
on any other partition resides in the
root) partition is the top of the directory structure. The
/root (sometimes pronounced "slash-root")
directory is the home directory of the user account for system
In the minimum configuration shown above:
All data under the
resides on the
/boot partition. For
example, the file
resides on the
Any file outside of the
/etc/passwd, resides on the
Subdirectories may be assigned to partitions as well. Some
administrators create both
/usr/local partitions. In that case, files
/usr/local, such as
/usr/local/bin/foo, are on the
/usr/local partition. Any other files in
/usr/, such as
/usr/bin/foo, are in the
If you create many partitions instead of one large
/ partition, upgrades become easier. Refer to
the description of
for more information.
||Leave Excess Capacity Unallocated
Only assign storage capacity to partitions that you require
immediately. You may allocate free space at any time, to meet
needs as they arise.
Every partition has a
partition type, to indicate the format of
file system on that partition. The file
system enables Linux to organize, search, and retrieve files
stored on that partition. Use the
file system for data partitions that are not part of LVM, unless
you have specific needs that require another type of file
10.1.2. Understanding LVM
LVM (Logical Volume Management) partitions provide a number of
advantages over standard partitions. LVM partitions are
physical volumes. One or more physical
volumes are combined to form a
volume group. Each volume group's total
storage is then divided into one or more
logical volumes. The logical volumes
function much like standard partitions. They have a file system
type, such as
ext3, and a mount
/boot Partition and LVM
Only an active Linux system may read or write to LVM volumes.
For this reason, the
/boot partition that
initializes your system must be held outside of the LVM
An administrator may grow or shrink logical volumes without
destroying data, unlike standard disk partitions. If the
physical volumes in a volume group are on separate drives or
RAID arrays then administrators may also spread a logical volume
across the storage devices.
You may lose data if you shrink a logical volume to a smaller
capacity than the data on the volume requires. To ensure maximum
flexibility, create logical volumes to meet your current needs,
and leave excess storage capacity unallocated. You may safely
grow logical volumes to use unallocated space, as your needs
||LVM and the Default Partition Layout
By default, the installation process creates data and swap
partitions within LVM volumes, with a separate
10.1.3. Creating a
If you expect that you or other users will store data on the
system, create a separate partition for the
/home directory within a volume group. With
/home partition, you may upgrade
or reinstall Fedora Core without erasing user data files. LVM provides
you with the ability to add more storage capacity for the user
data at a later time.