Red Hat ENTERPRISE LINUX 5 - VIRTUAL SERVER ADMINISTRATION, Руководство по установке

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Installing GRUB
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9.3. Installing GRUB
If GRUB was not installed during the installation process, it can be installed afterward. Once installed,
it automatically becomes the default boot loader.
Before installing GRUB, make sure to use the latest GRUB package available or use the GRUB
package from the installation CD-ROMs. For instructions on installing packages, refer to the chapter
titled
Package Management with RPM
in the
Red Hat Enterprise Linux Deployment Guide
.
Once the GRUB package is installed, open a root shell prompt and run the command
/sbin/grub-
install <location>
, where
<location>
is the location that the GRUB Stage 1 boot loader
should be installed. For example, the following command installs GRUB to the MBR of the master IDE
device on the primary IDE bus:
/sbin/grub-install -/dev/hda
The next time the system boots, the GRUB graphical boot loader menu appears before the kernel
loads into memory.
Important — GRUB and RAID
GRUB
cannot construct a software RAID. Therefore, the
/boot
directory must reside on
a single, specific disk partition. The
/boot
directory cannot be striped across multiple
disks, as in a level 0 RAID. To use a level 0 RAID on your system, place /boot on a
separate partition outside the RAID.
Similarly, because the
/boot
directory must reside on a single, specific disk partition,
GRUB
cannot boot the system if the disk holding that partition fails or is removed from the
system. This is true even if the disk is mirrored in a level 1 RAID. The following Red Hat
Knowledgebase article describes how to make the system bootable from another disk in
the mirrored set:
http://kbase.redhat.com/faq/docs/DOC-7095
Note that these issues apply only to RAID that is implemented in software, where the
individual disks that make up the array are still visible as individual disks on the system.
These issues do not apply to hardware RAID where multiple disks are represented as a
single device.
9.4. GRUB Terminology
One of the most important things to understand before using GRUB is how the program refers to
devices, such as hard drives and partitions. This information is particularly important when configuring
GRUB to boot multiple operating systems.
9.4.1. Device Names
When referring to a specific device with GRUB, do so using the following format (note that the
parentheses and comma are very important syntactically):
( <type-of-device><bios-device-number> , <partition-number> )
The
<type-of-device>
specifies the type of device from which GRUB boots. The two most
common options are
hd
for a hard disk or
fd
for a 3.5 diskette. A lesser used device type is also