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

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Is Your RAM Not Being Recognized?
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If you cannot remember your root password, boot your system as
linux single
.
Itanium users must enter boot commands with
elilo
followed by the boot command.
If you are using an x86-based system and GRUB is your installed boot loader, type
e
for edit when the
GRUB boot screen has loaded. You are presented with a list of items in the configuration file for the
boot label you have selected.
Choose the line that starts with
kernel
and type
e
to edit this boot entry.
At the end of the
kernel
line, add:
single
Press
Enter
to exit edit mode.
Once the boot loader screen has returned, type
b
to boot the system.
Once you have booted into single user mode and have access to the
#
prompt, you must type
passwd
root
, which allows you to enter a new password for root. At this point you can type
shutdown -r
now
to reboot the system with the new root password.
If you cannot remember your user account password, you must become root. To become root, type
su
-
and enter your root password when prompted. Then, type
passwd <username>
. This allows you to
enter a new password for the specified user account.
If the graphical login screen does not appear, check your hardware for compatibility issues. The
Hardware Compatibility List
can be found at:
http://hardware.redhat.com/hcl/
6.4.6. Is Your RAM Not Being Recognized?
Sometimes, the kernel does not recognize all of your memory (RAM). You can check this with the
cat /proc/meminfo
command.
Verify that the displayed quantity is the same as the known amount of RAM in your system. If they are
not equal, add the following line to the
/boot/grub/grub.conf
:
mem= xx M
Replace
xx
with the amount of RAM you have in megabytes.
In
/boot/grub/grub.conf
, the above example would look similar to the following:
# NOTICE: You have a ­/boot partition. This means that
# all kernel paths are relative to ­/boot/
default=0
timeout=30
splashimage=(hd0,0)/grub/splash.xpm.gz
title Red Hat Enterprise Linux (2.6.9­5.EL)