Add Grub Password After Linux Installation

Setting a grub password after installing Linux OS is as follows;

• login as root and execute 'grub' command in terminal/konsole. prompt will change to 'grub>'
  execute md5crypt to generate password hash.

grub> md5crypt

• it will prompt you for password, enter the password which you are going to set for GRUB. it will display encrypted password hash.

Password: ******
Encrypted: $1$jxcdN0$hVHViq1aiPf8FziuGJGZp0

• Note down encrypted password hash and exit grub mode:

grub> quit

• edit /boot/grub/grub.conf file and insert encrypted password in between "splashimage" and "title" lines.

E.g.
splashimage=(hd0,0)/boot/grub/splash.xpm.gz
password --md5
title Fedora X
Reference:
http://www.linuxforums.org/forum/red-hat-fedora-linux/69395-add-grub-password-after-installation.html