１．设置明文密码

１．１编辑grub.conf

[root@oldboy ~]# vim /boot/grub/grub.conf

1.2插入password

#boot=/dev/sda

default=0
timeout=5
splashp_w_picpath=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
password=
title CentOS (2.6.32-642.11.1.el6.x86_64)

2.设置MD5加密密码

1.1生成MD5密码

[root@oldboy ~]# grub-md5-crypt

1.2编辑grub.conf

[root@oldboy ~]# vim /boot/grub/grub.conf

1.3插入password

#boot=/dev/sda

default=0
timeout=5
splashp_w_picpath=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
password　--md5   ＃加上生的ＭＤ５密码
title CentOS (2.6.32-642.11.1.el6.x86_64)