Giving grub a password

[root@vikas ~]# grub-md5-crypt
Password:
Retype password:
$1$0momt$iyfphL4LSrQse/JHNI471/
[root@vikas ~]#

Now add password in the /etc/grub.conf
password -md5 $1$0momt$iyfphL4LSrQse/JHNI471/

Now every time you login first you need to give the grub password as well, whether you you login as a single user or a normal boot.