GRUB WITH PASSWORD

How to Protect GRUB with Password

STEP 1: Create a password for GRUB, be a root user and open command prompt, type below command. When prompted type grub password twice and press enter. This will return MD5 hash password. Please copy or note it down.

[root@localhost ~]# grub-md5-crypt
Password:
Retype password:
$1$/98ml$JGwe1sR.R9o37DoFIMwHP0

Step 2: Now you need to open the /boot/grub/menu.lst or /boot/grub/grub.conf file and add the MD5 password. Both files are same and symbolic link to each other.

[root@localhost ~]# cat /boot/grub/grub.conf
# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,0)
# kernel /vmlinuz-version ro root=/dev/sda2
# initrd /initrd-[generic-]version.img
#boot=/dev/sda
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title CentOS 6 (2.6.32-573.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-573.el6.x86_64 ro root=UUID=e2d9c130-cb82-4918-abdb-bd5df9d5f8b4 rd_NO_LUKS rd_NO_LVM LANG=en_US.UTF-8 rd_NO_MD SYSFONT=latarcyrheb-sun16 crashkernel=auto KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet
initrd /initramfs-2.6.32-573.el6.x86_64.img

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

STEP 3: Add the newly created MD5 password in GRUB configuration file. Please paste copied password below timeout line and save it and exit. For example, Enter the line password –md5 <add the copied md5 string from step 1> above.

[root@localhost ~]# cat /boot/grub/grub.conf
# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,0)
# kernel /vmlinuz-version ro root=/dev/sda2
# initrd /initrd-[generic-]version.img
#boot=/dev/sda
default=0
timeout=5
password –md5 $1$/98ml$JGwe1sR.R9o37DoFIMwHP0
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title CentOS 6 (2.6.32-573.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-573.el6.x86_64 ro root=UUID=e2d9c130-cb82-4918-abdb-bd5df9d5f8b4 rd_NO_LUKS rd_NO_LVM LANG=en_US.UTF-8 rd_NO_MD SYSFONT=latarcyrheb-sun16 crashkernel=auto KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet
initrd /initramfs-2.6.32-573.el6.x86_64.img
[root@localhost ~]#

STEP 4: Reboot system and try it pressing ‘p‘ to enter password to unlock and enable next features.