[howto] Enable/Disable GRUB Password

NOTE: This is not a rock solid secured way of disabling access to your pc. But atleast for those “Windoze users” who have no clue wtf is a grub, it’s going to be pretty effective! I’m going to teach you how to enable as well as disable grub password.

Enable GRUB password:

1. Open terminal and type as root:

# cp /boot/grub/menu.lst /boot/grub/menu.lst.backup

2. Now that your GRUB is backed up. Type:

# grub

grub> md5crypt

Password: ******** [Type in the password that you want to encrypt!]

Now copy the encrypted message it gives you!

grub> quit

3. Open /boot/grub/menu.lst.backup and paste the message after initrd line. If you have a number of Grub entries , you must paste it [or use a different encrypted password using the above method] for every entry that you want to password protect! Use it like this:

title           Debian GNU/Linux, squeeze/sid
root            (hd0,1)
kernel          /boot/vmlinuz-2.6.30-1-amd64 root=/dev/hda2 ro splash quiet vga=791
initrd          /boot/initrd.img-2.6.30-1-amd64

password – -md5 gasgd6876b2dsd2d/

paste the code after “password – -md5”

Note: Since wordpress has the weird habit of showing double hyphen as a single large one, I put a space in between the two, you just need to put two hyphens without any space in between!

Disable/Hack GRUB password:

1. You need a Linux live CD for this.

2. Insert the CD and boot from it.

3. In command line [or if you’re using ubuntu cd 😛 open a terminal and type]:

$ su

# fdisk -l [to check the name of the root directory]

# mount -t ext3 -o rw /dev/sda2 /mnt

[change ext3 to ext4 and /dev/sda2 according o the fdisk -l output]

# chroot /mnt /bin/bash

# nano /boot/grub/menu.lst

Now just remove the password line from the grub menu. 😛 Simple eh? Now save , unmount the partition and reboot!

[howto] Enable/Disable Root Login

NOTE: IF YOUR DISTRIBUTION HAS DISABLED ROOT LOGIN THEN IT’S FOR A GOOD REASON! ROOT LOGINS CAN BE EXTREMELY DANGEROUS, SPECIALLY IF YOU ARE NEW TO LINUX ENVIRONMENT.

Why so? Simply because becoming the root user[like the administrator login in Windows] you will have the ultimate power of your system which if used incorrectly can destroy your data and even your system as a whole. SO USE THIS AT YOUR OWN RISK!

ENABLING ROOT ACCOUNT: Type in  terminal :

sudo passwd root

and enter the password for root user and from next time you can use username “root” and this password to login or use su to have root access.

DISABLING ROOT ACCOUNT: Type in terminal:

passwd -l root

And done! 😉