How to break Grub password

How to break Grub password

[root@local host]# vi  /etc/grub.conf

Press i key

Then delete these line            #1$$54$77#66$$   

              

Press escape key

: wq!

How to create Password in Grub

We can put the password at the installation time but if we want to put the password in Grub we can put it by the command

[root@local host]# grub-md5-crypt (Enter)

Password *****

Retype *****

#1$$54$77#66$$    (copy this line)

[root@local host]# VI   /etc/grub.conf

Press i key

Move the cursor

Hidden menu

Password   --md5     (paste line)

Press escape key

: wq!   

Grub Repair

Insert Linux DVD in cd-rom then restart own pc

When restart the pc then we write   Linux   rescue (Enter)

Sh 3.1# chroot   /mnt/sysimage (Enter)

Sh3.1# grub-install    /dev/sda (Enter)

Ctrl+d

Ctrl+d

Eject Linux DVD, when start the Linux then we press up arrow key .Then we see open grub page Press C key.

Grub >root   (hd0, no. Of partition in which xp install)

Grub >rootnoverify

Grub >chainloader    +1

Grub >boot

When start Linux then open Terminal

[root@local host]# VI   /etc/grub.conf    (Enter)

Then open grub configuration

Press i key

Title window

Rootnoveify   (hd0, partition no. which xp install)

Chainloader   +1

Press escape key

: wq!

Init   6

Password Break of Linux

Restart   Linux then open Grub page. Then we see Red Hat Enterprise Linux Server (2.6.18-53..........)                              Press E key

Then we see   Kernel/vmlinuz-2.6.18-53......................    Press E key

Then open a new page

 Grub edit > kernel /vmlinuz...........................................rhgbquite 1

Grub edit> boot (Press Enter Key)

Sh 3.1#password (Press Enter Key)

Changing password for user root

UNIX password (Type new password) ***** (Enter)

Retype password *****    (Enter)

Init 6   (Enter)

Create a Local User in Linux

[root@local host]#useradd    rahul (user name which we have add)

[root@local host]#passwd    rahul

[root@local host]# UNIX password   ******

[root@local host]#retypes   ******

Sudo user:- 

In it all the user how are working as administrator are called sudouser.Sudo are the administrator users by default root is a sudo user. If we want to make any local user as a sudouser then we can make him by making changes in the “vi  /etc/sudoers” .This files contains entries of all the root user.

Su - :- This command is used to login from one user to another user. It is the Switch user command.

Case I^ST :- If we are login on one local user & we want to go another local user then we will write the command “su  –  second user name“after this we will give the password of second user.

Case II^nd:-If we are on a local user and we want tom go to root then we will write “su – “then it will as the password by given the root password. We can login by “su – root” command.