How To Reset linux Password

Hi friends,

I want to reset my linux password and misfortunes i don't now how to reset it.Can anyone help me out with this issue.I would be very thankful to that person.

Sure i will help you out with this for that you need to have KNOPPIX LIVE CD and after that follow the below steps:-

Boot the computer with the KNOPPER CD.

Choose the default startup options. Once Knoppix has loaded, press CTRL-ALT-F3. If knoppix fails to boot the gui properly, you can still access the console with CTRL-ALT-F4. The console is sufficient for our needs. You will see a prompt

Now use the following command.

• sudo su [PRESS ENTER]
  And the prompt will change to:
  
  root@0[knoppix]#
  
  
• dmesg |grep hda [PRESS ENTER]
  We are looking for your primary hard drive, on which Linux is installed.
  Now we find out on which partition the root of your OS lies.
  
  
• fdisk -l /dev/hda [PRESS ENTER]
  
  Normally Linux will probably be on the biggest partition. If the following commands fail on one, try another. Lets assume the root Linux partition is on hda1
  
  
• mount /dev/hda1 /mnt/chroot [PRESS ENTER]
  This changes your live system to the mounted file system. Now any system command you type are applied to the mounted chrooted system.
  
  
• cat /etc/passwd [PRESS ENTER]
  Usually the last entry in this file is the systems "sudoer". This is the first user who installed this system. (And thus a member of the admins group). Lets assume the user is named "xyz"
  
  
• passwd xyz [PRESS ENTER]
  Enter and confirm a password.
  
  
• sync
  Ensuring all changes are written to disk
  
  
• exit [PRESS ENTER]
  
  
• reboot

Thanks for replying me but my boot loader is GRUB.

If you are having Grub as your boot loader try to follow the below steps:-

1. Select the kernel
2. Press the e key to edit the entry
3. Select second line
4. Press the e key to edit kernel entry so that you can append single user mode
5. Append the letter S to the end of the (kernel) line
6. Press ENTER key
7. Now press the b key to boot the Linux kernel into single user mode
8. At prompt type passwd command to reset password:
9. You need to mount at least / and other partitions:
   
   
   • mount -t proc proc /proc
   • mount -o remount,rw /
   
   
10. Change the root password, enter
    
    • passwd
    
    
11. Finally reboot system.