How to recover root password?

[mak.ripon]

I forgot root password.
I tried to follow this.
http://www.ubuntugeek.com/how-to-rec...er-ubuntu.html

But there is not waiting time for grub2.
I hit ESC but failed ,ubuntu is booted by default.

Now how can i recover root password?

[mak.ripon]

cat /boot/grub/grub.cfg

#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by /usr/sbin/grub-mkconfig using templates
# from /etc/grub.d and settings from /etc/default/grub
#

### BEGIN /etc/grub.d/00_header ###
if [ -s /boot/grub/grubenv ]; then
  have_grubenv=true
  load_env
fi
set default="0"
if [ ${prev_saved_entry} ]; then
  saved_entry=${prev_saved_entry}
  save_env saved_entry
  prev_saved_entry=
  save_env prev_saved_entry
fi
insmod ext2
set root=(hd1,14)
search --no-floppy --fs-uuid --set b5cf8e0c-5951-4f31-8699-dc966237fd40
if loadfont /usr/share/grub/unicode.pf2 ; then
  set gfxmode=640x480
  insmod gfxterm
  insmod vbe
  if terminal_output gfxterm ; then true ; else
    # For backward compatibility with versions of terminal.mod that don't
    # understand terminal_output
    terminal gfxterm
  fi
fi
if [ ${recordfail} = 1 ]; then
  set timeout=-1
else
  set timeout=10
fi
### END /etc/grub.d/00_header ###

### BEGIN /etc/grub.d/05_debian_theme ###
set menu_color_normal=white/black
set menu_color_highlight=black/white
### END /etc/grub.d/05_debian_theme ###

### BEGIN /etc/grub.d/10_linux ###
menuentry "Ubuntu, Linux 2.6.31-14-generic" {
        recordfail=1
        if [ -n ${have_grubenv} ]; then save_env recordfail; fi
    set quiet=1
    insmod ext2
    set root=(hd1,14)
    search --no-floppy --fs-uuid --set b5cf8e0c-5951-4f31-8699-dc966237fd40
    linux    /boot/vmlinuz-2.6.31-14-generic root=UUID=b5cf8e0c-5951-4f31-8699-dc966237fd40 ro   quiet splash
    initrd    /boot/initrd.img-2.6.31-14-generic
}
menuentry "Ubuntu, Linux 2.6.31-14-generic (recovery mode)" {
        recordfail=1
        if [ -n ${have_grubenv} ]; then save_env recordfail; fi
    insmod ext2
    set root=(hd1,14)
    search --no-floppy --fs-uuid --set b5cf8e0c-5951-4f31-8699-dc966237fd40
    linux    /boot/vmlinuz-2.6.31-14-generic root=UUID=b5cf8e0c-5951-4f31-8699-dc966237fd40 ro single 
    initrd    /boot/initrd.img-2.6.31-14-generic
}
### END /etc/grub.d/10_linux ###

### BEGIN /etc/grub.d/20_memtest86+ ###
menuentry "Memory test (memtest86+)" {
    linux16    /boot/memtest86+.bin
}
menuentry "Memory test (memtest86+, serial console 115200)" {
    linux16    /boot/memtest86+.bin console=ttyS0,115200n8
}
### END /etc/grub.d/20_memtest86+ ###

### BEGIN /etc/grub.d/30_os-prober ###
if [ ${timeout} != -1 ]; then
  if keystatus; then
    if keystatus --shift; then
      set timeout=-1
    else
      set timeout=0
    fi
  else
    if sleep --interruptible 3 ; then
      set timeout=0
    fi
  fi
fi
### END /etc/grub.d/30_os-prober ###

### BEGIN /etc/grub.d/40_custom ###
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
### END /etc/grub.d/40_custom ###

[sisco311]

By default, the root account password is locked in Ubuntu. Did you set up one or do you want to reset your admin user's (sudo) password?

[mak.ripon]

By default, the root account password is locked in Ubuntu. Did you set up one or do you want to reset your admin user's (sudo) password?

Yes,i want to change sudo(admin) password.

[coffeecat]

I tried to follow this.
http://www.ubuntugeek.com/how-to-rec...er-ubuntu.html

But there is not waiting time for grub2.
I hit ESC but failed ,ubuntu is booted by default.

Now how can i recover root password?

That link is out-of-date. You'd do better following this one:

http://www.psychocats.net/ubuntu/resetpassword

For grub2, you need to press shift, not ESC. Then boot into recovery mode and follow the rest of the guide. You don't need to edit the grub kernel line as your link suggests.

By the way, it's your own password (which has administrator rights) not root's you are resetting. The root password is disabled in a default install of Ubuntu.