Ubuntu:Edgy th/BootMenu

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Boot Menu

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How to gain root user access without login

  • Read #General Notes
  • Easiest method (will not work if GRUB menu password is set)
    • Boot-up computer
    • If GRUB menu is hidden, press 'Esc' to enter the GRUB menu
    • Select 
Ubuntu, kernel 2.6.10-5-386 (recovery mode)
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How to modify kernel boot-up arguments, to gain root user access

  • Read #General Notes
  • Boot-up computer
  • If GRUB menu is hidden, press 'Esc' to enter the GRUB menu
  • If GRUB password is set, press 'p' to unlock the GRUB menu
  • Select 
Ubuntu, kernel 2.6.10-5-386
  • Press 'e' to edit the commands before booting
  • Select 
kernel /boot/vmlinuz-2.6.10-5-386 root=/dev/hda2 ro quiet splash
  • Press 'e' to edit the selected command in the boot sequence
  • Add "rw init=/bin/bash" to the end of the arguments 
grub edit> kernel /boot/vmlinuz-2.6.10-5-386 root=/dev/hda2 ro quiet splash rw init=/bin/bash
  • Press 'b' to boot
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How to use Ubuntu Installation CD, to gain root user access

  • Read #General Notes
  • Boot-up computer into Ubuntu Installation CD
  • At "boot:" prompt, add "rescue" to the argument 
boot: rescue
  • Follow the instructions on screen
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How to change root user/main user password if forgotten 

# passwd root
  • To change main user password 
# passwd system_main_username
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How to change GRUB menu password if forgotten 

grub

grub> md5crypt
Password: ****** (ubuntu)
Encrypted: $1$ZWnke0$1fzDBVjUcT1Mpdd4u/T961 (encrypted password)
grub> quit

sudo cp /boot/grub/menu.lst /boot/grub/menu.lst_backup
gksudo gedit /boot/grub/menu.lst
  • Find this line 
...
password --md5 $1$gLhU0/$aW78kHK1QfV3P2b2znUoe/
...
  • Replace with the following line 
password --md5 $1$ZWnke0$1fzDBVjUcT1Mpdd4u/T961 (encrypted password above)
  • Save the edited file
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How to restore GRUB menu after Windows installation

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How to identify the name of the boot drive (hd0, hd1, hd2, etc)

Press "c" on boot menu. If you don't see a boot menu, press ESC key first when booting to show the boot menu.

Type: 

root (hd0,0)

Most likely you will get "(hd0,0) ext2fs", which should be your current Linux drive. Now change hd0 to hd1 to see what is there. 

root (hd1,0)

If you get "(hd1,0) filesystem type unknown, partition type 0x7", then hd1 is a Windows drive.

Now change hd1 to hd2, keep going until you reach hd7.

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How to add Windows entry into GRUB menu

e.g. Assumed that /dev/hda1 is the location of Windows partition 
sudo cp /boot/grub/menu.lst /boot/grub/menu.lst_backup
gksudo gedit /boot/grub/menu.lst
  • Append the following lines at the end of file 
title		Microsoft Windows
rootnoverify	(hd0,0)
savedefault
makeactive
chainloader	+1
  • Save the edited file
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How to boot into Windows installed on a seperate SATA drive

This configuration applies to people who have Linux installed on a IDE drive, and Windows installed on a seperate SATA. The IDE drive boots first, so we need to add an entry to the boot menu on the Linux disk. Here we assume the name of your Windows drive is hd1. If you are not sure, click the link above to find out. 

sudo cp /boot/grub/menu.lst /boot/grub/menu.lst_backup
gksudo gedit /boot/grub/menu.lst
  • Append the following lines at the end of file. 
title           Windows XP on SATA drive
map (hd0) (hd1)
map (hd1) (hd0)
chainloader (hd1,0)+1
  • Save the edited file
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How to read Linux partitions (ext2, ext3) in Windows machine

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