In this tutorial we will see how to change the default boot order in the Grub 2. Grub 2 is the default boot loader in Ubuntu 9.10, 10.04, 10.10 and 11.04. As the computer starts, GRUB 2 either presents a menu and awaits user input or automatically transfers control to an operating system kernel.

There are two ways to do it. Experienced user can do it by editing the Grub file (located in /etc/default/grub) while I will recommend the beginners to use a GUI tool (Startup Manager) which lets the user select the default operating system or kernel. The tutorial on the Startup Manager can be found here.

Step 1:

Take a look at the boot order in the Grub (when the computer start). Note down the order. Let us assume this is how the boot order arranged:

Linux Kernel 3.0                                                       ——— 0
Linux Kernel 3.0 Recovery Mode                         ——— 1
Previous Kernel Versions                                        ———- 2
Previous Kernel Versions Recovery Mode          ———- 3
Memory Test                                                             ———- 4
Memory Test Recovery                                           ———- 5
Windows 7                                                                 ———- 6

Notice the numbers we assigned to the orders. The numbers represent the position of the particular os/kernel (starting from 0).

Note:

What if you want to make a previous Linux version as your default. The previous Linux Version may consists of all the previous Linux Kernels. Grub 2 provides a nested style sub menu. The previous Linux Versions may seem like this:

Linux Kernel 2.6.39                                                       ——— 0
Linux Kernel 2.6.39 Recovery Mode                         ——— 1
Linux Kernel 2.6.38                                                       ——— 2
Linux Kernel 2.6.38 Recovery Mode                         ——— 3
Linux Kernel 2.6.37                                                       ——— 4
Linux Kernel 2.6.37 Recovery Mode                         ——— 5

Step 2:

Now open the terminal and type the following command:

sudo gedit /etc/default/grub &

The content of the this file looks something like this:

# If you change this file, run ‘update-grub’ afterwards to update
# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
#   info -f grub -n ‘Simple configuration’

GRUB_DEFAULT=0
#GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true
GRUB_TIMEOUT=10
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT=”quiet splash pcie_aspm=force”
GRUB_CMDLINE_LINUX=””

# Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD …)
#GRUB_BADRAM=”0x01234567,0xfefefefe,0x89abcdef,0xefefefef”

# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL=console

# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command `vbeinfo’
#GRUB_GFXMODE=640×480

# Uncomment if you don’t want GRUB to pass “root=UUID=xxx” parameter to Linux
#GRUB_DISABLE_LINUX_UUID=true

# Uncomment to disable generation of recovery mode menu entries
#GRUB_DISABLE_RECOVERY=”true”

# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE=”480 440 1″

Step 3:

In the previous file notice the line: GRUB_DEFAULT=0

This line can be interpreted as “the default kernel/os is at order number 0″ which in this case is Kernel 3.0. All we need to do is to change the line from GRUB_DEFAULT=0 to GRUB_DEFAULT=new_order_number.

For example if we want to make Windows as our default OS, the line will be GRUB_DEFAULT=6. If you want to change the default timeout (wait time before it boots into an OS) of 10 sec you can do that by editing the line GRUB_TIMEOUT=10 to GRUB_TIMEOUT=your_time.

Note:

Remember the previous Linux versions? Talking about the example given in Step 1, if we want Linux Kernel 2.6.37 to be our default we need to change GRUB_DEFAULT=0 to GRUB_DEFAULT=2>4.

Here the previous Linux version is at position 2 and Linux Kernel 2.6.37 is at position 4 inside it.

Step 4:

After changing the grub file, save and close it. Now run the following command:

sudo update-grub

Afterwards, reboot the computer. Enjoy

Related articles

• How to solve: Cannot boot into Windows after installing Ubuntu Linux (computerandu.wordpress.com)
• Ubuntu 11.04 – Simple tip to change Boot Screen image (techtimely.wordpress.com)
• Ubuntu’s tips (pipoliomess.wordpress.com)
• Change Login Screen in Ubuntu 11.04 (techtimely.wordpress.com)