Sunday 2 October 2011

Boot Loader And Its Options


First, let us see what a boot loader is?
It’s a very important part of the computer as without it you won’t be able to start your computer. So, it seems it must be something complicated as it is responsible for starting our machine, but it is not, rather it’s just a small program that loads the operating system in the computer memory whenever we boot our system, and then the control shifts to the operating system which takes care from there onwards.
Now, different questions arise in our mind as “How does it look like?”, ”Can we control it?”,”Can we make changes in it?”,”What are the various types of Boot Loaders?”,”How do we install it?” etc. All these questions will be answered in this Blog and you will have a fair idea about the Boot Loaders after reading this Blog.
Let us first see different types of Boot Loaders and how do they look like.
1.     GNU GRUB (GRand Unified Boot Loader)
·        Derived from GRUB.
·        Multiboot Boot Loader.
·        How Does it look like?(See Below)

The image above shows the GNU GRUB Boot Loader, and you can see the it shows different OS which can be loaded in the computer.
2.     LILO
·        Most popular Boot Loader for Linux.
·        Can be configured to Boot multiple Os as well.
·        Let’s see how it looks.
 


3.     BOOTMGR
·        Multiboot manager.
·        Let’s see how it looks.
 
                                                                        Image source - internet
4.     Plop Boot Manager 
·        Can boot OS from hard disk,USB,CD/DVD or Floppy Drive.
·        No extra partition required for boot manager.
·        How does it look like?

                 
                                                                Image source - internet






Now let us study some of them in Brief and how they can be installed and explore various options in it.
1.     Windows Boot Manager
Windows Boot Manager can boot different Operating Systems including all versions of Windows as well as linux.
It automatically gets installed when we install our sysyem with Windows 7.
To edit the Boot Manager-
1.Backup a copy of boot.ini
·        Right click on my computer-click properties-on the advanced tab click settings under startup and recovery.
·        Click startup and recovery-click edit which will open the notepad file ready for editing.Save this in some different place before editing.

·        Now we can modify the boot.ini file and change default OS, timeout value or even add a new operating system.
·        Open the command prompt and type boot\? which will show the help and parameters for BOOTCFG.exe.
·        To add an OS-type following command at the command prompt:
bootcfg /copy /d Operating System Description /ID#
·        To delete an OS.:- bootcfg /delete /ID#
·        To set time-out :- bootcfg /timeout# ,where # is the time in which the user should choose an operating system, else the default OS boots automatically.


GRUB
If your computer already runs on window operating system and you want to install Ubuntu as well on it then boot it in a different partition not containing your windows programme files.
When you install Ubuntu you automatically get a new boot loader which helps you choose from different operating systems present in your machine.
We can easily configure our GRUB boot loader, let’s see some of the ways.
·        Setting password.
Open the terminal – type grub – and use the  md5crypt command to set a hashed password.
                          grub> md5crypt
                          Password: **********
Encrypted: $1$U$JK7xFegdxWH6VuppCUSIb

·        To add a new operating system to the GRUB menu-
Lets say you wish to add a new operating system called “xyz” to the GRUB menu list.
To add this, all you need to do is add its entry to the menu.lst using the following commands.
title xyz
root (hdX,Y)  (X,Y represent the partition in which the OS is installed)
chainloader +1

You can also edit the GRUB menu at the time when GRUB asks for the OS to be booted by pressing ‘e’.
 
                        Image - internet                                                                                      

                    Blog By – Abhishek Kumar(2011006)

1 comment:

  1. Instead of all this, u can simply go to start and run System Configuration which gives u the rights to edit the boot.ini file like changing the default OS and OS Boot loader options directly ...

    ReplyDelete