Skip to main content

A brief tutorial on GRUB boot loader

By RoCk StAr DeViL
A boot loader is a software program that runs when a computer boot. It's responsible for loading and transferring control to an operating system kernel software. The kernel, in turn, initializes the rest of the operating system. 
GRUB (GRand Unified Boot-loader) or GNU GRUB is a very powerful multi-boot loader, which can load a wide variety of free operating systems, as well as proprietary operating systems with chain-loading. GRUB is designed to address the complexity of booting a personal computer. One of the important features in GRUB is flexibility; GRUB understands filesystems and kernel executable formats, so you can load an arbitrary operating system the way you like, without recording the physical position of your kernel on the disk. Thus you can load the kernel just by specifying its file name and the drive and partition where the kernel resides.
When booting with GRUB, you can use either a command-line interface or a menu interface. Using the command-line interface, you type the drive specification and file name of the kernel manually. In the menu interface, you just select an OS using the arrow keys. The menu is based on a configuration file which you prepare beforehand. While in the menu, you can switch to the command-line mode and vice-versa. You can even edit menu entries before using them.

Contents of GRUB
Installed programs:              
grub-bios-setup, grub-editenv, grub-fstest, grub-install, grub-kbdcomp, grub-menulst2cfg, grub-mkconfig, grub-mkimage, grub-mklayout, grub-mknetdir, grub-mkpasswd-pbkdf2, grub-mkrelpath, grub-mkrescue, grub-mkstandalone, grub-ofpathname, grub-probe, grub-reboot, grub-script-check, grub-set-default, grub-sparc64-setup


Installed directories:                
/usr/lib/grub, /etc/grub.d, /usr/share/grub, /boot/grub

Short Descriptions
grub-bios-setup                 Is a helper program for grub-install
grub-editenv                      A tool to edit the environment block
grub-fstest                         Tool to debug the filesystem driver
grub-install                        Install GRUB on your drive
grub-kbdcomp                   Script that converts an xkb layout into one recognized by GRUB
grub-menulst2cfg              Converts a GRUB Legacy menu.lst into a grub.cfg for use with GRUB 2
grub-mkconfig                   Generate a grub config file
grub-mkimage                   Make a bootable image of GRUB
grub-mklayout                   Generates a GRUB keyboard layout file
grub-mknetdir                   Prepares a GRUB netboot directory
grub-mkpasswd-pbkdf2    Generates an encrypted PBKDF2 password for use in the boot menu
grub-mkrelpath                 Makes a system pathname relative to its root
grub-mkrescue                  Make a bootable image of GRUB suitable for a floppy disk or CDROM/DVD
grub-mkstandalone           Generates a standalone image
grub-ofpathname               Is a helper program that prints the path of a GRUB device
grub-probe                         Probe device information for a given path or device
grub-reboot                        Sets the default boot entry for GRUB for the next boot only
grub-script-check              Checks GRUB configuration script for syntax errors
grub-set-default                 Sets the default boot entry for GRUB
grub-sparc64-setup           Is a helper program for grub-setup

EDIT GRUB File
GRUB configuration file is located in grub directory. Pathname: /boot/grub/grub.cfg. This file is required when you want to change the order in boot menu.
Labels:

Comments

Post a Comment

plz add ur comment here

Popular posts from this blog

Wordpress hacking - How to install / run wpscan on windows xp / windows 7 / windows 10

By RoCk StAr DeViL
HOW TO RUN WPSCAN ON WINDOWS Byrockstardevil Requirements: rubyinstaller Development Kit for rubyinstaller curl DLL for windows : libcurl.dll 1 - install rubyinstaller you must have Ruby 2.2.3 version . download links here : http://rubyinstaller.org/downloads/ for more info : https://github.com/oneclick/rubyinstaller/wiki 2 - install Development Kit for rubyinstaller download link : http://rubyinstaller.org/downloads/ how to install : https://github.com/oneclick/rubyinstaller/wiki/Development-Kit if you face that problem  "unknown encoding name -  (ArgumentError)" just type "chcp 1252" in cmd and hit enter 3 - install libcurl.dll A - Download libcurl.dll from : http://www.confusedbycode.com/curl/ B - copy libcurl.dll copy  libcurl.dll into ruby bin folder or wpscan folder and make sure to add it to your PATH. I also added .DLL to PATHEXT ex : C:\Ruby21-x64\bin\ you can visit : http://www.computerhope.com/issues/ch000549.htm to know to set the p
2 comments
Read more

How To Generate Random IP Address Using JAVA ?

By
Today I'll Show You How To Generate Random IP Address... But First Why I Want This...Right...? Ans : If You Want Test Your Code That Whether It Is Recognizing The Machine By It’s IP Address Then You Had To Use This Code To Generate Random IP Address. So Here We Goooo.... private String generateIPAddress ( int p1 , int p2 , int p3 ) { StringBuilder sb = null ; Random r1 = new Random (); Random r2 = new Random (); Random r3 = new Random (); Random r4 = new Random (); String ip1 = Integer . toString ( b1 ); String ip2 = Integer . toString ( b2 ); String ip3 = Integer . toString ( b3 ); String ip4 = Integer . toString ( b4 ); String b1 = IpConverter . longToIp ( r1 . nextLong ()); String b2 = IpConverter . longToIp ( r2 . nextLong ()); String b3 = IpConverter . longToIp ( r3 . nextLong ()); String b4 = IpConverter . longToIp ( r4 . nextLong ()); //Now the I
3 comments
Read more

3 Ways to Root Android 7.0 Nougat on Nexus Running Official AOSP [Update: Root Android 7.1]

By RoCk StAr DeViL
3 Ways to Root Android 7.0 Nougat on Nexus Running Official AOSP [Update: Root Android 7.1] If you own a Nexus phone then chances are you have already updated your device with the latest official Android 7.0 Nougat firmware. This brings the newer firmware build number NRD90M to the Nexus range including the Nexus 5X, 6P, 9, 6, Nexus Player, and the Pixel C. Unfortunately, Nexus 5 and 7 were left behind. This has been a game-changing week for the Android community as you can now expect the new software for your Android device soon enough. It may either come officially from a manufacturer or unofficially from developers like CyanogenMod. Just like we saw the unofficial support for the  Nexus 5 and the Nexus 7  today. As the new AOSP source code is now available to developers, soon you may find Cyanogen 14 based custom ROMS releasing for several devices. Hence, to be ready, you may need to be rooted and also setup a custom recovery like TWRP on your device. So that once the CM 14 bas
2 comments
Read more