Dual-boot Windows 7 and Kali Linux

what is duel boot
Also called a multiboot, an operating system configuration that enables the user to boot the computer system from one of two different operating systems that are both installed on the same hard drive.

This article is a step-by-step guide on how to dual-boot Windows 7 and Kali Linux on a single hard disk drive (HDD). Kali Linux is  a distribution designed for penetration testing and security professionals. It ships with about 300 penetration testing and hacking applications installed
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While BackTrack is based on Ubuntu, Kali Linux is based on Debian, and uses the complete Debian Installer. As a result, the installation process is different from that of BackTrack, which uses Ubuntu’s graphical installation program.

The objective here is to show how to install it on an HDD alongside an existing installation of Windows 7, with the Windows 7 boot manager as the “master” boot loader, so that at the end, when the computer is (re)booted, you will be presented with a boot menu that looks just like the one shown below. Selecting Windows 7 boots the system into Windows 7 and choosing Kali Linux will, by default, take you to the Kali Linux boot menu, which is the same thing as the GRUB 2 menu, the version of GRUB used by Kali Linux.


To bypass Kali Linux’s boot menu, simply edit the file named /etc/default/grub and change GRUB_TIMEOUT=5 to GRUB_TIMEOUT=0. Then run the update-grub command.

Now that we know what to do, and what the result will be, let’s get it done. If you have not done so already, download an installation image of Kali Linux from here.
1. Shrink the Windows 7 C Drive: My test system has an existing installation of Windows 7 on a 500 GB HDD, with just two primary partitions. This is how they appear in Windows 7′s partition manager. The task here is to shrink the C drive to create room for installing Kali Linux. To do that, right-click on the C drive and select Shrink Volume.
Note: If you intend to install Windows 7 afresh, this process will be a lot easier if you set aside the free space that will be used for Kali Linux during the installation of Windows 7.

If you have enough free space on the C drive, the system will suggest a 50-50 split of the free space. Which is just good enough for this test installation. Shrink.

After the operation has completed, you should see the newly reclaimed space next to the C drive. You may exit the partition manager and reboot the computer. Be sure to have the installation disc of Kali Linux in the optical drive before rebooting.

2. Install Kali Linux: The best option to select on Kali Linux’s boot menu is Graphical Install. It gives you a point-and-click installation process. Install works just as well, but the interface is ncurses-based.

For installing Kali Linux, the following partitions will be created: /boot, /, /home, and Swap. In that order. The /home partition is optional. At the disk partitioning methods step of the installation process, you get a bunch of options. Because none of the guided options will create a separate /boot partition, creating the partitions will have to be done manually. So select “Manual” and click Continue.

Here you can see the existing Windows 7 partitions, both of which are primary partitions. The free space, reclaimed from Windows 7 in the previous step is what will be used for creating the partitions for Kali Linux. To start creating the partitions, select the free space and click Continue.

Create a new partition. Continue.

This shows the total amount of disk space available for Kali Linux. The /boot partition will be created first, so you need to specify the amount of disk space for it.

For this test system, I assigned 300 MB to it. Continue.

Because you still have two primary partitions to use, you can create the boot partition as a primary or logical partition. Either option will work, but the installer prefers creating it as a primary partition, if the boot loader is going to be installed in it. For this test installation, I chose to create it as a logical partition. Continue.

Beginning. Continue.

This step shows the details of the boot partition you just created. The only thing you need to change here is the mount point. Double-clicking on it will open another window where you can specify the correct mount point.

Here’s what it should look like after the mount point has been specified. The other option you might want to change here is the Bootable flag.

There is a good reason it should be enabled, but the system will boot even if it is disabled. It just depends on your BIOS version. For this test installation, it was disabled and the system still worked perfectly.

Here’s the final details of the boot partition. Scroll to “Done setting up the partition,” then click Continue. Note that the steps you used to create the boot partition will be repeated for the other partitions.

Back to the main disk partitioning window, you can see the boot partition you just created, plus the remaining free space. Select, the free space, then click Continue.


The next partition will be mounted at /. A new installation of Kali Linux takes up about 6.4 GB of disk space, so any amount greater than that will do. For the test installation, I gave it 60 GB, which is way too much, so you do not have to do the same. About 10-12 GB is more than enough. Continue.

Here are the details of the new partition. Scroll to “Done setting up the partition,” then click Continue.

For the home partition, I gave it a disk space of 100 GB. Continue.

Here are the details of the new partition. Scroll to “Done setting up the partition,” then click Continue.

For Swap, 2 GB is good enough. Continue.

Here are the default details of the new partition. To specify that it be used as a Swap partition, double-click the “Use as” line.

Then select “swap area.” Continue.

Scroll to “Done setting up the partition,” then click Continue.

With all the partitions created, scroll to “Finish partitioning and write changes to disk.” Continue. Make note of the device number of the boot partition. Here, it is sda5. You’ll need it later.

Select “Yes.” Continue.

By default, the installer will want to install GRUB, the boot loader, in the Master Boot Record (MBR). However, for setting up this dual-boot system, we want GRUB in the boot partition. So, select “No.” Continue.

This is where you have to specify where GRUB should be installed. For this test system, it is /dev/sda5. Continue.

After installation, the computer will reboot into Windows 7. The next task involves add an entry for Kali Linux in Windows 7′s boot menu.
3. Add Kali Linux to Windows 7′s boot menu: The simplest graphical application for modifying the Boot Configuration Data of Window that I know, is EasyBCD. It is free for personal use. You may download it from here. Install it as you would any other Windows application. The main window is shown below. To add an entry for Kali Linux in the boot menu, click on the Add New Entry tab.

Then click on the Linux/BSD tab. From the Type dropdown menu, select GRUB 2. Modify the name field to reflect the name of the distribution you are adding. From the Drive menu, you can either select the specific partition corresponding to the boot partition of the Kali Linux installation or let EasyBCD automatically locate and load it. Either one will work. Note that EasyBCD’s drive numbers and the device numbers of the Linux partitions do not match. For example, in this test installation, the boot partition is /dev/sda5, but the corresponding drive number in EasyBCD is Partition 3. The size of the partition helps to determine which one it is. Click the Add Entry button when wll the options have been specified.

From the Edit Boot Menu tab, you can see a preview of the entries that will appear in the Windows 7 boot menu. Exit EasyBCD and reboot the computer. That should do it.

Extra: Here are all the partitions on the HDD as seen from the Windows 7 partition manager.