Partitioning the disk

Partition of the hard disk (whether virtual or physical) involves splitting the drive into logical drives. Think of it as having a large apartment studio comprising one large room. Now imagine that you've put up a wall to separate the apartment in half. It's still physically one apartment, but now it's separated into two rooms. One can be used as the main apartment and the other as storage, or you can even have two smaller apartments to share with yourself and a friend. Equally, a partition can allow for the installation of multiple operating systems on a hard disk, or even create additional volumes to use as storage space.

Continuing with our Kali Linux installation, the next step provides options on the usage of the virtual disk for partitioning. As this is a virtual disk, I recommend using the Guided - use entire disk partitioning method. This method is very simple, and uses all available allocated space assigned to the virtual disk in the preceding steps. Firstly, let's select the recommended partitioning method:

The other options in the screenshot above, present the user with options for setting up LVM (Logical Volume Manager) and encrypted LVM. The LVM manages logical partitions and can create, resize and delete Linux partitions.

The prompt warns that all data (if any) on the disk will be erased if choosing this option; however, this is a new virtual disk with no existing data on it, so we can continue with our installation.

After selecting the VirtualBox disk as seen in the following screenshot, be sure to select All files in one partition:

As we continue the partitioning process, one of the main reasons I've recommended the guided partition option is because it does almost everything for us. From here, we simply choose the last available option, which says Finish partitioning and write changes to disk, followed by clicking Continue:

The last step in the partitioning process asks for confirmation to write the specified configurations and changes to the disk. Be sure to choose Yes before clicking on Continue:

We're now just a few clicks away from having our Kali Linux VM installed and operational.

After the installation is complete, the Package Manager prompts to choose a network mirror, which allows us access to newer versions of the software. I'd advise skipping this step by clicking on No, as we will soon be installing our updates for Kali manually once we're up and running.

One of the last steps to take in the installation process is to Install the GRUB boot loader on a hard disk. Without going into too much detail, the GRUB (GRand Unified Bootloader) allows for a multiboot environment by allowing the user to safely have and choose between operating systems at boot screen, preserving the boot entries for each installed OS.

Although we can choose not to install GRUB (as we only have one OS installed on our virtual hard disk), the Yes option should be chosen if dual or multibooting with other OSes:

If choosing Yes to install GRUB, be sure to select the bootable device:

After clicking on Continue, the installation completes and boots into Kali Linux.