Steps to add disk in the Virtual Box of window machine
1. Open the Virtual box software and add disk by click on Setting button.
2. After open Setting, go to Storage tab in left panel and click + button on right panel above the list of already mapped storage.
3. Select Create button on new window.
4. Create the new harddisk by clicking CREATE button
5. Follow create harddisk button. Choose type as VDI and press next
5. Choose dynamic or fixed size disk
6. Choose size of disk.
7. Choose created disk for associate with the Virtual machine.
8. Now hard disk is listed with Virtual machine storage.
9. Now Start the Virtual machine and map your harddisk with the machine.
Linux use fdisk command – fdisk -l list the drives , format the disk
window use Disk Management –> First intialize then format the disk