Virtual disk and virtual drive are software components that emulate an actual disk storage device.

You may also connect the disk from Windows explorer by right-clicking the required image file with the.rdr extension and selecting Connect as Virtual Disk from the shortcut menu. If you select an image with incremental data backup, the Image Date/Time Selection panel will appear. A: All of the disk images that I provide on this website fall under the category of 'Abandonware,' meaning that they are over 7 years old, mostly out of use by the general populace and no longer supported by their respective manufacturers.

Virtual disks and virtual drives are common components of virtual machines in hardware virtualization, but they are also widely used for various purposes unrelated to virtualization, such as for the creation of logical disks.

Operation[edit]

A virtual drive is a software component that emulates an actual disk drive, such as an optical disc drive, a floppy disk drive, or a hard disk drive. To other programs, a virtual drive looks and behaves like an actual physical device.

A virtual disk image (VDI) is the image of a virtual hard disk or the logical disk associated with a virtual machine. It is used in virtualization environments to create a replica of the disk space/drive assigned to one or more virtual machines. Techopedia explains Virtual Disk Image (VDI). If you work with virtual machines, you know about virtual disk images where the files, the operating system, and other necessary data of a virtual machine is stored. That is what for, virtual disks are used by most people, however, you can even use a virtual disk to keep your important files, backups and a number of other items in a.

A virtual disk may be in any of the following forms:

Disk image, a computer file that contains the exact data structure of an actual storage device
Logical disk (also known as vdisk), an array of two or more actual drives that cooperatively act like a single device
RAM disk, which stores its data in random-access memory (RAM) instead of on a storage device
A mapped network drive that connects to a File Server

Uses[edit]

In hardware virtualization, virtual machines implement virtual drives as part of their efforts to emulate the behavior of an actual machine. As with an ordinary computer, a virtual machine needs one virtual drive and one disk image to start up, except when it is performing a network boot. More virtual drives are added as needed.

Virtual optical drives are used on physical computers to transfer the contents of the optical disks onto hard disk drives. Doing so helps in resolving the problem of the short life span of CDs and DVDs and takes advantage of the faster data transfer rate of hard disk drives. However, virtual optical drives are also used for software piracy: early computer games used disc existence verification to ensure licensed use, which can be circumvented using virtual optical drives. As a countermeasure, the StarForce copy protection scheme attempts to thwart disc virtualization. Modern video games have migrated to online product activation as part of their distribution process.

See also[edit]

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My 160GB hard disk is running out of free space. Seriously low… It’s amazing that I’ve managed to fill it up with so much stuff and it’s all work stuff too. Now normally I rebuild my laptop every 4 months or so (yes I really do) but this time, I don’t necessarily have the luxury of spending a couple of days because I’m up to my armpits on a project.

So my normal setup is to have my one physical disk partitioned into two: one for the native operating system and the other for my data. I’ve always favoured split partitions, since configuration means that if I ever need to do a rebuild, I don’t have to spend overnight backing up all my work data before the drive gets obliterated. Even though it only takes about 45-60minutes to reinstall Windows 7, it does take a while to install Microsoft Office, Visual Studio, SQL Server and a plethora of other programs and tools. It’s probably a couple of days before I’m comfortably back into a situation where everything is back to how I want it to be.

Thing is, I don’t have a couple of days and ultimately it’s not going to solve my space issue. So I have a cunning plan with Windows 7 because I’ve discovered that it’s now got the inbuilt capability that allows it to mount and boot from Virtual Hard Disks (VHDs). Effectively a portable, logical disk that runs natively on the hardware – not in a virtual machine.

Basically, a VHD is a large contiguous file structure that can be recognised as a hard disk, yet it’s a virtual one sitting on your physical hard disk. I can backup my existing physical disk partitions to a VHD but it has to sit on a larger disk than the original, because there is an amount of hidden space used by the operating system to host the file. VHD’s are a bit clever in that they can be setup as “dynamic” and expand as necessary when data is added to it – there is no compression involved, but the free space is squeezed out in an attempt to minimise the overall footprint of the VHD – a 160GB partition with 50% free space will result in a VHD file with a 80GB footprint. Alternatively, VHDs can be set to “fixed” and remain that size regardless of its mounted state – a 160GB VHD remains 160GB. If you want faster performance then select “fixed”, if you are scrimping on space then select “dynamic” but beware that someday you’ll need that full expanded space available if you fill it up!

So, after crooning after a range of Solid State Disks (SSDs) which are blisteringly fast, very expensive but ultimately too small in capacity, I decided to try a 500GB Seagate Momentus XT Solid State Hybrid Drive. Best of both worlds really, optimised for speed, not so expensive and big capacity. Rather ironic, that EMC is one of the largest disk suppliers yet we don’t put high performance disks in our consultancy laptops!

DISCLAIMER:
THIS IS MY JOURNEY FROM DISK TO VHD.
IF YOU FOLLOW ANY OF THESE STEPS, THEN YOU DO IT AT YOUR OWN RISK!

Creating your VHD

First thing to get your hands on is Disk2VHD. This is a neat little SysInternals tool from Microsoft (just recently had a revamp) which will create you a VHD file for use in Microsoft Virtual PC or for an Hyper-V virtual machine. Unlike some other tools out there, Disk2VHD can backup a disk/volume that is currently operational. YES, that means that you can transpose that disk/volume that you’ve currently booted from!

Download and install
Run “Disk to VHD converter” as administrator.
The following dialog will pop up, telling you what you can convert and how much space you need to complete the operation.
Specify a destination file name for your VHD.
Tick the partitions that you want to include into the VHD.
Click “Create” and the tool will take a snapshot and proceed to transfer data.
Depending on the sizes of the partitions you clicked, wait….

Couple of things to note:

If you are transferring relatively big partitions (>20GB) then be prepared to wait a while! When I Disk2VHD’ed my laptop, it estimated a 115GB VHD file so I left the tool running overnight!
Disk2VHD can backup your currently operational drive onto a disk in that archive – I could have cloned the C: and E: partitions to a file on the E: partition. BUT, for performance reasons, this is not optimal. Either plug in a spare USB hard disk or connect to a network drive.
Don’t think that you have to keep all your partitions on the same VHD. If you want to share a partition amongst different instances, then just backup the minimum to each VHD.
Only the booting VHD is guaranteed to be mounted on restart; additional VHDs need to be mounted manually or by script since Windows 7 will not remember on reboot.

With my 160GB laptop hard disk backed up to VHD on a network drive, I can now swap my old physical hard disk for my new shiny 500GB Seagate Momentus XT Solid State Hybrid Drive. I decided to con

Faqvirtual Disk Images