Spanned Volume : Concept & Practical Implementation

A spanned volume is a formatted partition in which data is stored on more than one hard disk, yet it appears as one volume. Spanned volumes are a non-RAID drive architecture.

Drawback - Unlike RAID, spanned volumes have no fault-tolerance, so if any disk fails, the data on the whole volume could be lost.

Practical

Note - As we are working with Virtual Machine, so hard disk creation part is equivalent to attaching extra physical hard disks practically.

Steps
Attach two Hard Disks as HD1 and HD2 in Windows Server 2008 Click here to know how to add Hard Disk in Virtual Machine and Start the machine.


Start -> Control Panel -> Administrative Tools
Double Click on Computer Management
Select Disk Management
OK

Right Click on Disk 1 and Select New Spanned Volume

Next -> Add both the Disks and Specify their size in MB (I have specified 50 MB each)

Next -> Check Perform Quick Format -Next -> Finish
A warning will appear, give it yes.
You will find the New Volume N is created.

Now open My Computer. Here it will be shown as a single drive of size 100 MB

Create some folders and files in this new drive and shut down the machine.

Remove any one of the newly added hard disk from the machine. Click here to know How to remove a Hard Disk in Oracle VM VirtualBox and start the machine again.

Go to My Computer. Oh ! The New Volume (N:) is missing where we have stored some data.

Now 

Start -> Control Panel -> Administrative Tools

Double Click on Computer Management

Under the Storage node, Select Disk Management

It will look like this.

The disk spanning has failed as we have removed a disk out of it.

Right Click on Disk 1 and select Delete Volume. Yes.

Conclusion: 

In spanned volume. We were unable to recover the data lost due to the removal of hard disk from the machine.