fantasy-639115_1920Virtualisation can be a strange world, but one worth exploring. It makes administering software environments and testing various setups much easier, you can quickly go back to a point in time before you messed up! However, this means you will be using snapshots within the Oracle VirtualBox environment. If like me, you quickly ran out of disk space then I learnt a lesson – expand the snapshot, not the base image.

Lookup the modifyhd command and you will see it is easy to extend a base disk size that you are using in your virtual machine:-

VBoxManage modifyhd “/Users/David/VirtualBox VMs/Win 8/Win 8.vdi” –resize 40000

That was easy, but on starting the virtual image, you will see under storage that the .vdi disk has been extended but on viewing the disk in the Windows Disk Management utility the extra space does not appear. After much hunting the Oracle forums and documentation I see that you need to extend the latest snapshot, not the original vdi file.

To do this run  VBoxManage showvminfo “Win 8” where “Win 8” is the name of my VirtualBox machine. 

You should see the name of the snapshot file /Users/David/VirtualBox VMs/Win 8/Snapshots/{3130a83a-4381-485e-81e8-b4d3d268a503}.vdi

Now use this file name in the modifyhd command  VBoxManage modifyhd “/Users/David/VirtualBox VMs/Win 8/Snapshots/{3130a83a-4381-485e-81e8-b4d3d268a503}.vdi” –resize 40000

Easy really – well it took a lot of hunting so thought it was worthwhile documenting.

Once the extra disk space is available within the OS to extend partition to use extra unallocated space,  On Windows use Disk Management utility