Resizing a virtual disk in VirtualBox 4
As of VirtualBox version 4 resizing a virtual disk is now a simple task. Use the following command to resize the disk when the virtual machine is turned off:
VBoxManage modifyhd yourvmdisk.vdi --resize 3000
The size specified in the above command is in megabytes.
Before resizing, any snapshots on the disk will need to be removed, otherwise the disk size information will not be updated correctly.
Last updated: 09/03/2013