Enlarging a VirtualBox VDI virtual disk
Published on 20th December 2018 Estimated Reading Time: 2 minutesIt is remarkable how the Windows folder manages to grow on your C drive, and one in a Windows 7 installation was the cause of my needing to expand the VirtualBox virtual machine VDI disk on which it was installed. After trying various ways to cut down the size, an enlargement could not be avoided. In all of this, it was handy that I had a recent backup for restoration after any damage.
The same thing meant that I could resort to enlarging the VDI file with more peace of mind than otherwise might have been the case. This needed use of the command line once the VM was shut down. The form of the command that I used was the following:
VBoxManage modifyhd <filepath/filename>.vdi --resize 102400
It appears that this also would work on a Windows host, but mine was Linux, and it did what I needed. The next step was to attach it to an Ubuntu VM and use GParted to expand the main partition to fill the newly available space. That does not mean that it takes up 100 GiB on my system just yet because these things can be left to grow over time and there is a way to shrink them too if you ever need to do just that. As ever, having a backup made before any such operation may have its uses if anything goes awry.