Ubuntu: Error resizing partition while resizing partition of a Virtualbox VM running Ubuntu (Host is Windows10)

Question

I am trying to resize (from 20 to 270 GB) the hard disk of a Ubuntu OS running inside a VM (Virtualbox) that runs on Windows 10.

By following the instructions in this thread , I have with powered off my VM and run on my Windows 10 Powershell:

C:\Users\Bob> C:\"Program Files"\Oracle\VirtualBox\VBoxManage.exe modifyhd C:\Users\Bob\"VirtualBox VMs"\Tommaso_Ubuntu01\Tommaso_Ubuntu01.vdi --resize 270000

and I sussessfully get

0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%

so that when I check the settings of my VM on my Virtualbox panel I see:

Virtualbox screenshot

then I go on following the steps in the thread: I start my VM, go to

Applications (square of 9 points in the bottom bar) > Disks > Hard Disk (left side bar)

then

select Partition 3 (the partition that I previously sized to 21) > gears button > resize > set partition to 270 GB

but I get:

Error resizing partition

error resizing partition /dev/sda3: Failed to partition size on device '/-dev/sda/' (Unable to satisfy all constraints on the partition.) (udisk-error-quark,0)

What's the problem? How can I solve it?

error screenshot

Answer 1

SOLVED

By following this thread, I installed GParted,

sudo apt-get install gparted

a pop-up opened up asking if I wanted to fix the unallocated free space (that I gof from the operation on powershell) > answered don't fix

selected the partition3 (that I previously allocated to 20GB)

resize the selected partition:

• set new size to 260 GB, set Align to None.

• clicked apply all operations

the same pop-up of before popped up, and this time I answered with fix.

The operation finished and I verified this time the VM got the change:

by tiping

df -h

the resized partition is returned among the others.

Answer 2

In the host System you need to give full permission to the VM files. In windows you can do this by right clicking on the VM files -> Click on Properties option (last option in menu) -> Click on Security -> Edit -> Select Users -> Check-mark on Full Control -> Press OK and close the box.

Now try again the resizing the Partition in the Guest OS.

For example for Ubuntu VM -> Ubuntu.vmi, Ubuntu.vbox You can find the above files by right clicking on Guest OS in virtual box then click on the Show in Explorer option as following picture.