[ubuntu] How to clone a VM on KVM

Hi all,

Host - Ubuntu 16.04 Gnome desktop
VM - Ubuntu 16.04 Gnome desktop
KVM

On VM to be cloned -> right click
-> Clone

Clone virtual machine
Storage vm (No write access)
-> Detail
"create a new disk (clone) for the virtual machine" greyout

I have checked the VM to be cloned
"show virtual hardware detail"
It seems no item related.

According to following document it seems a little bid complicate to me for cloning a VM
How To Clone and Use KVM Virtual Machine in Linux
https://computingforgeeks.com/how-to...hine-in-linux/

Please help

Edit
===
If start virt-manager as root

grey disappears. Can I clone VM in this way?

Regards
satimis