I've got Debian 10 XFCE installed to and running from a USB stick. Inside that I have two identical Debian minimal-install server VMs that run under QEMU/KVM behind NAT so that I can have the two talk to each other as a network inside the single computer. This for purposes of safely practicing and experimenting with things like SSH keys and WireGuard without external network or internet access. All, well and good; works great as long as I stick to the same computer and nic with which I created the VMs. The problem is that I have limited storage for snapshots and clones so that currently, if I screw something up or switch computers, experience indicates that I have to create new individual VMs by installing from scratch to start again clean. That takes a long time. So I'm thinking that before I waste too much more time reinventing the wheel every time I go 'round, that I ought to be able to copy clean unused images of my two VMs on another USB stick so that I can just conveniently delete and replace as required. First question: I ought to be able to create an elastically sized VM with QEMU/KVM in a manner similar to how dynamically allocated storage works in VirtualBox so that the image I copy across different USB sticks can be relatively small and quick to copy? Second question: At present I must copy via command line as root or with sudo as Thunar GUI file manager won't give me permission by any means I can discover. I'd like to use Thunar so I can get some visual feedback about copy progress. I ought to be able to run Thunar from the desktop as root somehow, right? As I write I *think* my old laptop with USB 2.0 is somewhere in the midst of copying an 8.0 GB image, but it keeps timing-out into lockscreen, and for all I know something has gone wrong. The USB sticks are warm as a cup of coffee, but the cursor in the terminal is just sitting there without blinking and it's all taking way too long: tom@debian10xfceUSB: /var/lib/libvirt/images$ sudo cp generic-2.qcow2 /media/tom/C58A-66EE/ All hints and advice are welcome. Thanks, Tom