qemu

To resize gcow2 image, run qemu-img resize FILE.qcow2 +10GB To create a gcow2 image, run qemu-img create -f qcow2 -o preallocation=metadata FILE.new 10G You can also use virt-resize –debug –expand /dev/vda1 FILE.qcow2 FILE.qcow2.new virt-resize is part of http://libguestfs.org