<disk type='file' device='disk'>
  <driver name='qemu' type='qcow2'/>
  <source file='/var/lib/libvirt/images/rhel7.3.1507297895'>
    <privateData>
      <nodenames>
        <nodename type='storage' name='#block004'/>
        <nodename type='format' name='#block126'/>
      </nodenames>
    </privateData>
  </source>
  <backingStore type='file' index='1'>
    <format type='qcow2'/>
    <source file='/var/lib/libvirt/images/rhel7.3.1484071872'>
      <privateData>
        <nodenames>
          <nodename type='storage' name='#block256'/>
          <nodename type='format' name='#block313'/>
        </nodenames>
      </privateData>
    </source>
  </backingStore>
  <target dev='vda' bus='virtio'/>
  <alias name='virtio-disk0'/>
</disk>