qcow2-no-source.xml

<volume>
  <name>OtherDemo.img</name>
  <key>/var/lib/libvirt/images/OtherDemo.img</key>
  <capacity unit="G">5</capacity>
  <allocation>294912</allocation>
  <physical unit="G">5</physical>
  <target>
    <path>/var/lib/libvirt/images/OtherDemo.img</path>
    <format type='qcow2'/>
    <permissions>
      <mode>0644</mode>
      <owner>0</owner>
      <group>0</group>
      <label>unconfined_u:object_r:virt_image_t:s0</label>
    </permissions>
    <encryption format='qcow'>
      <secret type='passphrase' uuid='e78d4b51-a2af-485f-b0f5-afca709a80f4'/>
    </encryption>
  </target>
  <backingStore>
    <path>/dev/null</path>
    <format type='raw'/>
    <permissions>
      <mode>0644</mode>
      <owner>0</owner>
      <group>0</group>
      <label>unconfined_u:object_r:virt_image_t:s0</label>
    </permissions>
  </backingStore>
</volume>