<disk type='file' device='cdrom'>
<driver name='qemu' type='raw'/>
<source file='/data_ssd/iso-images/ubuntu-16.04.6-server-amd64.iso'/>
<target dev='hdc' bus='ide'/>
<readonly/>
<boot order='1'/>
<address type='drive' controller='0' bus='1' target='0' unit='0'/>
</disk>
<disk type='file' device='cdrom'>
<driver name='qemu' type='raw'/>
<target dev='hda' bus='ide'/>
<readonly/>
<address type='drive' controller='0' bus='0' target='0' unit='0'/>
</disk>