$ virsh attach-device guest-name device.xml
error: Failed to attach device from device.xml
error: cannot open file 'pool-name/volume-name': No such file or directory

$ cat device.xml
<disk type='network' device='disk'>
    <driver name='qemu' type='raw'/>
    <auth username="my-cephx-user">
        <secret type="ceph" uuid="00000000-0000-0000-0000-000000000000"/>
    </auth>
    <source protocol='rbd' name='pool-name/volume-name'>
        <host name="0.0.0.0" port="6789"/>
    </source>
    <target dev='vdb' bus='virtio'/>
</disk>