The cinder-volume is set for 20G, which is too small. the problem was encountered running the onap_openstack.yaml heat template, installing ONAP on open stack. The servers in the lab each have a 450G disk. Perhaps 200G is a better number?
The file in which this shows up is:
The parameter is loopback_device_size:
...set to 20 now. Perhaps 200 or 250.