openstack 网络创建问题 nova network-create

[root@controller openstack]# nova network-create demo-net --bridge br100 --multi-host T --fixed-range-v4 10.0.0.55/24

ERROR (ClientException): The server has either erred or is incapable of performing the requested operation. (HTTP 500) (Request-ID: req-28010de4-6872-4cab-bbbe-429b27fb67bd)

唯一的错误日志：

[root@controller log]# find . -name '*.log'|xargs grep -n 09:19|grep ERROR

./nova/nova-api.log:7:2015-10-27 09:19:49.529 8731 ERROR nova.api.openstack [req-28010de4-6872-4cab-bbbe-429b27fb67bd 9ab1d21010e349989f989d242baf514a 917bba0b8c9e4377933f414e8caeb12b - - -] Caught error: