I am seeing the same Issue. I have libvirt version 1.2.2. Do we need a libvirt version higher than 1.2.2 for this change to work? 2015-09-18 01:30:29.723 ERROR nova.compute.manager [req-c5b00bd7-943b-44cd-847b-064286501d6a admin admin] [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] Instance failed to spaw n 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] Traceback (most recent call last): 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] File "/opt/stack/nova/nova/compute/manager.py", line 2152, in _build_resourc es 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] yield resources 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] File "/opt/stack/nova/nova/compute/manager.py", line 2006, in _build_and_run _instance 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] block_device_info=block_device_info) 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] File "/opt/stack/nova/nova/virt/libvirt/driver.py", line 2451, in spawn 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] block_device_info=block_device_info) 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] File "/opt/stack/nova/nova/virt/libvirt/driver.py", line 4522, in _create_do main_and_network 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] xml, pause=pause, power_on=power_on) 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] File "/opt/stack/nova/nova/virt/libvirt/driver.py", line 4452, in _create_do main 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] guest.launch(pause=pause) 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] File "/opt/stack/nova/nova/virt/libvirt/guest.py", line 141, in launch 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] self._encoded_xml, errors='ignore') 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] File "/usr/local/lib/python2.7/dist-packages/oslo_utils/excutils.py", line 1 95, in __exit__ 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] six.reraise(self.type_, self.value, self.tb) 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] File "/opt/stack/nova/nova/virt/libvirt/guest.py", line 136, in launch 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] return self._domain.createWithFlags(flags) 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] File "/usr/local/lib/python2.7/dist-packages/eventlet/tpool.py", line 183, i n doit 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] result = proxy_call(self._autowrap, f, *args, **kwargs) 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] File "/usr/local/lib/python2.7/dist-packages/eventlet/tpool.py", line 141, i n proxy_call 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] rv = execute(f, *args, **kwargs) 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] File "/usr/local/lib/python2.7/dist-packages/eventlet/tpool.py", line 122, i n execute 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] six.reraise(c, e, tb) 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] File "/usr/local/lib/python2.7/dist-packages/eventlet/tpool.py", line 80, in tworker 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] rv = meth(*args, **kwargs) 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] File "/usr/local/lib/python2.7/dist-packages/libvirt.py", line 900, in creat eWithFlags 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] if ret == -1: raise libvirtError ('virDomainCreateWithFlags() failed', dom=self) 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] libvirtError: unsupported configuration: scripts are not supported on interfaces of type bridge 2015-09-18 01:30:29.723 TRACE nova.compute.manager [instance: 6d9297cc-d97f-40f9-a504-a17b79d279a5] This variable is coming out to be an empty string for me "