Here is the test failure seen:

ft71.90: networking_cisco.tests.unit.ml2.drivers.cisco.nexus.test_cisco_mech.TestCiscoPortsV2.test_nexus_vxlan_bind_port_StringException: Empty attachments:
  stderr
  stdout

pythonlogging:'': {{{
WARNING [neutron.agent.securitygroups_rpc] Driver configuration doesn't match with enable_security_group
 WARNING [neutron.api.extensions] Extension auto-allocated-topology not supported by any of loaded plugins
 WARNING [neutron.api.extensions] Extension bgp not supported by any of loaded plugins
 WARNING [neutron.api.extensions] Extension bgp_dragent_scheduler not supported by any of loaded plugins
 WARNING [neutron.api.extensions] Extension dvr not supported by any of loaded plugins
 WARNING [neutron.api.extensions] Extension extraroute not supported by any of loaded plugins
 WARNING [neutron.api.extensions] Extension flavors not supported by any of loaded plugins
 WARNING [neutron.api.extensions] Extension ext-gw-mode not supported by any of loaded plugins
 WARNING [neutron.api.extensions] Extension l3-ha not supported by any of loaded plugins
 WARNING [neutron.api.extensions] Extension l3_agent_scheduler not supported by any of loaded plugins
 WARNING [neutron.api.extensions] Extension metering not supported by any of loaded plugins
 WARNING [neutron.api.extensions] Extension port-security not supported by any of loaded plugins
 WARNING [neutron.api.extensions] Extension qos not supported by any of loaded plugins
 WARNING [neutron.api.extensions] Extension router_availability_zone not supported by any of loaded plugins
 WARNING [neutron.api.extensions] Extension router-service-type not supported by any of loaded plugins
 WARNING [neutron.api.extensions] Extension service-type not supported by any of loaded plugins
 WARNING [neutron.api.extensions] Extension vlan-transparent not supported by any of loaded plugins
   ERROR [neutron.api.extensions] Extension path 'neutron/tests/unit/extensions' doesn't exist!
 WARNING [neutron.quota.resource_registry] subnet is already registered
 WARNING [neutron.quota.resource_registry] subnetpool is already registered
 WARNING [neutron.quota.resource_registry] network is already registered
 WARNING [neutron.quota.resource_registry] port is already registered
 WARNING [neutron.scheduler.dhcp_agent_scheduler] No more DHCP agents
 WARNING [neutron.api.rpc.agentnotifiers.dhcp_rpc_agent_api] Unable to schedule network ef607857-766a-44a6-a21c-de3b5817243c: no agents available; will retry on subsequent port and subnet creation events.
 WARNING [neutron.scheduler.dhcp_agent_scheduler] No more DHCP agents
 WARNING [neutron.api.rpc.agentnotifiers.dhcp_rpc_agent_api] Unable to schedule network ef607857-766a-44a6-a21c-de3b5817243c: no agents available; will retry on subsequent port and subnet creation events.
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
   ERROR [neutron.plugins.ml2.managers] Failed to bind port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on host testhost
 WARNING [neutron.plugins.ml2.plugin] In _notify_port_updated(), no bound segment for port 4a63c58f-0e9b-4252-ae3d-4c59440b0aff on network ef607857-766a-44a6-a21c-de3b5817243c
}}}

Traceback (most recent call last):
  File "networking_cisco/tests/unit/ml2/drivers/cisco/nexus/test_cisco_mech.py", line 928, in test_nexus_vxlan_bind_port
    [expected_dynamic_segment])
  File "/home/jenkins/workspace/gate-networking-cisco-python27/.tox/py27/local/lib/python2.7/site-packages/mock/mock.py", line 947, in assert_called_once_with
    raise AssertionError(msg)
AssertionError: Expected 'continue_binding' to be called once. Called 10 times.