Comment 9 for bug 1728379

contrail-api-0.log during the failure: (from 10.102.28.116)
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Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/bottle.py", line 856, in _handle
    return route.call(**args)
  File "/usr/lib/python2.7/dist-packages/bottle.py", line 1721, in wrapper
    rv = callback(*a, **ka)
  File "/usr/lib/python2.7/dist-packages/vnc_openstack/context.py", line 37, in wrapper
    return fn(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/vnc_openstack/__init__.py", line 1073, in handler_trap_exception
    response = handler(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/vnc_openstack/neutron_plugin_interface.py", line 329, in plugin_http_post_subnet
    return self.plugin_create_subnet(context, subnet)
  File "/usr/lib/python2.7/dist-packages/vnc_openstack/neutron_plugin_interface.py", line 274, in plugin_create_subnet
    subnet_info = cfgdb.subnet_create(subnet['resource'])
  File "/usr/lib/python2.7/dist-packages/vnc_openstack/neutron_plugin_db.py", line 2712, in wrapper
    return func(self, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/vnc_openstack/neutron_plugin_db.py", line 3013, in subnet_create
    ipam_fq_name)
  File "/usr/lib/python2.7/dist-packages/vnc_openstack/neutron_plugin_db.py", line 1525, in _subnet_vnc_to_neutron
    sn_name = subnet_vnc.get_subnet_name()
AttributeError: 'NoneType' object has no attribute 'get_subnet_name'
97.0.0.17 - - [2017-10-31 08:33:01] "POST /neutron/subnet HTTP/1.1" 500 156 0.066508