Sachin, we have seen this issue one more time today in the same control node:


2017-10-30 10:59:34.814 27662 DEBUG neutron.api.v2.base [req-d2e3cd05-177b-47b7-bdca-2241fafe5ba0 d48614806c614c6186c8a447772a5421 dfbaf5a8ab774ee89c34cd9e2a64ef32 - - -] Request body: {u'subnet': {u'name': u'jd28148-corp-site-jd28148-corp-site-subnet0-jz3nmebr7fhz', u'enable_dhcp': True, u'network_id': u'a7f4c1a2-4443-4f86-8f5e-9a262e405bab', u'dns_nameservers': [], u'ip_version': 4, u'cidr': u'28.148.0.0/24'}} prepare_request_body /usr/lib/python2.7/dist-packages/neutron/api/v2/base.py:662
2017-10-30 10:59:34.816 27662 INFO neutron.quota [req-d2e3cd05-177b-47b7-bdca-2241fafe5ba0 d48614806c614c6186c8a447772a5421 dfbaf5a8ab774ee89c34cd9e2a64ef32 - - -] Loaded quota_driver: <neutron_plugin_contrail.plugins.opencontrail.quota.driver.QuotaDriver object at 0x7f3015561e10>.
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource [req-d2e3cd05-177b-47b7-bdca-2241fafe5ba0 d48614806c614c6186c8a447772a5421 dfbaf5a8ab774ee89c34cd9e2a64ef32 - - -] create failed
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource Traceback (most recent call last):
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource   File "/usr/lib/python2.7/dist-packages/neutron/api/v2/resource.py", line 84, in resource
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource     result = method(request=request, **args)
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource   File "/usr/lib/python2.7/dist-packages/neutron/api/v2/base.py", line 410, in create
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource     return self._create(request, body, **kwargs)
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource   File "/usr/lib/python2.7/dist-packages/oslo_db/api.py", line 148, in wrapper
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource     ectxt.value = e.inner_exc
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource   File "/usr/lib/python2.7/dist-packages/oslo_utils/excutils.py", line 220, in __exit__
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource     self.force_reraise()
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource   File "/usr/lib/python2.7/dist-packages/oslo_utils/excutils.py", line 196, in force_reraise
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource     six.reraise(self.type_, self.value, self.tb)
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource   File "/usr/lib/python2.7/dist-packages/oslo_db/api.py", line 138, in wrapper
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource     return f(*args, **kwargs)
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource   File "/usr/lib/python2.7/dist-packages/neutron/api/v2/base.py", line 521, in _create
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource     obj = do_create(body)
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource   File "/usr/lib/python2.7/dist-packages/neutron/api/v2/base.py", line 503, in do_create
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource     request.context, reservation.reservation_id)
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource   File "/usr/lib/python2.7/dist-packages/oslo_utils/excutils.py", line 220, in __exit__
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource     self.force_reraise()
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource   File "/usr/lib/python2.7/dist-packages/oslo_utils/excutils.py", line 196, in force_reraise
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource     six.reraise(self.type_, self.value, self.tb)
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource   File "/usr/lib/python2.7/dist-packages/neutron/api/v2/base.py", line 496, in do_create
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource     return obj_creator(request.context, **kwargs)
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource   File "/usr/lib/python2.7/dist-packages/neutron_plugin_contrail/plugins/opencontrail/contrail_plugin_base.py", line 276, in create_subnet
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource     subnet_created = self._create_resource('subnet', context, subnet)
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource   File "/usr/lib/python2.7/dist-packages/neutron_plugin_contrail/plugins/opencontrail/contrail_plugin.py", line 286, in _create_resource
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource     obj_name=res_type)
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource   File "/usr/lib/python2.7/dist-packages/neutron_plugin_contrail/plugins/opencontrail/contrail_plugin.py", line 256, in _transform_response
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource     plugin_base._raise_contrail_error(info, obj_name)
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource   File "/usr/lib/python2.7/dist-packages/neutron_plugin_contrail/plugins/opencontrail/contrail_plugin_base.py", line 111, in _raise_contrail_error
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource     raise exc.NeutronException(**info)
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource NeutronException: An unknown exception occurred.
2017-10-30 10:59:34.893 27662 ERROR neutron.api.v2.resource



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This issue will block COX deployment.