Comment 9 for bug 1602357

Saw what appears to be this issue in stable/rocky - may be related to Matt's comment above:

http://logs.openstack.org/48/638348/1/gate/heat-functional-convg-mysql-lbaasv2-py35/9d70590/logs/screen-n-api.txt.gz?level=ERROR

ERROR nova.api.openstack.wsgi [None req-e05ce059-71c4-437d-91e0-e4bc896acca6 demo demo] Unexpected exception in API method: nova.exception_Remote.VirtualInterfaceCreateException_Remote: Virtual Interface creation failed
pymysql.err.IntegrityError: (1062, "Duplicate entry 'fa:16:3e:9d:18:a6/aac0ca83-b3d2-4b28-ab15-de2d3a3e6e16-0' for key 'uniq_virtual_interfaces0address0deleted'")
oslo_db.exception.DBDuplicateEntry: (pymysql.err.IntegrityError) (1062, "Duplicate entry 'fa:16:3e:9d:18:a6/aac0ca83-b3d2-4b28-ab15-de2d3a3e6e16-0' for key 'uniq_virtual_interfaces0address0deleted'") [SQL: 'INSERT INTO virtual_interfaces (created_at, updated_at, deleted_at, deleted, address, network_id, instance_uuid, uuid, tag) VALUES (%(created_at)s, %(updated_at)s, %(deleted_at)s, %(deleted)s, %(address)s, %(network_id)s, %(instance_uuid)s, %(uuid)s, %(tag)s)'] [parameters: {'created_at': datetime.datetime(2019, 3, 20, 16, 11, 27, 753079), 'tag': None, 'uuid': 'aac0ca83-b3d2-4b28-ab15-de2d3a3e6e16', 'deleted_at': None, 'deleted': 0, 'address': 'fa:16:3e:9d:18:a6/aac0ca83-b3d2-4b28-ab15-de2d3a3e6e16', 'network_id': None, 'instance_uuid': '890675f9-3a1e-4a07-8bed-8648cea9fbb9', 'updated_at': None}] (Background on this error at: http://sqlalche.me/e/gkpj)

(This sequence of exceptions occurs 3 times, I assume because retrying is normally sufficient to fix a duplicate entry problem.)

The test was heat_integrationtests.functional.test_cancel_update.CancelUpdateTest.test_cancel_update_server_with_port