AssertionError 'assert new_subnets' in Calico DHCP agent

[Nell Jerram]

During the CI run at http://logs.openstack.org/00/434000/2/check/gate-tempest-dsvm-networking-calico/3043239/logs/screen-calico-dhcp.txt.gz#_2017-02-15_01_39_49_625, the DHCP agent hit:

2017-02-15 02:08:06.146 4025 ERROR neutron Traceback (most recent call last):
2017-02-15 02:08:06.146 4025 ERROR neutron File "/usr/local/bin/calico-dhcp-agent", line 11, in <module>
2017-02-15 02:08:06.146 4025 ERROR neutron sys.exit(main())
2017-02-15 02:08:06.146 4025 ERROR neutron File "/usr/local/lib/python2.7/dist-packages/networking_calico/agent/dhcp_agent.py", line 648, in main
2017-02-15 02:08:06.146 4025 ERROR neutron agent.run()
2017-02-15 02:08:06.146 4025 ERROR neutron File "/usr/local/lib/python2.7/dist-packages/osprofiler/profiler.py", line 153, in wrapper
2017-02-15 02:08:06.146 4025 ERROR neutron return f(*args, **kwargs)
2017-02-15 02:08:06.146 4025 ERROR neutron File "/usr/local/lib/python2.7/dist-packages/networking_calico/agent/dhcp_agent.py", line 614, in run
2017-02-15 02:08:06.146 4025 ERROR neutron self.etcd.loop()
2017-02-15 02:08:06.146 4025 ERROR neutron File "/usr/local/lib/python2.7/dist-packages/networking_calico/logutils.py", line 21, in wrapped
2017-02-15 02:08:06.146 4025 ERROR neutron return fn(*args, **kwargs)
2017-02-15 02:08:06.146 4025 ERROR neutron File "/usr/local/lib/python2.7/dist-packages/networking_calico/etcdutils.py", line 252, in loop
2017-02-15 02:08:06.146 4025 ERROR neutron self.dispatcher.handle_event(response)
2017-02-15 02:08:06.146 4025 ERROR neutron File "/usr/local/lib/python2.7/dist-packages/networking_calico/etcdutils.py", line 82, in handle_event
2017-02-15 02:08:06.146 4025 ERROR neutron self._handle(key_parts, response, self.handler_root, {})
2017-02-15 02:08:06.146 4025 ERROR neutron File "/usr/local/lib/python2.7/dist-packages/networking_calico/etcdutils.py", line 100, in _handle
2017-02-15 02:08:06.146 4025 ERROR neutron handler_node[action](response, **captures)
2017-02-15 02:08:06.146 4025 ERROR neutron File "/usr/local/lib/python2.7/dist-packages/networking_calico/agent/dhcp_agent.py", line 290, in on_endpoint_set
2017-02-15 02:08:06.146 4025 ERROR neutron port['network_id'] = self._ensure_net_and_subnets(port)
2017-02-15 02:08:06.146 4025 ERROR neutron File "/usr/local/lib/python2.7/dist-packages/networking_calico/agent/dhcp_agent.py", line 355, in _ensure_net_and_subnets
2017-02-15 02:08:06.146 4025 ERROR neutron assert new_subnets
2017-02-15 02:08:06.146 4025 ERROR neutron AssertionError

[Nell Jerram (neil-jerram)]

This has clearly now been fixed. Given the age of the bug, I don't think it's worth digging up the detail of how that happened.