neutron-openvswitch-agent 服务启动失败

1.openvswitch-agent.log日志报错信息，重启neutron-openvswitch-agent服务成功，但是服务状态无法启动。

2019-06-13 12:30:22.510 4208 INFO neutron.agent.securitygroups_rpc [req-8edf01ca-a3fc-43c6-bdce-44083eb1a518 - - - - -] Refresh firewall rules
2019-06-13 12:30:22.646 4208 INFO neutron.plugins.ml2.drivers.openvswitch.agent.ovs_neutron_agent [req-8edf01ca-a3fc-43c6-bdce-44083eb1a518 - - - - -] Configuration for devices up [] and devices down [] complet
ed.
2019-06-13 12:30:49.938 4208 INFO neutron.plugins.ml2.drivers.openvswitch.agent.ovs_neutron_agent [req-8edf01ca-a3fc-43c6-bdce-44083eb1a518 - - - - -] Agent caught SIGTERM, quitting daemon loop.
2019-06-13 12:30:50.049 4208 ERROR neutron.agent.linux.async_process [-] Error received from [ovsdb-client monitor Interface name,ofport,external_ids --format=json]: None
2019-06-13 12:30:50.049 4208 ERROR neutron.agent.linux.async_process [-] Process [ovsdb-client monitor Interface name,ofport,external_ids --format=json] dies due to the error: None
2019-06-13 12:30:50.060 4208 INFO oslo_rootwrap.client [req-8edf01ca-a3fc-43c6-bdce-44083eb1a518 - - - - -] Stopping rootwrap daemon process with pid=4241
2019-06-13 12:30:51.791 8239 INFO neutron.common.config [-] Logging enabled!
2019-06-13 12:30:51.792 8239 INFO neutron.common.config [-] /usr/bin/neutron-openvswitch-agent version 8.1.2
2019-06-13 12:30:51.800 8239 WARNING oslo_config.cfg [-] Option "prevent_arp_spoofing" from group "AGENT" is deprecated for removal.  Its value may be silently ignored in the future.
2019-06-13 12:30:51.924 8239 INFO oslo_rootwrap.client [-] Spawned new rootwrap daemon process with pid=8279
2019-06-13 12:30:52.013 8239 INFO neutron.plugins.ml2.drivers.openvswitch.agent.ovs_neutron_agent [req-f04c0a10-18f2-45d1-93d7-6056f75a81f2 - - - - -] Mapping physical network physnet1 to bridge br-ex
2019-06-13 12:30:52.124 8239 INFO neutron.agent.l2.extensions.manager [req-f04c0a10-18f2-45d1-93d7-6056f75a81f2 - - - - -] Loaded agent extensions: []
2019-06-13 12:30:52.256 8239 INFO neutron.plugins.ml2.drivers.openvswitch.agent.ovs_dvr_neutron_agent [req-f04c0a10-18f2-45d1-93d7-6056f75a81f2 - - - - -] L2 Agent operating in DVR Mode with MAC fa:16:3f:d9:0a:
54
2019-06-13 12:30:52.519 8239 INFO neutron.plugins.ml2.drivers.openvswitch.agent.ovs_neutron_agent [-] Agent has just been revived. Doing a full sync.
2019-06-13 12:30:52.753 8239 CRITICAL neutron [req-f04c0a10-18f2-45d1-93d7-6056f75a81f2 - - - - -] KeyError: 6
2019-06-13 12:30:52.753 8239 ERROR neutron Traceback (most recent call last):
2019-06-13 12:30:52.753 8239 ERROR neutron   File "/usr/bin/neutron-openvswitch-agent", line 10, in <module>
2019-06-13 12:30:52.753 8239 ERROR neutron     sys.exit(main())
2019-06-13 12:30:52.753 8239 ERROR neutron   File "/usr/lib/python2.7/site-packages/neutron/cmd/eventlet/plugins/ovs_neutron_agent.py", line 20, in main
2019-06-13 12:30:52.753 8239 ERROR neutron     agent_main.main()
2019-06-13 12:30:52.753 8239 ERROR neutron   File "/usr/lib/python2.7/site-packages/neutron/plugins/ml2/drivers/openvswitch/agent/main.py", line 49, in main
2019-06-13 12:30:52.753 8239 ERROR neutron     mod.main()
2019-06-13 12:30:52.753 8239 ERROR neutron   File "/usr/lib/python2.7/site-packages/neutron/plugins/ml2/drivers/openvswitch/agent/openflow/ovs_ofctl/main.py", line 36, in main
2019-06-13 12:30:52.753 8239 ERROR neutron     ovs_neutron_agent.