Hi Lucas,

Its always same, my OVSDB local instance is listening in unix:/var/run/openvswitch/db.sock

[root@zu-ovn-compute0 ~]#  ps ax | grep ovn-controller
15398 ?        S<s    0:00 ovn-controller unix:/var/run/openvswitch/db.sock -vconsole:emer -vsyslog:err -vfile:info --no-chdir --log-file=/var/log/openvswitch/ovn-controller.log --pidfile=/var/run/openvswitch/ovn-controller.pid --detach
15807 pts/0    S+     0:00 grep --color=auto ovn-controller

[root@zu-ovn-compute0 ~]#  grep ovsdb_connection /etc/neutron/plugins/networking-ovn/networking-ovn-metadata-agent.ini
ovsdb_connection = unix:/var/run/openvswitch/db.sock

[root@zu-ovn-compute0 ~]# tail -f /var/log/neutron/networking-ovn-metadata-agent.log

2019-08-16 10:29:08.391 15647 CRITICAL neutron [-] Unhandled error: Exception: Could not connect to unix:/var/run/openvswitch/db.sock
2019-08-16 10:29:08.391 15647 ERROR neutron Traceback (most recent call last):
2019-08-16 10:29:08.391 15647 ERROR neutron   File "/usr/bin/networking-ovn-metadata-agent", line 10, in <module>
2019-08-16 10:29:08.391 15647 ERROR neutron     sys.exit(main())
2019-08-16 10:29:08.391 15647 ERROR neutron   File "/usr/lib/python2.7/site-packages/networking_ovn/cmd/eventlet/agents/metadata.py", line 17, in main
2019-08-16 10:29:08.391 15647 ERROR neutron     metadata_agent.main()
2019-08-16 10:29:08.391 15647 ERROR neutron   File "/usr/lib/python2.7/site-packages/networking_ovn/agent/metadata_agent.py", line 38, in main
2019-08-16 10:29:08.391 15647 ERROR neutron     agt.start()
2019-08-16 10:29:08.391 15647 ERROR neutron   File "/usr/lib/python2.7/site-packages/networking_ovn/agent/metadata/agent.py", line 139, in start
2019-08-16 10:29:08.391 15647 ERROR neutron     self.ovs_idl = ovsdb.MetadataAgentOvsIdl().start()
2019-08-16 10:29:08.391 15647 ERROR neutron   File "/usr/lib/python2.7/site-packages/networking_ovn/agent/metadata/ovsdb.py", line 59, in start
2019-08-16 10:29:08.391 15647 ERROR neutron     'Open_vSwitch')
2019-08-16 10:29:08.391 15647 ERROR neutron   File "/usr/lib/python2.7/site-packages/ovsdbapp/backend/ovs_idl/idlutils.py", line 120, in get_schema_helper
2019-08-16 10:29:08.391 15647 ERROR neutron     raise Exception("Could not connect to %s" % connection)
2019-08-16 10:29:08.391 15647 ERROR neutron Exception: Could not connect to unix:/var/run/openvswitch/db.sock
2019-08-16 10:29:08.391 15647 ERROR neutron

[root@zu-ovn-compute0 ~]# systemctl status openvswitch
● openvswitch.service - Open vSwitch
   Loaded: loaded (/usr/lib/systemd/system/openvswitch.service; enabled; vendor preset: disabled)
   Active: active (exited) since Jum 2019-08-16 10:27:01 EDT; 4min 22s ago
 Main PID: 15323 (code=exited, status=0/SUCCESS)
    Tasks: 0
   CGroup: /system.slice/openvswitch.service

Agu 16 10:27:01 zu-ovn-compute0 systemd[1]: Starting Open vSwitch...
Agu 16 10:27:01 zu-ovn-compute0 systemd[1]: Started Open vSwitch.

[root@zu-ovn-compute0 ~]# systemctl status ovn-controller
● ovn-controller.service - OVN controller daemon
   Loaded: loaded (/usr/lib/systemd/system/ovn-controller.service; enabled; vendor preset: disabled)
   Active: active (running) since Jum 2019-08-16 10:27:12 EDT; 4min 22s ago
 Main PID: 15398 (ovn-controller)
    Tasks: 1
   CGroup: /system.slice/ovn-controller.service
           └─15398 ovn-controller unix:/var/run/openvswitch/db.sock -vconsole:emer -vsyslog:err -vfile:info --no-chdir --log-file=/var/log/openvswitch/ovn-controller...

Agu 16 10:27:12 zu-ovn-compute0 systemd[1]: Starting OVN controller daemon...
Agu 16 10:27:12 zu-ovn-compute0 ovn-ctl[15386]: Starting ovn-controller [  OK  ]
Agu 16 10:27:12 zu-ovn-compute0 systemd[1]: Started OVN controller daemon.