Hi， I found you have a wrong configuration of "overlay_ip_version" from ml2_conf.ini, you can check it , it could config to "6" or "4". But I am not sure it is the reason for you problem. Thanks, Yun At 2019-08-14 19:16:22, "Zufar Dhiyaulhaq" <zufardhiyaulhaq@gmail.com> wrote: Hi everyone, I try to install OpenStack with OVN enabled. But when trying to start neutron-server, the service is always inactive (exited) I try to check neutron-server logs and gets this message: 2019-08-14 05:40:32.649 4223 INFO networking_ovn.ml2.qos_driver [-] Starting OVNQosDriver 2019-08-14 05:40:32.651 4224 INFO networking_ovn.ovsdb.impl_idl_ovn [-] Getting OvsdbSbOvnIdl for MaintenanceWorker with retry 2019-08-14 05:40:32.654 4225 INFO ovsdbapp.backend.ovs_idl.vlog [-] tcp:10.101.101.10:6641: connecting... 2019-08-14 05:40:32.655 4225 INFO ovsdbapp.backend.ovs_idl.vlog [-] tcp:10.101.101.10:6641: connected 2019-08-14 05:40:32.657 4220 INFO ovsdbapp.backend.ovs_idl.vlog [-] tcp:10.101.101.10:6642: connecting... 2019-08-14 05:40:32.658 4220 INFO ovsdbapp.backend.ovs_idl.vlog [-] tcp:10.101.101.10:6642: connected 2019-08-14 05:40:32.660 4225 INFO networking_ovn.ovsdb.impl_idl_ovn [-] Getting OvsdbSbOvnIdl for AllServicesNeutronWorker with retry 2019-08-14 05:40:32.670 4220 INFO neutron.wsgi [-] (4220) wsgi starting up on http://0.0.0.0:9696 2019-08-14 05:40:32.692 4225 INFO ovsdbapp.backend.ovs_idl.vlog [-] tcp:10.101.101.10:6642: connecting... 2019-08-14 05:40:32.692 4225 INFO ovsdbapp.backend.ovs_idl.vlog [-] tcp:10.101.101.10:6642: connected 2019-08-14 05:40:32.693 4224 INFO ovsdbapp.backend.ovs_idl.vlog [-] tcp:10.101.101.10:6642: connecting... 2019-08-14 05:40:32.694 4224 INFO ovsdbapp.backend.ovs_idl.vlog [-] tcp:10.101.101.10:6642: connected 2019-08-14 05:40:32.697 4224 INFO networking_ovn.ml2.qos_driver [-] Starting OVNQosDriver 2019-08-14 05:40:32.844 4225 INFO oslo_service.service [-] Parent process has died unexpectedly, exiting 2019-08-14 05:40:32.844 4224 INFO oslo_service.service [-] Parent process has died unexpectedly, exiting 2019-08-14 05:40:32.844 4222 INFO oslo_service.service [-] Parent process has died unexpectedly, exiting 2019-08-14 05:40:32.845 4223 INFO oslo_service.service [-] Parent process has died unexpectedly, exiting 2019-08-14 05:40:32.845 4221 INFO oslo_service.service [-] Parent process has died unexpectedly, exiting neutron-server full logs: https://paste.ubuntu.com/p/GHfS38KFCr/ ovsdb-server port is active: https://paste.ubuntu.com/p/MhgNs8SGdX/ neutron.conf and ml2_conf.ini: https://paste.ubuntu.com/p/4J7hTVf5qz/ Does anyone know why this error happens? Best Regards, Zufar Dhiyaulhaq