'Table 'ovn_revision_numbers' is already defined for this MetaData instance

[Arkadi Poliakevitch]

neutron-server logs an error when starting with OVN plugin enabled:

2021-03-27 11:53:02.660 828835 CRITICAL neutron.plugins.ml2.managers [-] The 'EntryPoint(name='ovn', value='neutron.plugins.ml2.drivers.ovn.mech_driver.mech_driver:OVNMechanismDriver', group='neutron.ml2.mechanism_drivers')' entrypoint could not be loaded for the following reason: 'Table 'ovn_revision_numbers' is already defined for this MetaData instance. Specify 'extend_existing=True' to redefine options and columns on an existing Table object.'.: sqlalchemy.exc.InvalidRequestError: Table 'ovn_revision_numbers' is already defined for this MetaData instance. Specify 'extend_existing=True' to redefine options and columns on an existing Table object.

Fresh install of Victoria openstack using Ubuntu Focal packages. Installed OVN:

apt install ovn-central
ovn-nbctl set-connection ptcp:6641:10.230.185.137 -- set connection . inactivity_probe=60000
ovn-sbctl set-connection ptcp:6642:10.230.185.137 -- set connection . inactivity_probe=60000
service ovn-northd restart
service ovn-ovsdb-server-nb.service start
service ovn-ovsdb-server-sb.service start

ovn-sbctl show

Chassis "3c63ed00-56ea-403e-8dad-adee06b2315f"
    hostname: o3p-os-compute-1.oppp.lab
    Encap geneve
        ip: "10.230.185.136"
        options: {csum="true"}

Configured neutron with ovn plugin:

vi /etc/neutron/neutron.conf
[DEFAULT]
core_plugin = neutron.plugins.ml2.plugin.Ml2Plugin
service_plugins = networking_ovn.l3.l3_ovn.OVNL3RouterPlugin

vi /etc/neutron/plugins/ml2/ml2_conf.ini
[ml2]
type_drivers = local,flat,vlan,geneve
tenant_network_types = geneve
overlay_ip_version = 4
mechanism_drivers = ovn
extension_drivers = port_security

[ml2_type_geneve]
vni_ranges = 1:65536
max_header_size = 38

[securitygroup]
enable_ipset = true
enable_security_group = true

[ovn]
ovn_nb_connection = tcp:10.230.185.137:6641
ovn_sb_connection = tcp:10.230.185.137:6642
ovn_l3_scheduler = leastloaded #other option is chance

service neutron-server restart

[Arkadi Poliakevitch (arkadipol)]

Sorry, followed old install guide (netwokring-ovn) instead of neutron. This can be closed as invalid.

[Lajos Katona (lajos-katona)]

Thanks for the comment