Generally, after installing keystone, glance, nova services, you have to create a corresponding database in MySQL (usually the databases are created manually). But neutron service doesn’t require that, as the service will populate the database automatically. However, it didn’t behave that way and we had to manually run ‘neutron-db-manage‘ before starting ‘neutron-server’.
Execute the below commands to configure the network plugins
$openstack-config --set /etc/neutron/neutron.conf DEFAULT core_plugin neutron.plugins.ml2.plugin.Ml2Plugin
$openstack-config --set /etc/neutron/neutron.conf DEFAULT service_plugins neutron.services.l3_router
Now populate the neutron database.
$su -s /bin/sh -c "neutron-db-manage --config-file /etc/neutron/neutron.conf --config-file /etc/neutron/plugin.ini upgrade head" neutron
Now start your neutron-server.