Problem1, Sechma not match:

Exception: {u'error': u'unknown database', u'details': u'get_schema request specifies unknown database OVN_Southbound', u'syntax': u'["OVN_Southbound"]'}

Solution

Mybe the ovn-sb or ovn-nb can't be conected throuth TCP. So set the connection

ovn-nbctl set-connection ptcp:6641:{ctrl_ip}
ovn-sbctl set-connection ptcp:6642:{ctrl_ip}

NOTE: the OVN-SB and OVN-NB database will be automatically created when you install the packages. But the connection will use the unix socket as default. You need to configure the TCP as needed.