commit a5a5c5e060c37c4d0ec5fff125253ca02c1f1817
Author: Sam Morrison <sorrison@gmail.com>
Date:   Thu Oct 1 09:06:53 2020 +1000

    Handle case where no networks are selected at create
    
    Currently trove will error when no networks are selected
    and no management network is configured. This change will
    pass in None as the nics to nova server create which will
    let nova choose the network.
    
    Change-Id: Ica4f888bf1bc7b771cdfcb0af5c104b2aa6410fe
    Story: 2008213
    Task: 40999

diff --git a/trove/taskmanager/models.py b/trove/taskmanager/models.py
index 9e3253f..5c0d28f 100755
--- a/trove/taskmanager/models.py
+++ b/trove/taskmanager/models.py
@@ -511,6 +511,9 @@ class FreshInstanceTasks(FreshInstance, NotifyMixin, ConfigurationMixin):
                      self.id)
             networks.append({"port-id": port_id})
 
+        if not CONF.management_networks and not networks:
+            return None
+
         # Create port in the user defined network, associate floating IP if
         # needed
         if len(networks) > 1 or not CONF.management_networks: