This problem was detected in "ServersNegativeTestJSON" [1]. When a server is created ("cls.create_test_server"), if a network is not defined but several networks are present in this project, Nova raises the exception "NetworkAmbiguous", a seen in this log snippet:
Sep 13 23:44:15.520980 ubuntu-bionic-limestone-regionone-0011283625 <email address hidden>[27339]: DEBUG nova.network.neutronv2.api [None req-c95ecec2-8d10-4984-8ba9-b608161dd645 tempest-ServersNegativeTestJSON-445859222 tempest-ServersNegativeTestJSON-445859222] validate_networks() for None {{(pid=27340) validate_networks /opt/stack/nova/nova/network/neutronv2/api.py:2251}}
Sep 13 23:44:15.754945 ubuntu-bionic-limestone-regionone-0011283625 <email address hidden>[27339]: INFO nova.api.openstack.wsgi [None req-c95ecec2-8d10-4984-8ba9-b608161dd645 tempest-ServersNegativeTestJSON-445859222 tempest-ServersNegativeTestJSON-445859222] HTTP exception thrown: Multiple possible networks found, use a Network ID to be more specific.
We can see that the network information provided to the server creation is empty but Nova tries to assign a default single network for this server. However Nova does not assign this default network because several networks are present for this project ID. In this case, the server creation should be specific passing the network information.
[1]https://58a87e825b9766115d07-cec36eea8e90c9127fc5a72b798cfeab.ssl.cf2.rackcdn.com/670177/9/check/networking-ovn-tempest-dsvm-ovs-release/b58638a/testr_results.html.gz
Fix proposed to branch: master /review. opendev. org/682964
Review: https:/