Comment 3 for bug 1930401

So I checked logs of one failure:

 - port 45ed2855-2935-406e-87a8-83ac7cc08a3b failed to reach ACTIVE status, failed at 08.20.28
 - L2 agent provisioned port in time:
   - 2021-05-27 08:19:36.646 138296 DEBUG neutron.db.provisioning_blocks [req-c2b1dbf8-4d37-4ae0-8006-e0cc28097338 - - - - -] Provisioning for port 45ed2855-2935-406e-87a8-83ac7cc08a3b completed by entity L2. provisioning_complete
 - provisioning was not completed by DHCP agent, looking at DHCP agent logs I see they stop at 08:19:28.266:
   - https://b87ba208d44b7f1356ad-f27c11edabee52a7804784593cf2712d.ssl.cf5.rackcdn.com/791365/5/check/neutron-fullstack-with-uwsgi/634ccb1/controller/logs/dsvm-fullstack-logs/TestLegacyL3Agent.test_external_subnet_changed/neutron-dhcp-agent--2021-05-27--08-19-12-515519_log.txt

So seems the issue is that dhcp agent was hanging or stopped