Comment 5 for bug 1866126

I encountered this bug when deploying octavia as well; the traceback added in the previous comment captured the error quite clearly. It seems that if subnets exist but a router does not (at least in my case), the attempts code creates a router and attempts to iterate over the list of subnets which was not referenced.

Log excerpt:

2021-07-28 01:56:20 INFO juju-log Created router a2f71244-eee6-4697-b302-807346e56cbe
2021-07-28 01:56:20 ERROR juju-log action "configure-resources" failed: "'NoneType' object is not iterable" "Traceback (most recent call last):
  File "/var/lib/juju/agents/unit-octavia-0/charm/actions/configure-resources", line 126, in main
    action(args)
  File "/var/lib/juju/agents/unit-octavia-0/charm/actions/configure-resources", line 62, in configure_resources
    (network, secgrp) = api_crud.get_mgmt_network(
  File "/var/lib/juju/agents/unit-octavia-0/charm/lib/charm/openstack/api_crud.py", line 628, in get_mgmt_network
    for subnet in subnets:
TypeError: 'NoneType' object is not iterable
"