Octavia controller ovn ports appear as down

[DUFOUR Olivier]

# Context
When performing a new deployment of Octavia with OVN, it is required to perform the action "configure-resources" on Octavia leader's unit.
This action creates a dedicated network for communication between amphoraes and Octavia controllers. After the action, all Octavia units end up with a hm-0 interface from OVN and Openstack is made aware of such ports.

# Problem :
This triggers an alarm on the monitoring because of Octavia OVN's ports being detected as "DOWN" although they are functional. (It is possible to ping each controllers and OVN metadata's port)

# Environment :
* MAAS 3.4.1
* Juju 3.4
* Ubuntu Jammy
* Openstack :
  * Yoga (channel: yoga/stable)
  * Antelope/2023.1 (channel 2023.1/stable)
  * Bobcat/2023.2 (channel 2023.2/stable)

# Reproducer :
* Deploy a basic bundle of Octavia + OVN (See attached one for Jammy Yoga)
* Unseal Vault and generate a root CA with Vault
* configure Octavia with certificates and run "configure-resources"
--- When Octavia is in active/idle state
All hm-0 networks are up, all units can ping each other and the ovn-metadata IP
* use the command "openstack port list"
Currently :
 * notice all octavia controllers port to be "DOWN"
Expected :
 * all Octavia controllers port should appear as "ACTIVE"

# Workaround :
restart neutron-api service on all neutron-api units :

$ juju exec -a neutron-api 'systemctl restart neutron-server.service'

# Before workaround
$ openstack port list --long --max-width 100
+-----------+-----------+-------------+--------------------+--------+-----------------+--------------+-----------------+
| ID | Name | MAC Address | Fixed IP Addresses | Status | Security Groups | Device Owner | Tags |
+-----------+-----------+-------------+--------------------+--------+-----------------+--------------+-----------------+
| 2157854d- | octavia- | fa:16:3e:b8 | ip_address='fc00:1 | DOWN | None | neutron:LOAD | charm-octavia, |
| b1eb-42c9 | health- | :f5:81 | e72:dae0:4dba:f816 | | | BALANCERV2 | charm-octavia- |
| -8d76-30f | manager-o | | :3eff:feb8:f581', | | | | octavia-1 |
| 37288ed8c | ctavia-1- | | subnet_id='9a9d642 | | | | |
| | listen- | | 5-70f0-4a57-9cd1-f | | | | |
| | port | | 84e812970b8' | | | | |
| 3e712b5a- | octavia- | fa:16:3e:74 | ip_address='fc00:1 | DOWN | None | neutron:LOAD | charm-octavia, |
| 0bf4-4382 | health- | :e9:43 | e72:dae0:4dba:f816 | | | BALANCERV2 | charm-octavia- |
| -8154-efc | manager-o | | :3eff:fe74:e943', | | | | octavia-0 |
| 47268d406 | ctavia-0- | | subnet_id='9a9d642 | | | | |
| | listen- | | 5-70f0-4a57-9cd1-f | | | | |
| | port | | 84e812970b8' | | | | |
| e8057739- | octavia- | fa:16:3e:70 | ip_address='fc00:1 | DOWN | None | neutron:LOAD | charm-octavia, |
| 0338-40a8 | health- | :ae:a6 | e72:dae0:4dba:f816 | | | BALANCERV2 | charm-octavia- |
| -bd92-bed | manager-o | | :3eff:fe70:aea6', | | | | octavia-2 |
| 04215569d | ctavia-2- | | subnet_id='9a9d642 | | | | |
| | listen- | | 5-70f0-4a57-9cd1-f | | | | |
| | port | | 84e812970b8' | | | | |
| fa5621cc- | | fa:16:3e:ea | ip_address='fc00:1 | ACTIVE | None | network:rout | |
| 1f63-4763 | | :c2:35 | e72:dae0:4dba::', | | | er_interface | |
| -b394-3ce | | | subnet_id='9a9d642 | | | | |
| 53590cf4a | | | 5-70f0-4a57-9cd1-f | | | | |
| | | | 84e812970b8' | | | | |
| fc7a1cf1- | | fa:16:3e:16 | ip_address='fc00:1 | DOWN | None | network:dist | |
| 6161-4cbb | | :55:ea | e72:dae0:4dba:f816 | | | ributed | |
| -8928-54f | | | :3eff:fe16:55ea', | | | | |
| 9ea86c323 | | | subnet_id='9a9d642 | | | | |
| | | | 5-70f0-4a57-9cd1-f | | | | |
| | | | 84e812970b8' | | | | |
+-----------+-----------+-------------+--------------------+--------+-----------------+--------------+-----------------+

# After workaround
$ openstack port list --long --max-width 100
+-----------+-----------+-------------+--------------------+--------+-----------------+--------------+-----------------+
| ID | Name | MAC Address | Fixed IP Addresses | Status | Security Groups | Device Owner | Tags |
+-----------+-----------+-------------+--------------------+--------+-----------------+--------------+-----------------+
| 2157854d- | octavia- | fa:16:3e:b8 | ip_address='fc00:1 | ACTIVE | None | neutron:LOAD | charm-octavia, |
| b1eb-42c9 | health- | :f5:81 | e72:dae0:4dba:f816 | | | BALANCERV2 | charm-octavia- |
| -8d76-30f | manager-o | | :3eff:feb8:f581', | | | | octavia-1 |
| 37288ed8c | ctavia-1- | | subnet_id='9a9d642 | | | | |
| | listen- | | 5-70f0-4a57-9cd1-f | | | | |
| | port | | 84e812970b8' | | | | |
| 3e712b5a- | octavia- | fa:16:3e:74 | ip_address='fc00:1 | ACTIVE | None | neutron:LOAD | charm-octavia, |
| 0bf4-4382 | health- | :e9:43 | e72:dae0:4dba:f816 | | | BALANCERV2 | charm-octavia- |
| -8154-efc | manager-o | | :3eff:fe74:e943', | | | | octavia-0 |
| 47268d406 | ctavia-0- | | subnet_id='9a9d642 | | | | |
| | listen- | | 5-70f0-4a57-9cd1-f | | | | |
| | port | | 84e812970b8' | | | | |
| e8057739- | octavia- | fa:16:3e:70 | ip_address='fc00:1 | ACTIVE | None | neutron:LOAD | charm-octavia, |
| 0338-40a8 | health- | :ae:a6 | e72:dae0:4dba:f816 | | | BALANCERV2 | charm-octavia- |
| -bd92-bed | manager-o | | :3eff:fe70:aea6', | | | | octavia-2 |
| 04215569d | ctavia-2- | | subnet_id='9a9d642 | | | | |
| | listen- | | 5-70f0-4a57-9cd1-f | | | | |
| | port | | 84e812970b8' | | | | |
| fa5621cc- | | fa:16:3e:ea | ip_address='fc00:1 | ACTIVE | None | network:rout | |
| 1f63-4763 | | :c2:35 | e72:dae0:4dba::', | | | er_interface | |
| -b394-3ce | | | subnet_id='9a9d642 | | | | |
| 53590cf4a | | | 5-70f0-4a57-9cd1-f | | | | |
| | | | 84e812970b8' | | | | |
| fc7a1cf1- | | fa:16:3e:16 | ip_address='fc00:1 | DOWN | None | network:dist | |
| 6161-4cbb | | :55:ea | e72:dae0:4dba:f816 | | | ributed | |
| -8928-54f | | | :3eff:fe16:55ea', | | | | |
| 9ea86c323 | | | subnet_id='9a9d642 | | | | |
| | | | 5-70f0-4a57-9cd1-f | | | | |
| | | | 84e812970b8' | | | | |
+-----------+-----------+-------------+--------------------+--------+-----------------+--------------+-----------------+

[DUFOUR Olivier (odufourc)]

Adding readable output of Openstack port list command before and after the workaround