I have tried to recreate this and was unable to, (Contents below replicated in pastebin: https://paste.ubuntu.com/p/Xh6HGGMqBm/ )


(clients) jenkins@mosci-amd64-jslave-persist-840:~/charm-test-infra$ openstack segment create segment1 auto COMPUTE
+-----------------+--------------------------------------+
| Field           | Value                                |
+-----------------+--------------------------------------+
| created_at      | 2020-06-26T08:50:43.000000           |
| updated_at      | None                                 |
| uuid            | b99b7779-03b9-4e64-8eb4-d108c1ac1e32 |
| name            | segment1                             |
| description     | None                                 |
| id              | 1                                    |
| service_type    | COMPUTE                              |
| recovery_method | auto                                 |
+-----------------+--------------------------------------+
(clients) jenkins@mosci-amd64-jslave-persist-840:~/charm-test-infra$ openstack hypervisor list
+----+---------------------+-----------------+---------------+-------+
| ID | Hypervisor Hostname | Hypervisor Type | Host IP       | State |
+----+---------------------+-----------------+---------------+-------+
|  1 | node-flyer.maas     | QEMU            | 10.245.168.33 | up    |
|  2 | node-jaeger.maas    | QEMU            | 10.245.168.31 | up    |
|  3 | node-ritz.maas      | QEMU            | 10.245.168.32 | up    |
+----+---------------------+-----------------+---------------+-------+
(clients) jenkins@mosci-amd64-jslave-persist-840:~/charm-test-infra$ openstack segment host create node-flyer.maas COMPUTE SSH b99b7779-03b9-4e64-8eb4-d108c1ac1e32
+---------------------+--------------------------------------+
| Field               | Value                                |
+---------------------+--------------------------------------+
| created_at          | 2020-06-26T08:58:25.000000           |
| updated_at          | None                                 |
| uuid                | 14a6bab9-0901-4782-8cf2-72dbd4ca13af |
| name                | node-flyer.maas                      |
| type                | COMPUTE                              |
| control_attributes  | SSH                                  |
| reserved            | False                                |
| on_maintenance      | False                                |
| failover_segment_id | b99b7779-03b9-4e64-8eb4-d108c1ac1e32 |
+---------------------+--------------------------------------+
(clients) jenkins@mosci-amd64-jslave-persist-840:~/charm-test-infra$ openstack segment host create node-jaeger.maas COMPUTE SSH b99b7779-03b9-4e64-8eb4-d108c1ac1e32
+---------------------+--------------------------------------+
| Field               | Value                                |
+---------------------+--------------------------------------+
| created_at          | 2020-06-26T08:59:13.000000           |
| updated_at          | None                                 |
| uuid                | f80c6473-889c-4271-8c90-e3ca82d0e4e2 |
| name                | node-jaeger.maas                     |
| type                | COMPUTE                              |
| control_attributes  | SSH                                  |
| reserved            | False                                |
| on_maintenance      | False                                |
| failover_segment_id | b99b7779-03b9-4e64-8eb4-d108c1ac1e32 |
+---------------------+--------------------------------------+
(clients) jenkins@mosci-amd64-jslave-persist-840:~/charm-test-infra$ openstack segment host create node-ritz.maas COMPUTE SSH b99b7779-03b9-4e64-8eb4-d108c1ac1e32
+---------------------+--------------------------------------+
| Field               | Value                                |
+---------------------+--------------------------------------+
| created_at          | 2020-06-26T08:59:29.000000           |
| updated_at          | None                                 |
| uuid                | 424abc91-2659-46b1-b10a-2a5f2baeb4e8 |
| name                | node-ritz.maas                       |
| type                | COMPUTE                              |
| control_attributes  | SSH                                  |
| reserved            | False                                |
| on_maintenance      | False                                |
| failover_segment_id | b99b7779-03b9-4e64-8eb4-d108c1ac1e32 |
+---------------------+--------------------------------------+
(clients) jenkins@mosci-amd64-jslave-persist-840:~/charm-test-infra$ juju run --application nova-compute "uptime"
- Stdout: |2
     08:59:39 up 18:56,  0 users,  load average: 0.55, 0.57, 0.55
  UnitId: nova-compute/2
- Stdout: |2
     08:59:40 up 18:56,  0 users,  load average: 0.57, 0.71, 0.73
  UnitId: nova-compute/1
- Stdout: |2
     08:59:40 up 18:56,  0 users,  load average: 0.39, 0.64, 0.73
  UnitId: nova-compute/0