Failed to upgrade 3.4.1 to 3.4.2

[maasuser1]

```
clouduser@maas:~$ sudo snap refresh maas --channel=3.4/stable
[sudo] password for clouduser:
error: cannot perform the following tasks:
- Run post-refresh hook of "maas" snap if present (run hook "post-refresh":
-----
Operations to perform:
  Apply all migrations: auth, contenttypes, maasserver, metadataserver, piston3, sessions, sites
Running migrations:
  Applying maasserver.0318_add_port_to_forward_dns_servers...Traceback (most recent call last):
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
psycopg2.errors.DuplicateColumn: column "port" of relation "maasserver_forwarddnsserver" already exists

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/snap/maas/35359/bin/maas-region", line 8, in <module>
    sys.exit(run())
  File "/snap/maas/35359/lib/python3.10/site-packages/maasserver/region_script.py", line 81, in run
    run_django(is_snap, is_devenv)
  File "/snap/maas/35359/lib/python3.10/site-packages/maasserver/region_script.py", line 70, in run_django
    management.execute_from_command_line()
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/core/management/__init__.py", line 419, in execute_from_command_line
    utility.execute()
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/core/management/__init__.py", line 413, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/core/management/base.py", line 354, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/core/management/base.py", line 398, in execute
    output = self.handle(*args, **options)
  File "/snap/maas/35359/lib/python3.10/site-packages/maasserver/management/commands/dbupgrade.py", line 125, in handle
    call_command(
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/core/management/__init__.py", line 181, in call_command
    return command.execute(*args, **defaults)
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/core/management/base.py", line 398, in execute
    output = self.handle(*args, **options)
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/core/management/base.py", line 89, in wrapped
    res = handle_func(*args, **kwargs)
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/core/management/commands/migrate.py", line 244, in handle
    post_migrate_state = executor.migrate(
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/db/migrations/executor.py", line 117, in migrate
    state = self._migrate_all_forwards(state, plan, full_plan, fake=fake, fake_initial=fake_initial)
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/db/migrations/executor.py", line 147, in _migrate_all_forwards
    state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial)
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/db/migrations/executor.py", line 227, in apply_migration
    state = migration.apply(state, schema_editor)
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/db/migrations/migration.py", line 126, in apply
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/db/migrations/operations/fields.py", line 104, in database_forwards
    schema_editor.add_field(
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/db/backends/base/schema.py", line 522, in add_field
    self.execute(sql, params)
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/db/backends/base/schema.py", line 145, in execute
    cursor.execute(sql, params)
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/db/backends/utils.py", line 66, in execute
    return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/db/backends/utils.py", line 75, in _execute_with_wrappers
    return executor(sql, params, many, context)
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/db/backends/utils.py", line 79, in _execute
    with self.db.wrap_database_errors:
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/db/utils.py", line 90, in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File "/snap/maas/35359/usr/lib/python3/dist-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
django.db.utils.ProgrammingError: column "port" of relation "maasserver_forwarddnsserver" already exists

Traceback (most recent call last):
  File "/snap/maas/35359/bin/maas", line 8, in <module>
    sys.exit(main())
  File "/snap/maas/35359/lib/python3.10/site-packages/maascli/__init__.py", line 39, in main
    options.execute(options)
  File "/snap/maas/35359/lib/python3.10/site-packages/maascli/snap.py", line 481, in __call__
    raise exc
  File "/snap/maas/35359/lib/python3.10/site-packages/maascli/snap.py", line 478, in __call__
    self.handle(options)
  File "/snap/maas/35359/lib/python3.10/site-packages/maascli/snap.py", line 1037, in handle
    sys.exit(migrate_db())
  File "/snap/maas/35359/lib/python3.10/site-packages/maascli/snap.py", line 386, in migrate_db
    subprocess.check_call(
  File "/usr/lib/python3.10/subprocess.py", line 369, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['/snap/maas/35359/bin/maas-region', 'dbupgrade']' returned non-zero exit status 1.
-----)
```

[maasuser1 (maasuser1)]

Fixed by droped `port` column from `maasserver_forwarddnsserver` table.

https://bugs.launchpad.net/maas/+bug/2058898

[Anton Troyanov (troyanov)]

Hi maasuser1,

Is it possible that you were using 3.4/edge to install MAAS 3.4.1?
That would explain why you already had `port` column.

https://git.launchpad.net/maas/commit/?id=99b3d1f1fb61dbdc25000c3394faa547df5749bb
https://git.launchpad.net/maas/commit/?id=a552d252204f0abaaa84eee4d36024fa2498c61e
https://git.launchpad.net/maas/commit/?id=a5e22161ba48e57b5465e7b491de0e376655b8f2

We didn't notice any migration issues when upgrading our lab from 3.4.1 to 3.4.2 (while being on 3.4/stable)

[maasuser1 (maasuser1)]

Thank you, Anton, yes. I remember I installed 3.4/edge and then refreshed to 3.4.1/stable a few months ago.

[Anton Troyanov (troyanov)]

We're excited for community users to try the latest and greatest version of MAAS, but unfortunately we can't guarantee that edge [0] channel will always work.

I am glad that you were able to solve the issue.

May I ask you to share result of the following query? Just to ensure that manual column removal won't lead to other issues in the future:
```
select * from django_migrations
where app = 'maasserver'
order by applied desc limit 20;
```

[0]: Edge releases often include a moving stream of changes without QA or review promises and are typically built automatically by a CI process from an arbitrary source code snapshot. Often the CI will only publish after some sort of automatic QA passed, and code reviews remain a good practice, but these are project specific. Assume edge releases may break often.

[maasuser1 (maasuser1)]

Thanks for the information!

```csv
361,maasserver,0318_add_port_to_forward_dns_servers,2024-05-09 14:41:42.106137 +00:00
360,maasserver,0305_add_port_to_forward_dns_servers,2024-03-12 23:24:59.398346 +00:00
358,maasserver,0304_interface_params_no_autoconf,2023-12-21 19:30:53.587876 +00:00
357,maasserver,0303_interface_params_cleanups,2023-12-21 19:30:53.564463 +00:00
356,maasserver,0302_big_auto_field,2023-12-21 19:30:53.224573 +00:00
355,maasserver,0301_discovery_ignore_fks,2023-12-21 19:29:38.975402 +00:00
354,maasserver,0300_current_script_set_foreign_keys_readd,2023-12-21 19:29:38.445091 +00:00
353,maasserver,0299_current_script_set_foreign_keys_cleanup,2023-12-21 19:29:38.180414 +00:00
352,maasserver,0298_current_script_set_foreign_keys_drop_indexes,2023-12-21 19:29:37.995746 +00:00
351,maasserver,0297_move_metadata_script_models,2023-12-21 19:29:37.759516 +00:00
350,maasserver,0296_move_metadata_node_models,2023-12-21 19:29:37.300648 +00:00
347,maasserver,0295_macaddress_text_field,2023-12-21 19:29:36.533792 +00:00
346,maasserver,0294_keyring_data_binary_field,2023-12-21 19:29:36.056234 +00:00
345,maasserver,0293_drop_verbose_regex_validator,2023-12-21 19:29:36.032877 +00:00
344,maasserver,0292_use_builtin_json_field,2023-12-21 19:29:35.949926 +00:00
343,maasserver,0291_rdns_hostnames_as_array,2023-12-21 19:29:34.823411 +00:00
334,maasserver,0290_migrate_node_power_parameters,2023-12-21 14:04:55.230509 +00:00
333,maasserver,0289_vault_secret,2023-12-21 14:04:55.119993 +00:00
332,maasserver,0288_rootkey_material_secret,2023-12-21 14:04:55.025346 +00:00
331,maasserver,0287_add_controller_info_vault_flag,2023-12-21 14:04:54.950965 +00:00

```

[Anton Troyanov (troyanov)]

Oh, this doesn't seem to be right and might lead to other issues in the future :(

```
361,maasserver,0318_add_port_to_forward_dns_servers,2024-05-09 14:41:42.106137 +00:00
360,maasserver,0305_add_port_to_forward_dns_servers,2024-03-12 23:24:59.398346 +00:00
```

So I guess one came from [0] and another one from [1]

[0]: https://git.launchpad.net/maas/commit/?id=99b3d1f1fb61dbdc25000c3394faa547df5749bb
[1]: https://git.launchpad.net/maas/commit/?id=a5e22161ba48e57b5465e7b491de0e376655b8f2

Let's do an open surgery on the database? Please create a backup before proceeding!

```sql
# drop duplicate migrations
delete from django_migrations where id in (360, 361);
# drop port column
alter table maasserver_forwarddnsserver drop column port;
```

Once the database is cleaned up, please run `maas migrate` which should apply only one `add_port_to_forward_dns_servers` migration.

You should end up with something like this:
```csv
{new ID},maasserver,0318_add_port_to_forward_dns_servers, {timestamp}
358,maasserver,0304_interface_params_no_autoconf,2023-12-21 19:30:53.587876 +00:00
```

[maasuser1 (maasuser1)]

Thanks Anton.

```
362,maasserver,0318_add_port_to_forward_dns_servers,2024-05-11 09:21:31.230599 +00:00
358,maasserver,0304_interface_params_no_autoconf,2023-12-21 19:30:53.587876 +00:00
357,maasserver,0303_interface_params_cleanups,2023-12-21 19:30:53.564463 +00:00
356,maasserver,0302_big_auto_field,2023-12-21 19:30:53.224573 +00:00
355,maasserver,0301_discovery_ignore_fks,2023-12-21 19:29:38.975402 +00:00
```