Unable to convert AIO-DX from switch-based to direct-connect

[Victor Romano]

Brief Description
-----------------
Trying to convert a duplex system to duplex-direct after the initial configuration was completed results in an error: "Cannot modify system mode when it is set to duplex".

Severity
--------
Standard

Steps to Reproduce
------------------
Follow the guide as described in Convert a Duplex System to Direct Connection documentation.

Expected Behavior
------------------
Proceed through all of the steps in the documentation without any errors and successfully convert the system to an AIO-DX direct connection.

Actual Behavior
----------------
After executing the system modify command in Step 1, a "Cannot modify system mode when it is set to duplex" error is outputted. Unable to proceed with the rest of the steps.

Reproducibility
---------------
100% reproducible

System Configuration
--------------------
Standalone AIO-DX

Branch/Pull Time/Commit
-----------------------
NA

Last Pass
---------
NA

Timestamp/Logs
--------------
bash.log

2022-12-20T10:58:37.000 controller-0 -sh: info HISTORY: PID=2499011 UID=42425 system modify --system_mode=duplex-direct

output from CLI

The system will be reconfigured to AIO direct connect.
The controllers need to be physically accessed to reconnect network cables. Please check the admin guide for prerequisites before continue.
Are you sure you want to continue [yes/N]: yes
Please follow the admin guide to complete the reconfiguration.
Cannot modify system mode when it is set to duplex.

sysinv.log

sysinv 2022-12-20 10:58:41.345 97812 WARNING wsme.api [-] Client-side error: Cannot modify system mode when it is set to duplex.: ClientSideError: Cannot modify system mode when it is set to duplex.

Test Activity
-------------
[Sanity, Feature Testing, Regression Testing, Developer Testing, Evaluation, Other - Please specify]

Workaround
----------
No workaround available

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/starlingx/config/+/869864
Committed: https://opendev.org/starlingx/config/commit/68b063395519aa4c35f91925ea65b3aebfccf59b
Submitter: "Zuul (22348)"
Branch: master

commit 68b063395519aa4c35f91925ea65b3aebfccf59b
Author: Victor Romano <email address hidden>
Date: Wed Jan 11 14:54:49 2023 -0300

    System mode modify fails for duplex systems

    The system modify command was not working properly to update
    the system_mode on duplex systems, so updating from duplex to
    duplex-direct and vice versa was not possible. Changes were
    made to ensure that this modification could be made
    while keeping the SX to DX update rules implemented.
    Additionally, the same rules applied during simplex to duplex
    migration were also applied during simplex to duplex-direct
    migration.

    Automated tests were also added to make sure future changes
    don't change the behaviour of the system without warnings.

    Test plan:
    PASS - Install and bootstrap SX, migrate it to DX and
    duplex-direct and check if the system modify command is
    working properlly on CentOS.
    PASS - Install and bootstrap SX, migrate it to DX and
    duplex-direct and check if the system modify command is
    working properlly on Debian.

    Closes-bug: 2002561

    Signed-off-by: Victor Romano <email address hidden>
    Change-Id: I42cff0291945a42b10fa9a4abecaf3c936ffc7e6