Comment 1 for bug 2071619

Reviewed: https://review.opendev.org/c/starlingx/stx-puppet/+/923161
Committed: https://opendev.org/starlingx/stx-puppet/commit/bbc20004486f54b74d4d1e90f54f65fca3421fa8
Submitter: "Zuul (22348)"
Branch: master

commit bbc20004486f54b74d4d1e90f54f65fca3421fa8
Author: Andre Kantek <email address hidden>
Date: Mon Jul 1 09:23:58 2024 -0300

    Exit network config apply if puppet provides empty configuration

    It was observed that if sysinv-conductor generates, for some reason,
    hieradata for controller-1 (or other nodes) between the host-add
    operation but before the new node's sysinv-agent send the first
    inventory report an empty network config will be generated.

    The script apply_network_config.sh isn't prepared for this case and
    was removing existing configuration without adding another one,
    isolating the node.

    This change adds protection for this case, if an empty configuration
    is detected (only contains the loopback) it will exit with success,
    preserving the current configuration.

    To simulate the problem, after controller-1 was added (with
    system host-update 2 personality=controller) an empty controller-1
    hieradata was generated with "/usr/bin/sysinv-puppet
     create-host-config" in /opt/platform/puppet/24.09/hieradata/. This
    file contained a "network_config" with just the loopback interface.

    Test Plan:

    [PASS] with the empty network_config hieradata observe that the
            network config left by kickstart is preserved, no network
            interruption is detected
    [PASS] after sysinv-agent inventory report proceed with
            controller-1 configuration and unlock the system, the unlock
            operation finishes with success.

    Closes-Bug: 2071619

    Change-Id: Ibb732d1f57e036740a7140c6014328f8a6de0fe5
    Signed-off-by: Andre Kantek <email address hidden>