The system application-update -n stx-openstack -v <new-app-version> command is used for corrective content (bug fixes) -type updates to the running containerized openstack application.
This means that the system application-update -n stx-openstack is not used for upgrading between OpenStack releases (e.g. Train to Ussuri). The system application-update assumes that there is no data schema changes or data migration required in order to update to the new openstack container image(s).
The system application-update -n stx-openstack effectively performs a helm upgrade of one or more of the OpenStack Helm chart releases within the FluxCD Application. One or all of the containerized OpenStack deployments will be updated according to their deployment specification.
Compute nodes do not need to be reset, and hosted application VMs are not impacted.