When performing a pure DHCP deployment, any of the networking configuration changes applied via agent TUI are not persisted on the node. This means that after the first reboot those changes are not present anymore.

    4.20

    Always

    1. Start a setup without providing any static network configuration
    2. During the boot of each node, enter via the agent TUI in the networking configuration section.
    3. Add/modify some networking configuration (for example, change the DNS server or add a static IP)
    4. Save the results and continue with the installation

    After the first reboot during the installation, changes applied at 3) are not preserved

    Any change applied at 3) must be present as well at the end of the installation.

    From the previous analysis the issue is here https://github.com/openshift/assisted-service/blob/6b3d1e93f5d03a8a22ac296793052bae06ada39e/internal/host/hostcommands/install_cmd.go#L368. AS append the "--copy-network" command flag to coreos-installer only when the static network configuration is detected in InfraEnv, by checking if the infraEnv.StaticNetworkConfig field is empty or if cluster.StaticNetworkConfigured was set (but the latest seems to be deprecated). In general this is not a valid approach for ABI (even though the for the automatic workfklow it incidentally works due https://github.com/openshift/assisted-service/blob/6b3d1e93f5d03a8a22ac296793052bae06ada39e/cmd/agentbasedinstaller/register.go#L184), so an alternative way of forcing it will be required  (as a secondary goal, it will allow also to cleanup the RegisterInfraEnv code from the unnecessary code)