This is a much simpler version of Huawei's bms-network-config, which can do a lot more.
This script is simple and does nothing more than writing out ifcfg-* files from the network_data.json configuration.
It is designed to coexist with cloud-init.
It should be started before the network is brought up and before cloud-init-local runs.
It will then look for a config-2 drive metadata source and openstack/latest/network_data.json there.
If this is not found, the script will exit.
Otherwise it creates the network config files, disables the cloud-init-local script and the config drive data source (it is not correct on OTC, unfortunately).
The distro's network setup scripts will then bring up the network successfully, so cloud-init can retrieve the network OpenStack datasource and configure the instance correctly.