maas-import-pxe-files can be always run as a celerybeat job which is targeted at all workers. Each worker would be sent an optional squid proxy address in the job parameters. If the proxy is not set, then download from t'internet. The squid proxy address can be a region controller setting.
This means that the import could also be initiated remotely from the UI/API etc.
Further discussion:
maas-import- pxe-files can be always run as a celerybeat job which is targeted at all workers. Each worker would be sent an optional squid proxy address in the job parameters. If the proxy is not set, then download from t'internet. The squid proxy address can be a region controller setting.
This means that the import could also be initiated remotely from the UI/API etc.