'Get the backend names for all configured replication targets.'

def get_replication_backend_names(self, config):

    backend_names = []
    replication_devices = config.safe_get('replication_device')
    if replication_devices:
        for replication_device in replication_devices:
            backend_id = replication_device.get('backend_id')
            if backend_id:
                backend_names.append(backend_id)
    return backend_names
