Hi GrievingKoala83 ! It looks like lightning uses the NODE_RANK env var to get the rank of a node, instead of NODE (which is used by pytorch).
We don't set NODE_RANK yet, but you could set it yourself after launchi_multi_node :

import os    
current_conf = task.launch_multi_node(2)
os.environ["NODE_RANK"] = str(current_conf.get("node_rank", ""))

Hope this helps