Questions on underlying port restrictions in nccl/gloo communication

[kwen2501 (Ke Wen)]

@Fei_Liu

misc/socket.cc:191 NCCL WARN Net : No interface found in the same subnet as remote address ip0:<npt>

This issue may be that host 1 is not in the same subnet as the IP address specified in NCCL_COMM_ID. It is not about the port specified in NCCL_COMM_ID.

For example, if host 0 is in subnet 192.168.1.xx, and host 1 is in subnet 10.0.1.xx, this won’t work.