Thanks alzhao.

  1. do I need to do port forwarding for DDNS(without enabling https or ssh access) to work? If so, which port do I need to forward? do I need to do port forward to my secondary router’s ip? or just doing port forwarding enough?
    2.for https or ssh access, Do I need to port forwarding to my secondary router’s ip? or just doing port forwarding enough? Thanks in advance.