Recently Chinese enforce blocking access to abroad internet resource.
I try to investigate how they do it. They are do not crudely block port or IP.
It looks like that there are some, easy recognizable patterns, at TLS handshake moment, so they just kill this packs, to prevent complete handshake, and make connection.
If I switch port, everything start working properly....till some time.
I think this is OpenVPN protocol design problem. No?