Some websites cannot implement port forwarding.

[perlerer]

I tested it and found that generally the established piping server can implement port forwarding. But there are exceptions, such as https://piping.maldun.com/. This website can provide basic piping services, but port forwarding cannot be achieved through netcat or socat. What is the reason? Is there any way to implement port forwarding on this kind of website?

[nwtgck]

@perlerer

Could you check the server supports data streaming? You can use curl like the following video:

piping-server-text-streaming-curl.mov

# sender
curl -T- https://ppng.io/mytext

# receiver
curl https://ppng.io/mytext

If you don't have live text stream, the port forwarding does not work with the server. I guess it is behide a reverse proxy such as Nginx, Cloudflare or something. These proxies may not support streaming response.