Enable listening on port 51212 for telnet

I’ve been reading about the Telnet topic on the forum, but I can’t find the solution.

I have a server which is linked to the tunnel. I can access the server’s web platform via HTTPS, but I need connectivity to a port (51212) via Telnet.

I tested by opening the port on the router and accessing through the public IP, and this solution works, but I want to use it via a Zero Trust tunnel.

From what I’ve read, cloudflared blocks Telnet communications among others, and I don’t know how to allow these communications if that’s the case.

I am managing communications directly from the Zero Trust platform. I haven’t touched anything on the local application.

Hello you can do this via this article. Arbitrary TCP · Cloudflare Zero Trust docs It will require that the devices connecting have cloudflareD installed.

Hello! Thank you for the help.
The server needs to connect through port 51212 to some physical terminals. These are dumb terminals and do not allow any other options than to input an IP address and port.

The terminals send information through port 51212 and receive information through port 51211.

It’s a Suprema system with the Safire control center access control.