How to fix remote port forwarding failed for listen port 80

Question

I use Serveo and want to expose my localhost site to internet with my own domain.

If I use serveo sudbomain it works perfect. But when I try to use it with my own domain name on port 80,it gets me this error:

Warning: remote port forwarding failed for listen port 80

I use this command:

ssh -R example.com:80:localhost:8080 serveo.net

but if I use different port for my domain It works perfect with that port, like

ssh -R example.com:2468:localhost:8080 serveo.net

when open http://example.com:2468 my site work on that port, but for port 80 won't.

If I use diferent port for my domain it works fine, but how to use it with the default port 80 so example.com to point to my localhost site?

Answer 1

I assume you are running this as a regular user.
Regular users are not allowed to let processes listen on port 80.

To be more complete:
Regular users are only allowed to let something listen on non-privileged ports.
If I remember correctly, the privileged ports are all below 1024.

Become root and try again.