I'm learning about iptables, firewalling, routing and so on. I'm on Linux, Centos7, and I've set up a local port forwarding to localhost with:firewall-cmd --add-forward-port=port=2023:proto=tcp:toport=22It is working as expected, trying from another machine. Locally, is not visible. I've tried with netstat and ss, nmap lsof and nc. Nothing, all of them sees everything except the 2023, even if it is currently forwarding an ssh session.After much reading, here on stackexchange I found a way to make it visible locally, (from iptables: redirect local request with NAT), but actually that is not a solution, it just made me understand why is not visible from local, but I really would like to know if exists a way to check it locally.. Or the only option is the remote connection?Thank you :)Edit:The set up of the test machine is easy, just execute the firewall-cmd line I wrote in this question. No other rules added. Then test it with ssh (ore nmap) from outside: works. Check it from localhost itself: both ssh and nmap gives connection refused.Edit2:Sorry, I wrote the firewall-cmd line incorrectly with a :toaddr=127.0.0.1 at the end, fixed.
How check a port forwarded from localhost to localhost on.. localhost?
networking;iptables;port forwarding;nat;firewalld