lazlo:~# nc -l -v -p 44444 &
[1] 29542
lazlo:~# listening on [any] 44444 ...

lazlo:~# iptables -t nat -I PREROUTING -p tcp --dport 999 -j REDIRECT --to-port 44444
lazlo:~# telnet localhost 999
Trying 127.0.0.1...
telnet: Unable to connect to remote host: Connection refused
lazlo:~# telnet localhost 44444
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
connect to [127.0.0.1] from localhost [127.0.0.1] 44639




ÿôÿý

^]
telnet> quit
Connection closed.
[1]+  Done                    nc -l -v -p 44444
lazlo:~#
lazlo:~#
lazlo:~# iptables -t nat -I PREROUTING -p tcp -d 127.0.0.1 --dport 999 -j REDIRECT --to-port 44444
lazlo:~# !nc
nc -l -v -p 44444 &
[1] 29579
lazlo:~# listening on [any] 44444 ...

lazlo:~#
lazlo:~# telnet localhost 44444
Trying 127.0.0.1...
connect to [127.0.0.1] from localhost [127.0.0.1] 44642
Connected to localhost.
Escape character is '^]'.


ÿôÿýÿôÿýÿôÿý^]
telnet> quit
Connection closed.

[1]+  Stopped                 nc -l -v -p 44444