tunnel local

[pl@client ~]$ ssh -fNL :2323:target.euphoria.fr:23 pl@server

[pl@client ~]$ netstat -pltn --ip 
Proto Recv-Q Send-Q Local Address               State    PID/Program name   
tcp        0      0 0.0.0.0:2323             LISTEN      1982/ssh            

[pl@client ~]$ ps -C ssh -ocmd
CMD
ssh -fNL :2323:target.euphoria.fr:23 pl@server


[pl@client  ~]$ telnet localhost 2323

[pl@epsilon ~]$ telnet client  2323

tunnel distant

[pl@client ~]$ ssh -R *:2323:target.euphoria.fr:23 pl@server

[pl@server ~]$ netstat -ltn  --ip
Connexions Internet actives (seulement serveurs)
Proto Recv-Q Send-Q Adresse locale          Etat       
tcp        0      0 0.0.0.0:111             LISTEN     
tcp        0      0 127.0.0.1:2323          LISTEN 

[pl@server    ~]$ ssh -fNL *:6666:localhost:2323 localhost

[pl@server    ~]$ netstat -ltn  --ip
Connexions Internet actives (seulement serveurs)
Proto Recv-Q Send-Q Adresse locale          Etat       
tcp        0      0 0.0.0.0:41761           LISTEN     
tcp        0      0 0.0.0.0:6666            LISTEN     
tcp        0      0 0.0.0.0:111             LISTEN     
tcp        0      0 127.0.0.1:2323          LISTEN  

[pl@epsilon ~]$ telnet server 6666
Trying server...
telnet: connect to address server: No route to host

[pl@server ~]$ sudo iptables  -L
Chain INPUT (policy ACCEPT)
target     prot opt source               destination         
ACCEPT     all  --  anywhere             anywhere             state RELATED,ESTABLISHED
ACCEPT     icmp --  anywhere             anywhere            
ACCEPT     all  --  anywhere             anywhere            
ACCEPT     tcp  --  anywhere             anywhere             state NEW tcp dpt:ssh
ACCEPT     tcp  --  anywhere             anywhere             state NEW tcp dpt:smtp
REJECT     all  --  anywhere             anywhere             reject-with icmp-host-prohibited

[pl@server    ~]$ sudo iptables -I INPUT 6 -p tcp --dport 6666 -j ACCEPT
[pl@epsilon   ~]$ telnet server 6666

 Philippe Langevin, April 2013.