Taken From : http://www.revsys.com/writings/quicktips/ssh-tunnel.html
ssh -f user@personal-server.com -L 2000:personal-server.com:25 -N
(working example ssh -f root@192.168.40.91 -L 0.0.0.0:8585:192.168.40.91:8585 -N)
The -f tells ssh to go into the background just before it executes the command. This is followed by the username and server you are logging into. The -L 2000:personal-server.com:25 is in the form of -L local-port:host:remote-port. Finally the -N instructs OpenSSH to not execute a command on the remote system.
To kill tunnel use:
netstat -anp | grep 8585 —–> find process ID
kill -9 process ID