Create tunnel via the ssh command in linux.
For linux use the following command.
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.