This script is for OS X. It check if the ssh forwording process exists, if not, create one. It is created for adding to crontab.

build_ssh_tunnel.sh

#!/bin/bash
listen=`netstat -f inet -p tcp -nRa | grep 'LISTEN' | awk '{ print $4 }' | grep 10024`
if [ $listen ]; then
    if [ $listen = '127.0.0.1.10024' ]; then
        exit
    fi  
fi

nohup ssh -ntt -D 10024 user@yourdomain.com > /dev/null 2>&1 &
exit