I've routed all requests from port 80 to port 8080 for my Tomcat server using iptables.
iptables -A PREROUTING -t nat -i eth0 -p tcp --dport 80 -j REDIRECT --to-port 8080
Now http://mydomain.com/
works fine, but people can still access http://mydomain.com:8080
. I see that on other sites this is not possible. Is there anyway to disable direct access to port 8080 via the url?