Turning off your CentOS Firewall
If you are having issues connecting to your CentOS machine and think that the firewall could be causing the issue then here is how to disable it.
# service iptables save # service iptables stop # chkconfig iptables off
When you've finished your testing you can re-enable the firewall with the following.
# service iptables start # chkconfig iptables on
This helped me a lot when trying to determine whether my machine or router was blocking connection to a certain port.