Whenever you make a change to your firewall, on a Fedora/CentOS type system, you will want to save the changes.
The output can be redirected to a file.
# iptables-save > /root/firewall-rules
The following command line restores all rules from /root/firewall-rules assuming that the file /root/firewall-rules exists.
# iptables-restore < /root/firewall-rules
By default, iptables-restore deletes all existing rules before restoring