Reverting to the iptables Service
If you are not ready to make the break to firewalld, you can still use the iptables service by issuing the following commands.
# systemctl stop firewalld
# systemctl disable firewalld# iptables-service
# touch /etc/sysconfig/iptables
# systemctl start iptables # systemctl enable iptables# touch /etc/sysconfig/ip6tables
# systemctl start ip6tables # systemctl enable ip6table