How to Install Iptables on CentOS 7
You may already know that CentOS 7 use Firewalld as the front end interface to manage netfilter firewall and not Iptables.
So the purpose of this tutorial is to learn how to install and configure Iptables on CentOS 7 Linux, since many of the Linux system administrators still prefer Iptables over Firewalld. So do the following steps.
Install Iptables on CentOS 7
First, we need to install Iptables because it is not there by default with the latest CentOS 7 release. But we can easily install Iptables with the yum software manager.
yum install iptables-services
Disable Firewalld Service
We cannot have two front end interface to manage netfilter firewall rules because it does not work that way. So we need to disable CentOS 7 Firewalld Service first. Just execute the following commands in the terminal
systemctl stop firewalld.service
systemctl disable firewalld.service
systemctl mask firewalld.service
Start and Enable Iptables
Last step is to start and enable Iptables for both IPv4 and IPv6. To do that execute the following commands in the terminal
systemctl start iptables.service
systemctl enable iptables.service
systemctl start ip6tables.service
systemctl enable ip6tables.service
Now just like CentOS 6, you can find the main configuration file inside the /etc/sysconfig Directory.