
What is iptables?
It is is a user space application program that allows a system administrator to configure the tables provided by the Linux kernel firewall (implemented as different Netfilter modules) and the chains and rules it stores.
In order to keep down the number of attempted break-ins and to filter the ports opened on your virtual server, it is necessary to properly configure your firewall.
Exim is a popular, powerful and easily configurable mail transfer agent (MTA) included on most Linux operating systems.


The following article will walk you through the steps on how to install LEMP (Linux, Nginx, MariaDB & PHP-FPM) on one of our CentOS 7 
