One of the first things you should do after installing CentOS 7 is to configure a decent firewall. The normal firewall that comes preinstalled on CentOS is called iptables – and even though that is a very thorough solution, it’s usually targeted towards more experienced users, and because of its steeper learning curve, it can feel unintuitive to get started with. This is why we recommend a 3rd party solution called ConfigServer Security & Firewall (CSF). It’s free, open-source, and is one of the best ways to manage your firewall needs on CentOS.
