In this post we’d talk about ‘firewalld’ and it is benefits and how to get it configured in RHEL7 and above systems.
A Note on netfilter
In Linux ‘netfilter’ is being used which is a powerful network filtering sub-system. This allows kernel modules to inspect each packet traversing the system, and it could be dropped or rejected or allowed in a programmatic way and this applies to all incoming, outgoing and forwarded packets. So, in earlier RHEL6.x version we had ‘iptables’ which is a well-known netfilter program. However, in RHEL7.x version and above we've ‘firewalld’ in-place of ‘iptables’.