Firewall Management
Getting to Know Firewalld

© Gino Santa Maria, Fotolia
Managing a firewall can be a hassle, but it’s worse to manage a breach because you didn’t have one.
Special Thanks: This article was made possible by support from Linux Professional Institute
A firewall is an important part of a security strategy, but it is only one component and is not a security panacea for reasons that will become clear later in the discussion. A host-based firewall protects the local system just as a network firewall protects an entire network or part of a network, such as a DMZ.
Firewalld is the default firewall installed on CentOS 7 and newer, Red Hat Enterprise Linux 7 and newer (RHEL), and Fedora 18 and newer. If you use a Red Hat-based distribution, then you probably have it already. If you use other distributions, it’s available via git and as a tarball from firewalld.org. Firewalld uses zones to define trust levels of network connections or interfaces. Zones are an advanced topic not covered in this article. There will be a future article that covers firewalld zones.
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