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How to Restrict Network Access Using FirewallD

As a Linux user, you can opt either to allow or restrict network access to some services or IP addresses using the firewalld firewall which is native to CentOS/RHEL 8 and most RHEL based distributions such as Fedora. Learn how to do this in a helpful tutorial.
The firewalld firewall uses the firewall-cmd command-line utility to configure firewall rules.