1.3. Firewall rules
You can use the firewall rules to implement specific configurations for allowing or blocking network traffic. As a result, you can control the flow of network traffic to protect your system from security threats.
Firewall rules typically define certain criteria based on various attributes. The attributes can be as:
- Source IP addresses
- Destination IP addresses
- Transfer Protocols (TCP, UDP, …)
- Ports
- Network interfaces
The firewalld utility organizes the firewall rules into zones (such as public, internal, and others) and policies. Each zone has its own set of rules that determine the level of traffic freedom for network interfaces associated with a particular zone.