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CentOS Stream 8 Firewall Setting Tutorial

Apr 14, 2025 pm 03:51 PM
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CentOS Stream 8 Firewall Management Guide: Use firewalld to finely control network access

The CentOS Stream 8 system uses firewalld as a dynamic firewall management tool, which defines the security level of different network traffic based on the concept of "zones". This guide will gradually explain the basic configuration and management methods of firewalld.

1. Install firewalld

If firewalld is not installed, execute the following command:

 sudo dnf install firewalld
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2. Startup and status check

Start the firewalld service:

 sudo systemctl start firewalld
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Check service status:

 sudo systemctl status firewalld
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3. Regional settings and management

Set the default region (for example, set the eth0 interface to the public region):

 sudo firewall-cmd --set-default-zone=public
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View all available areas:

 sudo firewall-cmd --get-zones
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View the currently active area:

 sudo firewall-cmd --get-active-zones
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4. Port rule configuration

Permanently add ports (for example, HTTP port 80):

 sudo firewall-cmd --permanent --add-port=80/tcp
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Apply changes:

 sudo firewall-cmd --reload
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Delete the port (for example, HTTP port 80):

 sudo firewall-cmd --permanent --remove-port=80/tcp
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Apply changes:

 sudo firewall-cmd --reload
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5. IP address access control

Use the rich-rule command to allow access to a specific IP address (for example, to allow access to port 3306 by 192.168.1.100):

 sudo firewall-cmd --permanent --add-rich-rule='rule family="ipv4" source address="192.168.1.100" port port="3306" protocol="tcp" accept'
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Apply changes:

 sudo firewall-cmd --reload
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6. Check the firewall rules

View all firewall rules:

 sudo firewall-cmd --list-all
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7. Firewall switch and power-on start

Turn off the firewall:

 sudo systemctl stop firewalld
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Enable the firewall to start automatically:

 sudo systemctl enable firewalld
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This guide provides basic configuration methods for CentOS Stream 8 firewall. Depending on actual needs, you can flexibly use these commands to set more refined firewall rules. Please note that after modifying the firewall rules, be sure to use the sudo firewall-cmd --reload command to make the changes take effect.

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