CentOS Stream 8 Firewall Setting Tutorial
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
2. Startup and status check
Start the firewalld service:
sudo systemctl start firewalld
Check service status:
sudo systemctl status firewalld
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
View all available areas:
sudo firewall-cmd --get-zones
View the currently active area:
sudo firewall-cmd --get-active-zones
4. Port rule configuration
Permanently add ports (for example, HTTP port 80):
sudo firewall-cmd --permanent --add-port=80/tcp
Apply changes:
sudo firewall-cmd --reload
Delete the port (for example, HTTP port 80):
sudo firewall-cmd --permanent --remove-port=80/tcp
Apply changes:
sudo firewall-cmd --reload
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'
Apply changes:
sudo firewall-cmd --reload
6. Check the firewall rules
View all firewall rules:
sudo firewall-cmd --list-all
7. Firewall switch and power-on start
Turn off the firewall:
sudo systemctl stop firewalld
Enable the firewall to start automatically:
sudo systemctl enable firewalld
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.
The above is the detailed content of CentOS Stream 8 Firewall Setting Tutorial. For more information, please follow other related articles on the PHP Chinese website!

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