Installing Firewalld on CentOS 8

Firewalld is a dynamic firewall management tool that comes pre-installed on CentOS 8. It provides a convenient way to manage and configure firewall rules and settings on a Linux system. Firewalld offers a more user-friendly interface compared to the traditional iptables command.

Step 1: Updating the System

Before installing Firewalld, it is recommended to update the system's package repositories and installed packages. Open a terminal and run the following commands:

Step 2: Installing Firewalld

To install Firewalld, run the following command in the terminal:

Step 3: Starting and Enabling Firewalld

After the installation completes, start and enable the Firewalld service by executing the following commands:

Step 4: Basic Firewalld Commands

Once Firewalld is installed and running, you can use various commands to manage firewall rules:

• sudo firewall-cmd --state: Check if Firewalld is running.
• sudo firewall-cmd --list-all: Display all active firewall rules.
• sudo firewall-cmd --get-active-zones: Show active firewall zones.
• sudo firewall-cmd --zone=public --add-service=http --permanent: Allow HTTP traffic in the public zone.
• sudo firewall-cmd --reload: Apply changes made to the firewall rules.

Step 5: Configuring Additional Firewall Rules

You can configure specific firewall rules by using the firewall-cmd command. For example, to allow SSH connections, run the following:

Remember to reload the Firewall after making any changes for them to take effect:

By following these steps, you have successfully installed and started Firewalld on CentOS 8. You can now use Firewalld to manage and control the firewall settings according to your needs.