What are the versions of centos firewalls?

CentOS 7 and above use firewalld as a firewall management tool by default, while CentOS 6 and below use iptables. The following is the relevant introduction:

Firewalld firewall for CentOS 7 and above

• Installation : If firewalld is not installed yet, you can use the following command: sudo yum install firewalld.
• Start and set up the power-on self-start : The commands for starting the firewalld service and setting up the power-on self-start are: sudo systemctl start firewalld and sudo systemctl enable firewalld.
• Check the firewall status : Use the command sudo systemctl status firewalld to view the current status of the firewall.
• Add firewall rules : For example, the command that allows SSH services to pass is: sudo firewall-cmd --zone public --add-port 22/tcp --permanent.
• Reload the firewall rules : After adding the rules, you need to use the sudo firewall-cmd --reload command to reload the firewall rules to take effect.
• View added rules : Use the sudo firewall-cmd --list-all command to view the current firewall rules.

CentOS 6 and below iptables firewall

• Installation : If you need to use iptables, you usually don't need to install extra because iptables is part of the Linux kernel.
• Configuration : Configuring iptables rules usually involves editing /etc/sysconfig/iptables files, and then restarting the firewall service using the service iptables restart command to make the rules take effect.

The above information provides an overview of the firewall version used in CentOS systems and its basic operating methods.

The above is the detailed content of What are the versions of centos firewalls?. For more information, please follow other related articles on the PHP Chinese website!