CentOS 7.0 uses firewall as the firewall by default. Here, it is changed to the iptables firewall step.
1. Close firewall:
systemctl stop firewalld.service #Stop firewall
systemctl disable firewalld.service #Disable firewall startup
firewall-cmd --state #View the default firewall status (notrunning is displayed when it is turned off, and running is displayed when it is turned on)
2. Install iptables firewall:
yum install iptables-services #Installation
vi/etc/sysconfig/iptables #Edit Firewall Profile