给centos7 安装iptables防火墙

我们都知道centos7默认是没有安装iptables的，那么我们如何在centos7里面安装iptables呢？ 下面就来讲解一下：

1、#停止firewall  systemctl stop firewalld.service 

systemctl disable firewalld.service #禁止firewall开机启动 

firewall-cmd --state #查看默认防火墙状态（关闭后显示notrunning，开启后显示running）

 2、安装iptables防火墙

yum install -y iptables

yum install iptables-services

3、编辑iptables规则

vi /etc/sysyconfig/iptables

# Firewall configuration written by system-config-firewall
# Manual customization of this file is not recommended.
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
-A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
-A INPUT -p icmp -j ACCEPT
-A INPUT -i lo -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 22 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 80 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 443 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 21 -j ACCEPT
-A INPUT -j REJECT --reject-with icmp-host-prohibited
-A FORWARD -j REJECT --reject-with icmp-host-prohibited
COMMIT

4、启动iptables

systemctl start  iptables.service