centos 7 配置iptables(转) + iptabes规则理解

一、防火墙配置

1、检测并关闭firewall

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systemctl status firewalld.service #检测是否开启了firewall   systemctl stop firewalld.service #关闭firewall   sytsemctl disable firewalld.service #禁止firewall开机自启

2、检测并安装iptables　

1	yum install iptables-services

将规则写入iptables配置文件

1	vi /etc/sysconfig/iptables

1	iptables文件内容：

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*filter :INPUT ACCEPT [0:0] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [0:0] -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT -A INPUT -p icmp -j ACCEPT -A INPUT -i lo -j ACCEPT -A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT -A INPUT -m state --state NEW -m tcp -p tcp --dport 80  -j ACCEPT -A INPUT -j REJECT --reject-with icmp-host-prohibited -A FORWARD -j REJECT --reject-with icmp-host-prohibited COMMIT

systemctl restart iptables.service　　

systemctl enable iptables.service　

表跟链的架构问题