如何在 Linux系统中iptables(防火墙)打开指定的端口(CentOS6.x) |
例:当修改了ssh远程连接端口,如何在iptables上放行新的端口(这里将默认22端口号修改为33端口号)。 输入命令放行33端口。[root@aqxyun ~]# iptables -I INPUT -p tcp --dport 33 -j ACCEPT 查看防火墙规则,发现33端口号已经放行了。[root@aqxyun ~]# iptables -nvL Chain INPUT (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination 0 0 ACCEPT tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:33 295 23186 ACCEPT all -- * * 0.0.0.0/0 0.0.0.0/0 state RELATED,ESTABLISHED 34 2310 ACCEPT icmp -- * * 0.0.0.0/0 0.0.0.0/0 0 0 ACCEPT all -- lo * 0.0.0.0/0 0.0.0.0/0 2342 200K REJECT all -- * * 0.0.0.0/0 0.0.0.0/0 reject-with icmp-host-prohibited Chain FORWARD (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination 0 0 REJECT all -- * * 0.0.0.0/0 0.0.0.0/0 reject-with icmp-host-prohibited Chain OUTPUT (policy ACCEPT 15 packets, 1412 bytes) pkts bytes target prot opt in out source destination iptables规则已经更改,我们需要对规则进行保存。[root@aqxyun ~]# service iptables save iptables: Saving firewall rules to /etc/sysconfig/iptables:[ OK ] 保存完毕,重启iptables服务。[root@aqxyun ~]# service iptables restart iptables: Setting chains to policy ACCEPT: filter [ OK ] iptables: Flushing firewall rules: [ OK ] iptables: Unloading modules: [ OK ] iptables: Applying firewall rules: [ OK ] 同样,用此方法也可以放行web的默认端口80。iptables -I INPUT -p tcp --dport 80 -j ACCEPT && service iptables save && service iptables restart |