CentOS 7 防火墙和端口配置

centos 7 防火墙和端口配置
--解决 RHEL 7/ CentOS 7/Fedora 出现Unit iptables.service failed to load

# 第一步,关闭firewall：
CentOS 7.0默认使用的是firewall作为防火墙，这里改为iptables防火墙。

systemctl stop firewalld.service 　　　　#停止firewall
systemctl disable firewalld.service 　　#禁止firewall开机启动

# 第二步,安装iptables-services：

yum install iptables-services

# 第三步,启用iptables-services：

root@vm-xiluhua ~# systemctl enable iptables　　 #启用
Created symlink from /etc/systemd/system/basic.target.wants/iptables.service to /usr/lib/systemd/system/iptables.service.
root@vm-xiluhua ~# service iptables status　　　　#查看状态
Redirecting to /bin/systemctl status  iptables.service
● iptables.service - IPv4 firewall with iptables
   Loaded: loaded (/usr/lib/systemd/system/iptables.service; enabled; vendor preset: disabled)
   Active: inactive (dead)
root@vm-xiluhua ~# service iptables start　　　　 #启动
Redirecting to /bin/systemctl start  iptables.service
root@vm-xiluhua ~# service iptables status
Redirecting to /bin/systemctl status  iptables.service
● iptables.service - IPv4 firewall with iptables
   Loaded: loaded (/usr/lib/systemd/system/iptables.service; enabled; vendor preset: disabled)
   Active: active (exited) since 一 -- :: CST; 8s ago
  Process:  ExecStart=/usr/libexec/iptables/iptables.init start (code=exited, status=/SUCCESS)
 Main PID:  (code=exited, status=/SUCCESS)

10月  :: vm-xiluhua systemd[]: Starting IPv4 firewall with iptables...
10月  :: vm-xiluhua iptables.init[]: iptables: Applying firewall rules: [  确定  ]
10月  :: vm-xiluhua systemd[]: Started IPv4 firewall with iptables.

# 第4步,执行iptables命令开启或关闭端口

# 开启
iptables -A INPUT -p tcp --dport 3690 -j ACCEPT;
# 关闭
iptables -A INPUT -p tcp --dport 3690 -j DROP
# 查看是否有端口3690的配置,并显示行号
iptables -L -n --line-number | grep 3690
# 按行号删除,开启或关闭
iptables -D INPUT 1

#保存规则到iptables,重启配置依然有效
root@vm-xiluhua ~# service iptables save
iptables: Saving firewall rules to /etc/sysconfig/iptables:[  确定  ]