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CentOS7下Firewall防火墙配置用法详解

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修改防火墙配置文件之前,需要对之前防火墙做好备份

重启防火墙后,需要确认防火墙状态和防火墙规则是否加载,若重启失败或规则加载失败,则所有请求都会被防火墙拦截

systemctl status firewall   
    #查看firewall服务状态
firewall-cmd --state        
    #查看firewall的状态
firewall-cmd --list-all 
    #查看防火墙规则(只显示/etc/firewalld/zones/public.xml中防火墙策略)
firewall-cmd --list-all-zones 
    #查看所有的防火墙策略(即显示/etc/firewalld/zones/下的所有策略)
firewall-cmd --reload
    #重新加载配置文件

方法1、修改配置文件/etc/firewalld/zones/public.xml,重启或重新加载配置生效

[root@nginx01 zones]# cat public.xml
<?xml version="1.0" encoding="utf-8"?>
<zone>
  <short>Public</short>
  <description>For use in public areas. You do not trust the other computers on networks to not harm your computer. Only selected incoming connections are accepted.</description>
  <rule family="ipv4">
    <source address="122.x.x.234"/>
    <port protocol="udp" port="514"/>
    <accept/>
  </rule>
  <rule family="ipv4">
    <source address="123.x.x.14"/>
    <port protocol="tcp" port="10050-10051"/> ##可以开放端口地址范围"10050-10051",不单只限定一个端口
    <accept/>
  </rule>
 <rule family="ipv4">
    <source address="192.x.x.114"/>      ##放通指定ip,指定端口、协议
    <port protocol="tcp" port="80"/>
    <accept/>
  </rule>
<rule family="ipv4">                        ##放通任意ip访问服务器的9527端口
    <port protocol="tcp" port="9527"/>
    <accept/>
  </rule>
</zone>

firewall-cmd --reload

ervice firewalld restart #使配置文件重新加载

方法2、命令行修改防火墙策略,仍需重启firewalld.service或重新加载防火墙配置文件

firwall-cmd --permanent --add-port=9527/tcp    插入防火墙规则,放通9527端口。
success 
 
#命令执行成功同时,在/etc/firewall/zones/public.xml中自动生成该规则。
<zone>
  <short>xx.</short>
  <description>xxx.</description>
  <port protocol="tcp" port="9527"/>
</zone>
 
service firewalld restart
firewall-cmd --reload         #重启或重新加载配置文件,使配置生效   
firewall-cmd --list-all
firewall-cmd --permanent --query-port=9527/tcp    #查询刚插入的规则是否生效
 

firewall-cmd --zone=public --add-port=80/tcp --permanent    添加防火墙规则;

firewall-cmd --reload    重新加载防火墙;

firewall-cmd --permanent --zone=public --add-masquerade    允许内网上网;

/etc/firewalld/zones/public.xml添加策略标准规则:

firewall-cmd --permanent --add-rich-rule 'rule family=ipv4 source address=122.x.x.234/24 port port=5423 protocol=tcp drop'    
firewall-cmd --permanent --add-rich-rule 'rule family=ipv4 source address=122.x.x.234 port port=80 protocol=tcp accept'    
firewall-cmd --reload
[root@nginx02 ~]# firewall-cmd --list-all
public (default, active)
  interfaces: em1
  sources: 
  services: 
  ports: 
  masquerade: no
  forward-ports: 
  icmp-blocks: 
  rich rules: 
    rule family="ipv4" source address="122.x.x.234" port port="5234" protocol="tcp" drop
    rule family="ipv4" source address="122.x.x.234" port port="80" protocol="tcp" accept
    rule family="ipv4" source address="123.x.x.14" port port="10050-10051" protocol="tcp" accept

二、以服务的形式(例如:ssh.xml/http.xml)添加新的防火墙策略

cat /etc/firewalld/zones/ssh.xml
<?xml version='1.0' encoding='utf-8'?>
<zone>
  <short>ssh</short>
  <description>ssh.</description>
#fortress-new
  <source address='122.x.x.2/29'/>
  <service name='ssh'/>
</zone>
 
firewall-cmd --list-all-zones

ssh
  interfaces: 
  sources: 122.x.x.2/29 
  services: ssh
  ports: 
  masquerade: no
  forward-ports: 
  icmp-blocks: 
  rich rules:
...

因为在/usr/lib/firewalld/services/中事先定义了ssh.xml的相应的规则

cat /usr/lib/firewalld/services/ssh.xml

<?xml version="1.0" encoding="utf-8"?>
<service>
  <short>SSH</short>
  <description>Secure Shell (SSH) is a protocol for logging into and executing commands on remote machines. It provides secure encrypted communications. If you plan on accessing your machine remotely via SSH over a firewalled interface, enable this option. You need the openssh-server package installed for this option to be useful.</description>
  <port protocol="tcp" port="22"/>
</service>
##定义ssh.xml服务使用的协议,和通信的端口信息。

自定义服务(mongo.xml)模块

cat /usr/lib/firewalld/services/mongo.xml
<service>
  <short>mongo</short>
  <description>The service of mongo.</description>
  <port protocol="tcp" port="27017"/>
</service>

防火墙应用服务器模块

cat /etc/firewalld/zones/mongo.xml

<zone>
  <short>mongo</short>
  <description>mongo service</description>
  <source address="2.2.2.2/24"/>
  <service name="mongo"/>
</zone>

查看mongo.xml服务的防火墙生效情况

firewall-cmd --list-all-zones
...
mongo
  interfaces: 
  sources: 2.2.2.2/24 
  services: mongo
  ports: 
  masquerade: no
  forward-ports: 
  icmp-blocks: 
  rich rules:
...

PS:如果一个IP同时应用在多个.xml服务,则只会在最先匹配的服务生效,之后的服务则不匹配该IP。若需要将该IP应用在多个服务,则需要另开服务,将该IP应用的服务都绑定在该服务下。

例如:10.10.86.44同时需要放通ssh、http、mysql等服务

cat multi.xml

<zone>
  <short> multi services</short>
  <description>IP of 10.10.86.44 apply in multi srevices.</description>
  <source address="10.10.86.44"/>
  <service name="ssh"/>
  <service name="mysql"/>
  <service name="http"/>        ##同时添加多个服务
</zone>

firewall-cmd --list-all-zone

multi
  interfaces: 
  sources: 10.10.86.44
  services: http mysql ssh
  ports: 
  masquerade: no
  forward-ports: 
  icmp-blocks: 
  rich rules:

总结:

(1)修改配置文件的方法和命令行添加防火墙策略的方法,都不能立即生效,需要重启或重新加载防火墙配置文件,是新的策略生效。

ervice firewalld restart

firewall-cmd --reload

(2)修改完防火墙后,一定要检查防火墙状态和策略加载状态,若失败则可能拦截所有请求。

(3)以服务(ssh.xml)的方式添加防火墙,可以方便管理。前提需要先查看/usr/lib/firewalld/services中是否定义相应的服务。

(4)若一个IP同时应用多个了服务,则会最先匹配第一个应用了该ip的服务,之后的服务中则不匹配。若需要同时应用到多个服务,则需要另开服务,在该服务(multi.xml)下同时应用多个服务(ssh/http/mysql等)

扩展文档:

1.CentOS7下Firewall防火墙配置用法详解

http://www.centoscn.com/CentOS/Intermediate/2015/0313/4879.html

2.在CentOS7.0 中默认的防火墙 “firewall” 使用方法

http://f.dataguru.cn/thread-473492-1-1.html

3.CentOS 7 巨大变动之 firewalld 取代 iptable

http://blog.csdn.net/smstong/article/details/39317277(外文官方文档)

4.CentOS 7 中firewall-cmd命令

http://blog.sina.com.cn/s/blog_43b39e250102v4zt.html

5.CentOS7 Firewall防火墙配置用法详解

http://www.111cn.net/sys/linux/75503.htm

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