DNS主从同步实验

dns域名解析原理

实验步骤1、主dns要完成dns解析：192.168.21.128

[root@localhost ~]#  yum  install bind  -y
[root@localhost ~]# systemctl  start named
[root@localhost ~]# vim /etc/named.conf
options {
        listen-on port 53 { any; };
        directory       "/var/named";
        allow-query     { any; };
allow-transfer  { 192.168.21.129; };   #转发给哪个从dns
}


zone "zhang.com." IN {
        type master;
        file "named.zhang.com";
};

zone "21.168.192.in-addr.arpa" IN {
        type master;
         file "named.192.168.21.zone";
};


[root@localhost ~]# cp  -a  /var/named/named.localhost     /var/named/named.zhang.com

[root@localhost ~]# cp  -a  /var/named/named.localhost     /var/named/named.192.168.21.zone
vim   /var/named/named.zhang.com

vim  /var/named/named.192.168.21.zone

[root@localhost ~]# systemctl  restart named

[root@localhost ~]# systemctl stop firewalld

从：192.168.21.129

[root@localhost ~]#  yum  install bind  -y

[root@localhost ~]# systemctl  start named

[root@localhost ~]# vim /etc/named.conf

options {

        listen-on port 53 { any; };

        directory       "/var/named";

        allow-query     { any; };

}

zone "zhang.com." IN {

   type slave;

        masters { 192.168.21.128; };

        file "slaves/named.zhang.com";

};

zone "21.168.192.in-addr.arpa" IN {

        type slave;

        masters { 192.168.21.128; };

        file "slaves/named.192.168.21.zone";

};

[root@localhost ~]# systemctl  restart named
[root@localhost ~]# systemctl stop firewalld

测试：

注意：在安装软件前记得先挂载；

在配置文件时注意配置要求以及格式，如配置域名是xixi.com.后的"."如果缺少就可能导致报错；在named.zhang.com文件的配置时，注意区别A与PTR的区别及应用；注意防火墙有没有关闭等。