RHCA 完成 DNS 配置

1. 安装 dns 软件 bind

   yum install bind
   

2. 配置文件
   • 主配置文件 /etc/named.conf
   • zone 配置文件目录 /var/named/
   • 修改主配置文件

   vim /etc/named.conf
   options{
   	listen-on port 53 { any; };
   	...
   	allow-query { localhost; 172.25.250.0/24; };
   }
   

3. 添加zone 区域文件，添加正向解析
   vim /var/named/lab.example.com.zone

$TTL 1D
@         IN  SOA  servera.lab.example.com.  rname.invalid. (
0 1D 1H 1W 3H )
          IN NS servera
servera   IN A   172.25.250.10
serverb   IN A   172.25.250.11

4. 添加 zone 区域文件，添加反向解析
   vim /var/named/25.172.loopback.zone

$TTL 1D
@         IN  SOA  servera.lab.example.com.  rname.invalid. (
0 1D 1H 1W 3H )
               NS servera.lab.example.com.
10.250    PTR  servera.example.com.
11.250    PTR  serverb.example.com.

5. 使用 named-checkzone 检查配置文件

   named-checkzone example.com /var/named/lab.example.com.zone
   named-checkzone 172.25.250.11 /var/named/25.172.loopback.zone
   

6. 将 zone 区域关联到主配置文件，写在后面

zone "lab.example.com" IN {
       type master;
       file "lab.example.com.zone";
};

zone "25.172.in-addr.arpa" IN {
	   type master;
	   file "25.172.loopback.zone";
};

7. 添加文件权限

[root@host ~]# chmod 640 /var/named/*.zone
[root@host ~]# chcon -t named_zone_t /var/named/*.zone
[root@host ~]# chown root:named /var/named/*.zone

8. 检查配置文件是否OK

named-checkconf -z /etc/named.conf

9. 重启服务并设置开机启动

systemctl enable named
systemctl restart named

10. 错误时查看日志

systemctl status named
journalctl -xe

11. 设置防火墙开启 DNS

firewall-cmd --permanent --add-service=dns
firewall-cmd --reload
firewall-cmd --list-all # 检查是否有 dns

12. 验证DNS 是否配置成功

host servera.lab.example.com 172.25.250.10
host serverb.lab.example.com 172.25.250.10
host 172.25.250.10 172.25.250.10
host 172.25.250.11 172.25.250.10

13. 在其他服务器上，执行 10 11 步
14. 示例文件

# zone 示例文件
/var/named/named.locahost
/var/named/named.loopback
# 在主文件中配置 zone
/usr/share/doc/bind/sample/etc/named/rfc.1912.zones
# 查找示例文件
find /usr -name "*zones*"