DNS高速缓存

一、高速缓存服务配置

yum install bind -y服务端安装高速缓存服务

[root@www squid-3.3.8]# yum install  bind -y
...

systemctl start named ## 服务端开启高速缓存服务

[root@www squid-3.3.8]# systemctl start named

*注意：开启服务时，若因为加密字符不够，无法正常开启；敲击键盘或移动鼠标即可
/etc/rndc.key ## 正常开启后生成文件

[root@www squid-3.3.8]# ll /etc/rndc.key 
-rw-r-----. 1 root named 77 5月   2 21:44 /etc/rndc.key
[root@www squid-3.3.8]# systemctl status named
named.service - Berkeley Internet Name Domain (DNS)
   Loaded: loaded (/usr/lib/systemd/system/named.service; disabled)
   Active: active (running) since 四 2018-05-03 09:09:02 EDT; 1min 38s ago
  Process: 1963 ExecStart=/usr/sbin/named -u named $OPTIONS (code=exited, status=0/SUCCESS)
  Process: 1962 ExecStartPre=/usr/sbin/named-checkconf -z /etc/named.conf (code=exited, status=0/SUCCESS)
 Main PID: 1966 (named)
   CGroup: /system.slice/named.service
           └─1966 /usr/sbin/named -u named

5月 03 09:09:12 www.westos.com named[1966]: error (network unreachable) resolving './DNSKEY/IN': 2001:500:2f::f#53
5月 03 09:09:12 www.westos.com named[1966]: error (network unreachable) resolving './DNSKEY/IN': 2001:7fd::1#53
5月 03 09:09:12 www.westos.com named[1966]: error (network unreachable) resolving 'dlv.isc.org/DNSKEY/IN': 2001:500:2d::d#53
...

`/etc/resolv.conf` ## 客户端修改DNS配置文件
  ```
  1 # Generated by NetworkManager
  2 search westos.com
  3 nameserver 172.25.254.179                               

nameserver 172.25.254.177 ##dns服务器