DNS简介：
DNS，Domain Name System，域名系统，用于Internet上域名和IP地址的相互映射，使得用户不用记忆主机IP地址，仅通过与之对应的域名就可以访问该主机。
关于BIND软件：
/downloads/bind/
下面是本地dns服务器搭建过程，环境-centos6.8，本地IP-192.168.3.60。
1.yum安装bind和bind-utils，后者包含dns查询工具dig。
$ yum install bind bind-utils -y
2.修改配置文件 named.conf
$ vim /etc/named.conf
修改内容如下：
options {//添加监听IP-192.168.3.60listen-on port 53 { 127.0.0.1;192.168.3.60; };};//建立正向解析域（本地域）zone "" IN {type master;file ".zone";};//建立反向解析域（本地域）zone "3.168.192.in-addr.arpa" IN {type master;file "3.168.192.zone";};
检查配置语法正确与否：
$ named-checkconf
3.创建区域文件
正向解析：
使用named.localhost文件的副本，更改属组为named。
$ cp named.localhost .zone$ chgrp named .zone$ vim .zone
.zone 内容如下：
$TTL 1D@ IN SOA @ . (020601 ; serial1D; refresh1H; retry1W; expire3H ) ; minimumNS.MX 5 .nsA 192.168.3.60mail A 192.168.3.61wwwA 192.168.3.62bbsA 192.168.3.63
检查语法正确与否：
$ named-checkzone "" /var/named/.zone
反向解析：
使用named.localhost文件的副本，更改属组为named。
$ cp named.localhost 3.168.192.zone$ chgrp named 3.168.192.zone$ vim 3.168.192.zone
3.168.192.zone 内容如下：
$TTL 1D@ IN SOA @ . (020701; serial1D; refresh1H; retry1W; expire3H ) ; minimumIN NS .60IN PTR .61IN PTR .62IN PTR .63IN PTR .
检查语法正确与否：
$ named-checkzone "3.168.192.in-addr.arpa" /var/named/3.168.192.zone
4.启动named，测试dns解析
$ /etc/init.d/named start
$ dig @192.168.3.60 ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.47.rc1.el6_8.4 <<>> @192.168.3.60 ; (1 server found);; global options: +cmd;; Got answer:;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 16609;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 1;; QUESTION SECTION:;.INA;; ANSWER SECTION:. 86400 INA 192.168.3.62;; AUTHORITY SECTION:. 86400 INNS.;; ADDITIONAL SECTION:. 86400 INA 192.168.3.60;; Query time: 0 msec;; SERVER: 192.168.3.60#53(192.168.3.60);; WHEN: Wed Feb 8 13:28:57 ;; MSG SIZE rcvd: 77
遇到的问题和解决方法
1.修改完区域文件，重启named，出错：
$ /etc/init.d/named restartStopping named: [ OK ]Starting named: Error in named configuration:dns_rdata_fromtext: .zone:10: near '.': not a valid numberzone /IN: loading from master file .zone failed: not a valid numberzone /IN: not loaded due to errors._default//IN: not a valid numberzone 3.168.192.in-addr.arpa/IN: loaded serial 020701zone localhost.localdomain/IN: loaded serial 0zone localhost/IN: loaded serial 0zone 1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa/IN: loaded serial 0zone 1.0.0.127.in-addr.arpa/IN: loaded serial 0zone 0.in-addr.arpa/IN: loaded serial 0[FAILED]
原因是正向解析区域文件中，MX记录缺少优先级，由“MX ”改为“MX 5 ”，不再报错。
2.使用named-checkzone检查区域文件，出错：
dns_rdata_fromtext: /var/named/.zone:3: near '1D': not a valid numberzone /IN: loading from master file /var/named/.zone failed: not a valid numberzone /IN: not loaded due to errors.
解决方法：
在第2行” IN SOA “后、” ( “前，添加” @ “或” . “，正确语句如下：
@ IN SOA @ . (......
@ IN SOA . . (......
参考文章：
/fengyutech/p/4917991.html
/Kelly123/p/4225290.html
/hongweigg/article/details/7189175
