DNS拓扑架构图：
1，主域名服务器配置：
~]# yum install bind –y
~]# systemctl start named.service
~]# systemctl enable named.service
查看named进程关端口号
修改配置文件（仅列出有修改配置）
~]# vim /etc/named.conf
options {
listen-on port 53 { 127.0.0.1;172.16.100.67; };
// allow-query { localhost; };
dnssec-enable no;
dnssec-validation no;
检查配置文件语法错误（默认/etc/named.conf）
~]# named-checkconf
重读配置文件
~]# rndc reload
dig命令
查询www.baidu.com A记录
[root@james ~]# dig -t A www.baidu.com
跟踪解析过程
[root@james ~]# dig +trace -t A www.baidu.com
Host命令查询A记录
[root@james ~]# host -t A www.baidu.com
查看NS域名服务器记录
[root@james ~]# host -t NS baidu.com
查询MX邮件服务器记录
[root@james ~]# host -t MX baidu.com
Nslookup命令用法
查询A记录
[root@james ~]# nslookup
> server 172.16.100.67(指定dns解析)
Default server: 172.16.100.67
Address: 172.16.100.67#53
> set q=A（指定查询记录类型）
> www.baidu.com（查询内容）
Server: 172.16.100.67
Address: 172.16.100.67#53
Non-authoritative answer:
www.baidu.com canonical name = www.a.shifen.com.
Name: www.a.shifen.com
Address: 14.215.177.38
Name: www.a.shifen.com
Address: 14.215.177.39
配置解析一个正向区域：
(1) 定义区域
vim /etc/named.rfc1912.zones
zone "iecentury.com" IN {
type master;
file "iecentury.com.zone";
};
注意：区域名字即为域名；
(2) 建立区域数据文件（主要记录为A或AAAA记录，在/var/named目录下建立区域数据文件；）
[root@james ~]# vim /var/named/iecentury.com.zone
$TTL 3600
$ORIGIN iecentury.com.
@ IN SOA ns1.iecentury.com. dnsadmin.iecentury.com. (
201812031
1H
10M
3D
1D )
IN NS ns1
IN MX 10 mx1
IN MX 20 mx2
ns1 IN A 172.16.100.67
mx1 IN A 172.16.100.68
mx2 IN A 172.16.100.69
www IN A 172.16.100.67
web IN CNAME www
权限及属组修改：
# chgrp named /var/named/iecentury.com.zone
# chmod o= /var/named/iecentury.com.zone
检查语法错误
]# named-checkconf
]# named-checkzone iecentury.com /var/named/iecentury.com.zone
(3) 让服务器重载配置文件和区域数据文件
# rndc reload 或
# systemctl reload named.service
[root@james ~]# rndc status
version: 9.9.4-RedHat-9.9.4-61.el7_5.1 <id:8f9657aa>
CPUs found: 8
worker threads: 8
UDP listeners per interface: 8
number of zones: 102 成功+1（默认101）
debug level: 0
xfers running: 0
xfers deferred: 0
soa queries in progress: 0
query logging is OFF
recursive clients: 0/0/1000
tcp clients: 0/100
server is up and running
配置解析一个反向区域
(1) 定义区域 (在主配置文件中或主配置文件辅助配置文件中实现)；
~]# vim /etc/named.rfc1912.zones
zone "100.16.172.in-addr.arpa" IN {
type master;
file "100.16.172.zone";
};
注意：反向区域的名字
反写的网段地址.in-addr.arpa
示例：100.16.172.in-addr.arpa
(2) 定义区域解析库文件（主要记录为PTR）
在/var/named目录下建立区域数据文件；示例：区域名称为100.16.172.in-addr.arpa；（反过来写IP）
[root@james ~]# vim /var/named/100.16.172.zone
$TTL 3600
$ORIGIN 100.16.172.in-addr.arpa.
@ IN SOA ns1.iecentury.com. nsadmin.iecentury.com. (
2014100801
1H
10M
3D
12H )
IN NS ns1.iecentury.com.
67 IN PTR ns1.iecentury.com.
68 IN PTR mx1.iecentury.com.
69 IN PTR mx2.iecentury.com.
67 IN PTR www.iecentury.com.
权限及属组修改：
~]# chmod o= /var/named/100.16.172.zone
~]# chgrp named /var/named/100.16.172.zone
检查语法错误：
~]# named-checkzone 100.16.172.zone /var/named/100.16.172.zone
~]# named-checkconf
~]#rndc reload
[root@james ~]# rndc status
version: 9.9.4-RedHat-9.9.4-61.el7_5.1 <id:8f9657aa>
CPUs found: 8
worker threads: 8
UDP listeners per interface: 8
number of zones: 103 成功+1
debug level: 0
xfers running: 0
xfers deferred: 0
soa queries in progress: 0
query logging is OFF
recursive clients: 0/0/1000
tcp clients: 0/100
server is up and running
测试正向解析及反向解析
~]# dig -t A www.iecentury.com
; <<>> DiG 9.9.4-RedHat-9.9.4-61.el7_5.1 <<>> -t A www.iecentury.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 45698
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 2
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;www.iecentury.com. IN A
;; ANSWER SECTION:
www.iecentury.com. 3600 IN A 172.16.100.67
;; AUTHORITY SECTION:
iecentury.com. 3600 IN NS ns1.iecentury.com.
;; ADDITIONAL SECTION:
ns1.iecentury.com. 3600 IN A 172.16.100.67
;; Query time: 21 msec
;; SERVER: 172.16.100.67#53(172.16.100.67)
;; WHEN: 日 11月 04 00:14:56 CST 2018
;; MSG SIZE rcvd: 96
~]# dig -x 172.16.100.67
; <<>> DiG 9.9.4-RedHat-9.9.4-61.el7_5.1 <<>> -x 172.16.100.67
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 56457
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 1, ADDITIONAL: 2
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;67.100.16.172.in-addr.arpa. IN PTR
;; ANSWER SECTION:
67.100.16.172.in-addr.arpa. 3600 IN PTR ns1.iecentury.com.
67.100.16.172.in-addr.arpa. 3600 IN PTR www.iecentury.com.
;; AUTHORITY SECTION:
100.16.172.in-addr.arpa. 3600 IN NS ns1.iecentury.com.
;; ADDITIONAL SECTION:
ns1.iecentury.com. 3600 IN A 172.16.100.67
;; Query time: 1 msec
;; SERVER: 172.16.100.67#53(172.16.100.67)
;; WHEN: 日 11月 04 00:15:13 CST 2018
;; MSG SIZE rcvd: 134