整体架构的构架图如下图（其中服务器用centos8系统搭建，测试客户端用centos7系统实现）
1.8台主机介绍
DNS客户端：10.0.0.7/24
本地DNS服务器（只缓存）：10.0.0.8/24
转发目标DNS服务器：10.0.0.18/24
根DNS服务器：10.0.0.28/24
org域DNS服务器：10.0.0.38/24
magedu.org域主DNS服务器：10.0.0.48/24
magedu.org域从DNS服务器：10.0.0.58/24
www.magedu.org的WEB服务器：10.0.0.68/24
2.服务器具体的搭建过程
#为防止服务器搭建过程出现错误，我们从后往前搭建（利用测试客户端不断检测，以免搭建过程出现错误）
（1）搭建web服务器10.0.0.68
[root@centos68 ~]$yum -y install httpd
[root@centos68 ~]$systemctl enable --now httpd
Created symlink /etc/systemd/system/multi-user.target.wants/httpd.service →/usr/lib/systemd/system/httpd.service.
[root@centos8 ~]$echo www.magedu.org > /var/www/html/index.html
（2）搭建主DNS服务器：10.0.0.48
[root@centos48 ~]$yum -y install bind bind-utils
[root@centos48 ~]$vim /etc/named.conf
// listen-on port 53 { 127.0.0.1; };
// allow-query { localhost; };
[root@centos48 ~]$vim /etc/named.rfc1912.zones
zone "magedu.org" {
type master;
file "magedu.org.zone";
};
[root@centos48 ~]$vim /var/named/magedu.org.zone
1 $TTL 1D
2 @ IN SOA master admin.magedu.org. (
3 1 ; serial
4 1D ; refresh
5 1H ; retry
6 1W ; expire
7 3H ) ; minimum
8 NS master
9 NS slave
10 master A 10.0.0.48
11 slave A 10.0.0.58
12 www A 10.0.0.68
[root@centos48 ~]$systemctl start named
（3）搭建从DNS服务器：10.0.0.58
[root@centos58 ~]$yum -y install bind bind-utils
[root@centos58 ~]$vim /etc/named.conf
// listen-on port 53 { 127.0.0.1; };
// allow-query { localhost; };
[root@centos58 ~]$vim /etc/named.rfc1912.zones
zone "magedu.org" {
type slave;
masters {10.0.0.48;};
file "slaves/magedu.org.zone";
};
[root@centos58 ~]$systemctl start named
[root@centos58 ~]$ll /var/named/slaves/
total 4
-rw-r--r-- 1 named named 319 May 31 14:53 magedu.org.zone
（4）搭建org域DNS服务器：10.0.0.38
[root@centos38 ~]$yum -y install bind bind-utils
[root@centos38 ~]$vim /etc/named.conf
// listen-on port 53 { 127.0.0.1; };
// allow-query { localhost; };
[root@centos38 ~]$vim /etc/named.rfc1912.zones
zone "org" IN {
type master;
file "org.zone";
};
[root@centos38 ~]$vim /var/named/org.zone
$TTL 1D
@ IN SOA master admin.magedu.org. ( 1 1D 1H 1W 3D )
NS master
magedu NS mageduns1
magedu NS mageduns2
master A 10.0.0.38
mageduns1 A 10.0.0.48
mageduns2 A 10.0.0.58
[root@centos38 ~]$systemctl restart named
（5）搭建根DNS服务器：10.0.0.28
[root@centos28 ~]$yum -y install bind bind-utils
[root@centos28 ~]$vim /etc/named.conf
// listen-on port 53 { 127.0.0.1; };
// allow-query { localhost; };
#默认有根服务器，所有更改在53行
zone "." IN {
type master;
file "root.zone";
};
[root@centos28 ~]$vim /var/named/root.zone
$TTL 1D
@ IN SOA master admin.magedu.org. ( 1 1D 1H 1W 3D )
NS master
org NS orgns
master A 10.0.0.28
orgns A 10.0.0.38
[root@centos28 ~]$systemctl start named
（6）搭建转发目标DNS服务器：10.0.0.18
[root@centos18 ~]$yum -y install bind bind-utils
[root@centos18 ~]$vim /etc/named.conf
// listen-on port 53 { 127.0.0.1; };
// allow-query { localhost; };
33 dnssec-enable no;
34 dnssec-validation no;
[root@centos18 ~]$vim /var/named/named.ca
. 518400 IN NS a.root-servers.net.
a.root-servers.net. 518400 IN A 10.0.0.28
[root@centos18 ~]$systemctl restart named
（7）搭建本地DNS服务器（只缓存）：10.0.0.8
[root@centos 8 ~]$yum -y install bind bind-utils
[root@centos 8 ~]$vim /etc/named.conf
// listen-on port 53 { 127.0.0.1; };
// allow-query { localhost; };
forward only;
forwarders {10.0.0.18;};
33 dnssec-enable no;
34 dnssec-validation no;
[root@centos8 ~]$systemctl restart named
（8）客户端10.0.0.7测试部分（此部分并非为最后一步，而是随着七台服务器的搭建过程中随时测试，出现以下测试结果则服务器搭建成功）
[root@centos7 ~]$curl 10.0.0.68
www.magedu.org
[root@centos7 ~]$host www.magedu.org 10.0.0.48
Using domain server:
Name: 10.0.0.48
Address: 10.0.0.48#53
Aliases:
www.magedu.org has address 10.0.0.68
[root@centos7 ~]$host www.magedu.org 10.0.0.58
Using domain server:
Name: 10.0.0.58
Address: 10.0.0.58#53
Aliases:
www.magedu.org has address 10.0.0.68
[root@centos7 ~]$host www.magedu.org 10.0.0.38
Using domain server:
Name: 10.0.0.38
Address: 10.0.0.38#53
Aliases:
www.magedu.org has address 10.0.0.68
[root@centos7 ~]$host www.magedu.org 10.0.0.28
Using domain server:
Name: 10.0.0.28
Address: 10.0.0.28#53
Aliases:
www.magedu.org has address 10.0.0.68
[root@centos7 ~]$host www.magedu.org 10.0.0.18
Using domain server:
Name: 10.0.0.18
Address: 10.0.0.18#53
Aliases:
www.magedu.org has address 10.0.0.68
[root@centos7 ~]$host www.magedu.org 10.0.0.8
Using domain server:
Name: 10.0.0.8
Address: 10.0.0.8#53
Aliases:
www.magedu.org has address 10.0.0.68
[root@centos7 ~]$curl www.magedu.org
www.magedu.org
[root@centos7 ~]$