前期准备：反向解析的tree结构是从根往下数，第二级为arpa，第三级为in-addr，第四级为IP，表示出来是：254.58.168.192.in-addr.apra.
1、建立反向解析区域：
[root@centos7 ~]# vim /etc/named.rfc1912.zones
type master;
file "magedu.com.zones";
};
zone "localhost.localdomain" IN {
type master;
file "named.localhost";
allow-update { none; };
};
zone "localhost" IN {
type master;
file "named.localhost";
allow-update { none; };
};
zone "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 {
type master;
file "named.loopback";
allow-update { none; };
};
zone "58.168.192.in-addr.arpa" IN {
type master;
file "named.loopback";
allow-update { none; };
};
"/etc/named.rfc1912.zones" 49L, 1126C
照猫画虎，我们添加了zone "58.168.192.in-addr.arpa" IN {
type master;
file "named.loopback";
allow-update { none; };
}; 内容！
2、[root@centos7 ~]# cd /var/named
[root@centos7 named]# ls
data dynamic magedu.com.zone named.ca named.empty named.localhost named.loopback slaves
[root@centos7 named]# vim 192.168.58.zone
$TTL 86400
@ IN SOA master admin.magedu.com. ( 0 1H 20M 1D 1H )
NS master
master A 192.168.58.254
254 PTR master.magedu.com.
8 PTR www.magedu.com.
9 PTR www.wange.com.
[root@centos7 named]# rndc reload
server reload successful (此处使脚本生效)
以上内容为反向解析脚本内容！
3、测试反向解析结果如下：
[root@Centos6 ~]# dig -x 192.168.58.254
; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.68.rc1.el6 <<>> -x 192.168.58.254 ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 7237 ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0
;; QUESTION SECTION: ;254.58.168.192.in-addr.arpa. IN PTR
;; AUTHORITY SECTION: 58.168.192.in-addr.arpa. 10800 IN SOA 58.168.192.in-addr.arpa. rname.invalid. 0 86400 3600 604800 10800
;; Query time: 7 msec ;; SERVER: 192.168.58.254#53(192.168.58.254) ;; WHEN: Thu Jan 31 21:06:38 2019 ;; MSG SIZE rcvd: 94
[root@Centos6 ~]# dig -x 192.168.58.8
; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.68.rc1.el6 <<>> -x 192.168.58.8 ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 53711 ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0
;; QUESTION SECTION: ;8.58.168.192.in-addr.arpa. IN PTR
;; AUTHORITY SECTION: 58.168.192.in-addr.arpa. 10800 IN SOA 58.168.192.in-addr.arpa. rname.invalid. 0 86400 3600 604800 10800
;; Query time: 6 msec ;; SERVER: 192.168.58.254#53(192.168.58.254) ;; WHEN: Thu Jan 31 21:06:49 2019 ;; MSG SIZE rcvd: 92
[root@Centos6 ~]# dig -x 192.168.58.9
; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.68.rc1.el6 <<>> -x 192.168.58.9 ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 26461 ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0
;; QUESTION SECTION: ;9.58.168.192.in-addr.arpa. IN PTR
;; AUTHORITY SECTION: 58.168.192.in-addr.arpa. 10800 IN SOA 58.168.192.in-addr.arpa. rname.invalid. 0 86400 3600 604800 10800
;; Query time: 1 msec ;; SERVER: 192.168.58.254#53(192.168.58.254) ;; WHEN: Thu Jan 31 21:06:53 2019 ;; MSG SIZE rcvd: 92
以上内容为反向解析的内容！！！
当我们不小心把网址输错了，但是百度，京东，淘宝等网站却还可以访问是为什么？
答：他们在下面添加了 * 无论用户输入什么信息，只要后缀正确，均可以访问。
[root@centos7 named]# vim magedu.com.zone
$TTL 1D
@ IN SOA master admin.magedu.com. (
20190131 ; serial
1D ; refresh
1H ; retry
1W ; expire
3H ) ; minimun
NS master
@ A 192.68.58.130
master A 192.168.58.254
www CNAME websrv
websrv A 192.168.58.133
blog A 192.168.58.136
@ mx 10 mailsrv1
@ mx 20 mailsrv2
mailsrv1 A 192.168.58.137
mailsrv2 A 192.168.58.138
* A 192.168.58.254
[root@Centos6 ~]# ping wwwwwwww.magedu.com
PING www.magedu.com (101.200.188.230) 56(84) bytes of data.
64 bytes from 101.200.188.230: icmp_seq=1 ttl=53 time=5.48 ms
64 bytes from 101.200.188.230: icmp_seq=2 ttl=53 time=6.39 ms
64 bytes from 101.200.188.230: icmp_seq=3 ttl=53 time=6.84 ms
64 bytes from 101.200.188.230: icmp_seq=4 ttl=53 time=5.84 m
这是加 * 的效果，
[root@Centos6 ~]# ping magedu.com
PING magedu.com (101.200.188.230) 56(84) bytes of data.
64 bytes from 101.200.188.230: icmp_seq=1 ttl=53 time=7.01 ms
64 bytes from 101.200.188.230: icmp_seq=2 ttl=53 time=5.59 ms
64 bytes from 101.200.188.230: icmp_seq=3 ttl=53 time=7.43 ms
这是加 @ 的效果。
